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BACK 1 2 3 4 5 6 7 NEXT NO. Title Presented at & Date Author Project Team / Research Division Abstract 11625 International Joint Study on CO2-EOR - Study on Applicability of CO2-EOR to Rang Dong Field, offshore Vietnam - International Energy Agency Collaborative Project on Enhanced Oil Recovery 2009/9/21-23 Sunao Takagi, Hiroshi Mitsuishi, Komei Okatsu, Hiroshi Okabe, Yohei Kawahara (Japan Oil, Gas and Metals National Corporation), NguyenVan Toan (Petrovietnam), Phan Ngoc Trung (Vietnam Petroleum Institute), Yoshiaki Ueda, Tadao Uchiyama (Nippon Oil Exploration Limited) EOR Research Division ［Abstract］"CO2 EOR application to the oil field in Vietnam offshore is being investigated through an international joint study between Japan and Vietnam not only for gas EOR process application but for CO2 emission reduction purpose. Even though there is not much technical difference between onshore and offshore fields on CO2 EOR, the major difference is the distance from the CO2 source, additional cost for CO2 injection/treatment facility and less dense well coverage in general, which make the project challenging. Target reservoir is the Lower Miocene sandstone reservoir and is located 120 km offshore of southern Vietnam. The reservoir is thin-layered sandstone reservoir with the depth of 2,100 mss and 50m gross thickness. This paper addresses the aspects of CO2 miscibility test, core flood test, reservoir simulation and CO2 capture/transportation study. Once this project is realized, this will be the first offshore CO2 EOR application in Southeast Asia." 11622 Visualisation of supercritical CO2 distributions in porous media SPE forum “CO2 Capture and Storage: Can the Oil & Gas Industry Support its Development and Deployment?” 2009/9/13-18 Hiroshi Okabe, Yoshihiro Tsuchiya (Japan Oil, Gas and Metals National Corporation), C. H. Pentland, S. Iglauer, M. J. Blunt (Imperial College London) EOR Research Division ［Abstract］Visualisation of supercritical CO2 distributions in porous media 11619 Verification of Microbial Activities for Microbial Restoration of Methane Deposit with Subsurface CO2 Sequestration into Depleted Oil Fields Society of Petroleum Engineers 2009/8/4-9 Hiroshi Otagaki, Kazuhiro Fujiwara, Yoshiyuki Hattori (Chugai Techanos Corporation), Yuichi Sugai (Kyushu University), Komei Okatsu (Japan Oil, Gas and Metals National Corporation) R&D Team for CCS and Environmental Management ［Abstract］The objective of this research is to estimate the possibility of microbial restoration of methane deposits using subsurface sequestered CO2 and indigenous anaerobes in depleted oil fields. The most important factors are the efficiency and velocity of methane conversion by indigenous anaerobes inhabiting a reservoir. Field samples (producing oil and water) from oil field in Japan were collected and analyzed in order to clarify the existence and survivability of indigenous methane-producing anaerobes under reservoir conditions. The hydrogenotrophic methanogen consortium MYH-4 consortium was separated from the enrichment culture added oil reservoir water. By using MYH-4 consortium, two experiments were conducted. (�@) Direct calculation of the CO2 to methane conversion rate for economic assessment. (�A) As the main objective of the field operation test, it is necessary to identify the state of the subsurface injection environment and the limitations that it poses to methane production. To clarify this, the experiment was carried out by using stable isotope probing. At the result of these studies, it has been understood that the methane conversion efficiency from CO2 was approximately 50%. 11618 Reservoir characterization of the methane hydrate bearing turbidite channel in the Eastern Nankai Trough, Japan AOGS (Asia Oceania Geosciences Society) 2009/8/14 Satoshi Noguchi, Naoyuki Shimoda, Tatsuo Saeki, Takao Inamori, Toshiaki Kobayashi, Tetsuya Fujii (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Reservoir characterization of the methane hydrate bearing turbidite channel in the Eastern Nankai Trough, Japan 11617 Experimental study of underwater rock drilling using a pulsed Ho:YAG laser-induced jets Shock Waves（An International Journal on Shock Waves, Detonation and Explosions） 2009/8/3 Kiyonobu Ohtani, Daiki Numata, Kazuyoshi Takayama (Tohoku University), Toshio Kobayashi (Japan Drilling Co., Ltd.), Komei Okatsu (Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］This paper is primarily an assessment of laser-induced water jets for boring rock surfaces. It also reports the result of preliminary experiments of pulsed Ho:YAG laser-induced jets applied to drill a submerged rock specimen. The irradiation of pulsed Ho:YAG laser beams at 3 Hz inside a thin metal tube produces intermittent water vapor bubbles which result in liquid jet discharge from the exit of the metal tube. The laser-induced water jets are visualized by shadowgraphs and images are recorded by a high-speed digital video camera. High stagnation pressures were eventually generated by the jet impingements. Simultaneously shock waves of about 22.7 MPa were generated at bubble collapse, which effectively cracked the surface of the rock specimens. Repeated exposures of these laser-induced jets against submerged rock specimens have a potential to practically bore holes on rock surfaces. 11616 Investigations of Sediment Effect on Gas Hydrate Formation in Natural Sediment AOGS (Asia Oceania Geosciences Society) 2009/8/13 Toshiyasu Ukita (Japan Oil, Gas and Metals National Corporation), Hailong Lu (National Research Council Canada), Satoshi Noguchi, Tatsuji Kawasaki, Tadaaki Shimada (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］The accurate estimate of the resource of natural gas hydrate is one of the most important issues in assessing the energy potential of natural gas hydrate, which relies largely on the data precision of hydrate saturation level in the sediments of a reservoir. Occurring in sediment pore has been recognized as the primary occurrence mode of gas hydrate in the Eastern Nankai trough area. It was suggested that the distribution of coarsegrained sands is one of the most important factors controlling the occurrence of natural gas hydrates. This research aimed at elucidating the particle size and clay mineral effects on hydrate saturation in sediments through an experiment approach. The specimens, including sand, silty sand, silt, representing of the main sediment types recovered from the gas hydrate distribution region of the Eastern Nankai Trough, were tested. The obtained results from the experiments clearly indicate a particle size and clay content dependent trend, being low in saturation in fine sediment but high in coarse sediment. These results are generally consistent with NMR logging results for high-saturation samples, but somewhat different for samples with medium or low saturation levels. For a better understanding of the mechanism of these two factors, studies have been carried out to investigate the saturation level of methane hydrate in a series of silica powders and clay. The results obtained indicate that particle size and clay contents are the two key factors determining the saturation level of gas hydrate in sediments: the finer the particle size and/or the higher the clay content, the lower the hydrate saturation. It has been found that fundamentally the effect of particle size or clay mineral on hydrate saturation level can be accredited to specific surface area of sediment. This study was carried out as a part of the research undertaken by The Research Consortium for Methane Hydrate Resources in Japan (MH21) 11615 Evaluation of concentrated zone α as reservoir AOGS (Asia Oceania Geosciences Society) 2009/8/13 Toshiaki Kobayashi, Tatsuo Saeki, Takao Inamori, Satoshi Noguchi (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Evaluation of concentrated zone α as reservoir 11614 Seismic Interpretation and Analysis for Methane Hydrate Reservoir: Strategy and Applications AOGS (Asia Oceania Geosciences Society) 2009/8/12 Tatsuo Saeki, Takao Inamori, Toshiaki Kobayashi, Masao Hayashi, Satoshi Noguchi, Naoyuki Shimoda (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Seismic Interpretation and Analysis for Methane Hydrate Reservoir: Strategy and Applications 11602 Overburden Heterogeneity Effects in Migration Velocity Analysis – A Case Study in an Offshore Australian Field European Association of Geosciences and Engineering (EAGE) 2009 2009/6/11 Mamoru Takanashi (Japan Oil, Gas and Metals National Corporation), Masamichi Fujimoto (INPEX Browse, Ltd), Dimitri Chagalov (CGGVeritas) Oil & Gas Upstream Technology Unit ［Abstract］Seismic velocity has been used for reducing uncertainty of time-to-depth conversion. In the offshore Australian study field, there is a problem in the RMS velocity provided by Kirchhoff PSTM. The velocity pattern dominates NE-SW directed undulated patterns, which do not match with the geological trend. We investigated the origin of undulation by forward modeling and seismic data review. We found that the narrow, elongated velocity anomalies in the shallow Tertiary sequence cause the PSTM velocity distortions along the target. The magnitude of the distortion in the deeper area can be stronger in Kirchhoff PSDM velocity analysis, if the velocity model does not represent true shallow velocity anomalies. The application of PSDM using a precise overburden velocity model necessitated the removal of distortion and a correct representation of the target reservoir structure. 11600 Screening Study of Chemical EOR Flooding in the Chicontepec Field The Mexican Petroleum Congress, Veracruz 2009 2009/6/10-14 M. Abbaszadeh (IPS), Komei Okatsu (Japan Oil, Gas and Metals National Corporation), A. Farhadinia, M. Delshad, G.A. Pope (U. of Texas at Austin) EOR Research Division ［Abstract］"This paper presents a screening study for the application of chemical EOR methods of polymer, surfactant polymer (SP) and alkaline surfactant polymer (ASP) in Chicontepec fields through mechanistically-based simulations using the UTCHEM simulator. A finely-characterized 20 acre five-spot sector model within the lower sands of the Agua Fria field is considered, and numerous chemical flooding sensitivity simulations are conducted based on laboratory data available for similar crude oil and formation properties of Chicontepec oil field. Design parameters such as surfactant and polymer concentrations, surfactant slug size, polymer drive size and concentration, salinity of the polymer drive, polymer and surfactant adsorptions are the sensitivity parameters. Injectivity of these chemical EOR agents is also investigated to assess the operational and economic viability of such EOR projects. The simulations show average incremental oil recovery factor (over waterflood) of about 5%, 18% and 24% OOIP for polymer, SP and ASP; respectively. These incremental recovery figures are slightly lower than the expected results in other fields in the world with moderate reservoir permeability ranges, but still quite attractive for the low permeability Chicontepec field, given the typical performance and consumption of the chemicals. Thus, attractive incremental oil recoveries are possible and hence there is potential for chemical EOR in Chiontepec. " 11599 Uncertainty Assessment of Oil Recovery by CO2-EOR Processes in Chicontepec The Mexican Petroleum Congress, Veracruz 2009 2009/6/10-14 M. Abbaszadeh (IPS), Hirofumi Okano, Kenji Ohno (Japan Oil, Gas and Metals National Corporation) EOR Research Division ［Abstract］This paper presents an investigation of ranges of uncertainty in the oil recovery by water, CO2 and CO2-WAG injections into an inverted 7-spot pilot simulation model in a lower sand body of the Tajin field of Chicontepec. First, 50 integrated geostatistical reservoir characterization realizations are ranked based on a pay-sand connectivity between all well pairs in the sector model. The criterion for the connectivity is discussed. Second, 10 geostatistical realizations, covering worst to best connectivity (i.e., reservoir rock quality ranging from poor to good) are selected for flow simulations and assessment of oil recovery factor for uncertainty evaluation. Each of the selected models is upscaled for compositional flow simulations and calibrated to dynamic production data. Water, CO2 and CO2-WAG are injected into the 10 calibrated models for 15 years, and ranges of uncertainty in recovery factors are subsequently captured. The results show that CO2-EOR processes recover 7-10% additional oil compared to waterfloods for the same reservoir characteristics. Consistently higher incremental recovery factors by CO2-EOR for varied reservoir heterogeneity signify the economic value of CO2 injection for field development. 11581 Methane Hydrate R&D Activities in JOGMEC - Overview and Status - 3rd International R&D Forum on Oil, Gas & Petrochemicals 2009/5/26 Kenichi Yokoi (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］"Methane hydrate is expected to be future domestic energy which contributes to Japan’s energy security. Japan’s Methane Hydrate R&D Program started under the Ministry of Economy, Trade and Industry in July 2001, which intended to promote technical development for possible production of methane gas from hydrate. The program has been extended over 18 years (until 2018) and divided into three phases. To implement the program, “MH21 Research Consortium” was established. As a member of MH21 Research Consortium, JOGMEC is responsible for research group for resource assessment and had primary been conducting (1) assessment of methane hydrate resources in the Nankai Trough area, offshore Japan, and (2) onshore production test in Canada, during phase 1 (2001 to 2008) based on the program. In the eastern Nankai Trough area, the occurrence of methane hydrate filling pore space of sand layers was revealed through the drilling of the METI exploratory wells in 1999 and 2004. Thick methane hydrate concentrated zones composed of highly hydrate saturated turbidites sand were also confirmed. Resource assessment of methane hydrate in the eastern Nankai Trough area was conducted through probabilistic approach using 2D/3D seismic and well data." 11578 Quartz cementation and reservoir quality of the Plover sandstone in the Abadi Gas Field Indonesian Petroleum Association, the 33rd Annual Convention & Exhibition 2009/5/6 Ryoichi Matsui, Emiko Shinbo, Mamoru Omokawa (Japan Oil, Gas and Metals National Corporation), Takahiro Zushi (INPEX Masela, Ltd.) Geology & Geophysics Research Division ［Abstract］"Quartz cementation is the most notable diagenetic signature in the Plover reservoir sandstone of the Abadi gas field. It occurs mostly as an overgrowth on the surfaces of detrital quartz grains to a variable degree over the field, and is suspected as a major cause for porosity and permeability reduction of the reservoir. An integrated image analysis was applied to the reservoir sandstones by utilizing cathodoluminescence microscopy, which allowed the volume of quartz cement as well as the depositional texture to be determined in a highly quantitative manner. The analysis has revealed that the amount of quartz cement has negative correlation with the mean grain size for the quartzose sandstones, indicating strong dependence on the depositional texture. The impact of the quartz cementation is interpreted to be quite significant especially on the permeability reduction probably because finer-grained texture provides not only initially-narrower pore throat size, but also more intensive quartz cements in the pore spaces. Structural restoration was also carried out, together with the regional petroleum system analysis, aiming to unravel the burial and the hydrocarbon filling history of the structure. The results indicate that prior to the formation of the current Abadi structure, the northern part of the field area was situated at a relatively shallower depth than the southern part for most of the Tertiary period, implying predominance of lower formation temperatures in the northern part. Because of this, possibly together with the earlier entrapment of the gaseous hydrocarbons in the northern part, the quartz cementation was retarded more effectively in the northern part than in the southern part of the field. The burial and thermal effect on the quartz cementation was also examined from the forward modeling approach, which also suggests that the northern part was at the relatively preferable condition for preservation of the reservoir quality. In summary, the present reservoir quality is concluded to be strongly constrained by the amount of quartz cement originated from the burial and thermal history as well as from the initial depositional texture. Although each of these factors affects the quartz cementation quite differently in areal and vertical scales from the other, both are considered to be of equal importance as controls on the reservoir quality." 11573 Drilling an F 2 inch Diameter Hole in Granites Submerged in Water by CO2 Lasers SPE/IADC Drilling Conference and Exhibition 2009/3/19 Toshio Kobayashi, Masahiro Nakamura (Japan Drilling Co., Ltd.), Satoshi Kubo, Makoto Ichikawa (Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］Drilling an F 2 inch Diameter Hole in Granites Submerged in Water by CO2 Lasers 11568 Corrosion experience of 13%Cr steel tubing and laboratory evaluation of Super 13Cr steel in sweet environments containing acetic acid and trace amounts of H2S NACE International "Corrosion 2009 Conference & Expo" 2009/3/24 Toshiyuki Sunaba, Yasuyoshi Tomoe, Hiroshi Honda (Inpex Corporation), Tomoko Watanabe (Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］Corrosion experience of 13%Cr steel tubing and laboratory evaluation of Super 13Cr steel in sweet environments containing acetic acid and trace amounts of H2S 11571 GAS TO WIRE SYSTEM (GTW): A Most Effective Concept for Using Associated Gas Utilising Associated Gas 2009/2/26 Tomoko Watanabe (Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］GAS TO WIRE SYSTEM (GTW): A Most Effective Concept for Using Associated Gas 11569 Development of Natural Gas Hydrate Supply Chain Qatar-Japan Joint Seminar on Technical and Economic Energy Issues 2009/2/15-16 Satoo Nakai (Mitsui Engineering and Shipbuilding Co., Ltd.) Research Project Team on Emerging Gas Technologies ［Abstract］Development of Natural Gas Hydrate Supply Chain 11564 Improved History Matching of Waterflood and Tracer Data, Mexico 29th Annual Workshop & symposium Collaborative Project on Enhanced Oil Recovery　International Energy Agency 2008/11/5 Mizuki Watanabe (Japan Oil, Gas and Metals National Corporation) EOR Research Division ［Abstract］A series of sensitivity studies are conducted using a waterflood pilot sector model, and 2D models. The aim is to improve the history matching of an upscaled model to available waterflood and tracer data. The subject reservoir is consisted of alternating sandstone and shale bodies in a Paleogene turbiditic depositional environment. History matching in this reservoir is difficult as the distribution of sand is highly discontinuous. The coarse model is constructed by upscaling an integrated geostatistical fine model in the vertical direction. The reliability of this model is unsatisfactory as the current match to water and tracer data is unacceptable. Sensitivity studies have focussed on anisotropic flow and vertical resolution of the model. Anisotropic flow was analysed using the coarse model. Effects of the vertical resolution were assessed based on 2D models of different vertical resolutions. 11561 Concept of Methane Hydrate System in the eastern Nankai Trough 2008 AGU Fall Meeting 2008/12/18 Sadao Nagakubo, Tetsuya Fujii, Satoshi Noguchi, Tatsuji Kawasaki (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］By the study of the Phase 1 (FY2001-2008) of the Research Consortium for Methane Hydrate Resources in Japan (MH21 Research Consortium), MH21 Research Consortium showed that methane hydrates pore-filled in sandy sediments had a potential to develop in the future. It is important to clarify the accumulation mechanism and processes of methane hydrates pore-filled in sandy sediment because it would contribute to explore new methane hydrate filed to develop other than the eastern Nankai Trough in the future. Therefore Japan Oil, Gas and Metals National Corporation (JOGMEC), as a member of MH21 Research Consortium, has been constructing a concept of Methane Hydrate System (methane generation and migration, MH formation and dissociation) with methane hydrates pore-filled in sandy sediment. We extracted critical elements and executed processes to summarize Methane Hydrate System in the eastern Nankai Trough by reviewing past geochemical analysis, well logs and core analyses, seismic interpretations, and laboratory studies for the eastern Nnkai Trough. We also conducted case studies using 1D and 2D numerical simulators developed for the clarification of methane hydrate accumulation mechanism. It was determined that there are still many unsolved issues as listed below though we try to construct a concept of Methane Hydrate System in the eastern Nankai Trough. 1. Methane source and migrating -methane -dominant generation depth -methane generation rate. -driving forces of methane migration 2. Occurances and distribution -occurrences and distribution of methane hydrates other than methane hydrates pore-filled in sandy sediment. -methane-bearing fluid condition (properties, distribution) below methane hydrate bearing zones. 3. Relation between seafloor phenomena and methane hydrate occurrences. 4. Impact of geohistory and sea level (water depth) change to methane hydrate accumulation. New investigation surveys (drilling and geological/geochemical surveys on seafloor) are required to solve the above issues. 11560 Reservoir characterization of channel-type methane hydrate bearing turbidite sand layer in the eastern Nankai Trough, Japan 2008 AGU Fall Meeting 2008/12/18 Satoshi Noguchi, Naoyuki Shimoda, Tatsuo Saeki, Takao Inamori, Toshiaki Kobayashi, Tetsuya Fujii (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Development process and internal architecture of turbidite channel were discussed using high-resolution 3D seismic data in order to elucidate a potential reservoir characterization of methane hydrate. Recently conducted researches of 2D/3D seismic surveys and multi-wells drilling acquired by METI revealed that methane hydrate found in the eastern Nankai Trough area is distributed in the pore space of turbidite sand base of the stability zone of methane hydrate, namely bottom simulating reflector (BSR) (e.g., Fujii et al., in press; Saeki et al. 2008). Further, the turbidite sand layers in the Tokai-Kumano forearc basins along the Nankai Trough could be roughly classified into channel to lobe system and channel-levee system according to the seismic/sequence stratigraphic analysis (Takano et al., 2008). Our focus on this study is to examine the characteristics of the channel-levee system of methane hydrate bearing turbidite sand layer using seismic geomorphological analysis. In 3D seismic cube, high amplitude reflectors in the turbidite channel above BSR exhibit complex reflection patterns comprising patchy like shape of positive and negative reflectors. Typical high amplitude reflectors represent high acoustic impedance contrast which probably corresponds to the boundary of methane hydrate bearing sand dominated layer. Multi-wells logging also confirmed that the methane hydrate bearing sand layer above BSR forming the methane hydrate (MH) concentrated zone has high density with high resistivity compared with those of without methane hydrate bearing sand and mud layers. The high amplitude reflectors in MH concentrated zone are variable even over short distance along the channel length; this implies that the concentrated zone of methane hydrate bearing turbidite sand is rather complex depending on the well locations. The group of high amplitude reflectors by picking also enables us to display the internal architecture of turbidite channel using 3D visualization technique. Flow direction of main channel shifts from northeast to southwest. However, the contour map of amplitude patterns represents that there is no significant correlation between high amplitude reflectors and main flow direction. This fact may suggest that the turbidite channel consists of complex stacking patterns of several flow units which form the heterogeneous reservoirs of methane hydrate. This work is conducted as the research of Research Consortium for Methane Hydrate Resources in Japan (MH21). 11559 Detailed analysis of methane hydrate concentrated zone of lobe type in eastern Nankai Trough 2008 AGU Fall Meeting 2008/12/18 Toshiaki Kobayashi, Tatsuo Saeki, Takao Inamori, Tetsuya Fujii, Satoshi Noguchi (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］JOGMEC, a member of MH21 Research Consortium, takes charge of a study of the Research for Resources Assessment, and is pursuing a possibility that methane hydrate presumed to be distributed around ocean area of Japan will be energy resources. JOGMEC is currently conducting analysis of 3D seismic data acquired in the eastern Nankai Trough by Ministry of Economy, Trade and Industry in 2002 under the national program of assessment for methane hydrates. Methane hydrate concentrated zones was targeted for offshore production test. Previous research has revealed that methane hydrate concentrated zones were formed in turbidite sand layers and can be classified into lobe type and channel type. The concentrated zones of a lobe type and a channel type which were prospective as resources field were selected as candidate fields in the eastern Nankai Trough. It was necessary to grasp the heterogeneous distribution of methane hydrates for the selection of test sites and target layers, and the determination of specifications of the test. On this study, analysis of detailed internal structure of methane hydrate concentrated zone of lobe type including a well, and geological structure around this zone were conducted. In the results of the detailed analysis, methane hydrate concentrated zone was constructed by many reflectors and it was appeared that amplitude variation of reflector and concentration of methane hydrates in the sand layer were related mutually. The existence of many normal faults extending to east and west were revealed.　It was interpreted that the faults controlled the distribution of methane hydrate bearing sand layers and cut them in the shape of block. Based on the results of this study, the selection of test sites for offshore production and the specifications for the test will be investigated. 11558 Geophysical Surveys over Methane Hydrate Bearing zone in the Nankai Trough, offshore JAPAN 2008 AGU Fall Meeting 2008/12/18 Eiichi Asakawa, Shigeharu Mizohata (JGI, Inc.), Takao Inamori, Tatsuo Saeki, Toshiaki Kobayashi, Kazunobu Yamane (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Various types of geophysical surveys other than conventional 2D and 3D marine seismic have been carried out for the purposes of estimating the distribution and characteristics of methane hydrate. They are a 2D deep-towed seismic survey, OBS surveys and a 2D multi-component survey with ocean bottom cable (RSCS). In this paper, we summarize these surveys and results. A 2D deep-towed seismic survey was carried out in 1996 and the data is processed in 1998 and 2002. Both the source and the hydrophone cable are towed close to the seabed to obtain higher resolution section and velocity profiles compared with 3D marine seismic in the very shallow part. But, we can not recognize BSR clearly on the section and little seismic reflection event can be seen below BSR because of its insufficient source energy. In 1996 and 1997, 4-component ocean bottom seismometer (OBS) data were acquired. We analyzed these data in combination with marine seismic data (MCS). We applied an imaging technique to the OBS reflection data and obtained results that have good agreement with the MCS section. We also applied modeling and inversion procedures to reveal the detailed velocity structure. Travel-time inversion gives elevated P-wave velocities, reaching values of up 2100m/s, above BSR. The S-wave velocities were subsequently derived by event correlation, time picking and forward modeling of the wide-angle data, and they are up to 700-750m/s in the hydrate zone. A 2D multi-component seismic survey was carried out using the RSCS (Real-time Seismic Cable System) system in 2006. The RSCS is an ocean bottom cable system employing a series of 3 component geophones connected with submarine optical cable. The quality of the field data is excellent with high vector fidelity. The vertical component data was imaged using P-wave OBS pre-stack time migration, including Vp migration velocity analysis. The resulting sections showed excellent agreement with the 3D survey migrated date volume. The in-line horizontal component data was imaged using C-wave (PS converted wave) OBS pre-stack time migration, including Vc migration velocity analysis and updates to the gamma ratios. The resulting C-wave sections showed amplitude anomalies above the BSR level. This fact indicates S-wave velocity anomaly and gives useful information to estimate the rock physics model of the methane hydrates. 11557 Oil sands characteristics and time-lapse and P-SV seismic steam monitoring, Athabasca, Canada 2008 AGU Fall Meeting 2008/12/15-19 Akihisa Takahashi, Toru Nakayama, Koji Kahihara (Japan Petroleum Exploration Co., Ltd.), Leigh Skinner (Japan Canada Oil Sands Limited), Ayato Kato (Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Division ［Abstract］Oil sands characteristics and time-lapse and P-SV seismic steam monitoring, Athabasca, Canada 11556 The Saturation Level of Methane Hydrate in Natural Sediments 2008 AGU Fall Meeting 2008/12/15-19 Tatsuji Kawasaki (Japan Oil, Gas and Metals National Corporation), Hailong Lu (National Research Council Canada), Tetsuya Fujii (Japan Oil, Gas and Metals National Corporation), John A. Ripmeester (National Research Council Canada) Research Project Team on Emerging Gas Technologies ［Abstract］The accurate estimate of the resource of natural gas hydrate is one of the most important issues in assessing the energy potential of natural gas hydrate, which relies largely on the data precision of hydrate saturation level in the sediments of a reservoir. Occurring in sediment pore has been recognized as the primary occurrence mode of gas hydrate in the Eastern Nankai trough area. It was suggested that the distribution of coarse-grained sands is one of the most important factors controlling the occurrence of natural gas hydrates. This research aimed at elucidating the particle size and clay mineral effects on hydrate saturation in sediments through an experiment approach. The specimens, including sand, silty sand, silt, representing of the main sediment types recovered from the gas hydrate distribution region of the Eastern Nankai Trough, were tested. The obtained results from the experiments clearly indicate a particle size and clay content dependent trend, being low in saturation in fine sediment but high in coarse sediment. These results are generally consistent with NMR logging results for high-saturation samples, but somewhat different for samples with medium or low saturation levels. For a better understanding of the mechanism of these two factors, studies have been carried out to investigate the saturation level of methane hydrate in a series of silica powders and clay. The results obtained indicate that particle size and clay contents are the two key factors determining the saturation level of gas hydrate in sediments: the finer the particle size and/or the higher the clay content, the lower the hydrate saturation. It has been found that fundamentally the effect of particle size or clay mineral on hydrate saturation level can be accredited to specific surface area of sediment. This study was carried out as a part of the research undertaken by The Research Consortium for Methane Hydrate Resources in Japan (MH21). 11555 Reservoir Characterization and CO2-EOR Injection Studies in Chicontepec Turbidite Reservoirs, Mexico International Petroleum Technology Conference 2008/12/3-5 Maghsood Abbaszadeh (Innovative Petrotech Solutions Inc), Kenji Ohno, Hirofumi Okano (Japan Oil, Gas and Metals National Corporation), Jorge Morales, Juan Manuel Riano Caraza (Petroleos Mexicana) EOR Research Division ［Abstract］Chicontepec fields are tight elastic deposits comprised of stacked turbiditic events with extreme geological heterogeneity and variable heavy oil content. Huge reserves of oil are left behind because of loss of system energy by primary depletion; offering challenging opportunities for IOR/EOR processes. We first present a general methodology for integrated geostatistical reservoir characterization, using the technique of multivariate multiGaussian formalism for the integration of data sources and scales. The resulting geostatistical models are calibrated to available production data, and used as predictive tools for CO2-EOR and alternative solvent injection studies in simulated sector model pilots. In addition to CO2, the paper discusses injection of associated gas (NGL), N2, CH4, flue gas and their mixtures with CO2. Studies are performed to reduce MMP of Chicontepec oil with enriched CO2 and hydrocarbon mixtures, and a procedure is devised for enhanced MMP predictions. Continuous water and CO2 injection studies determine limiting values for injectivity and incremental recovery factors. WAG studies for mobility control and improved sweep determine optimum WAG ratio to be 1-3. MMP studies illustrate variability in fluid PVT and the required injection pressure ranges for miscibility. The CO2 utilization factor is less than 10 Mscf/bbl, indicating economic viability. EOR recovery factors in excess of 20% are possible for these tight rocks; depending on oil characteristics, MMP of solvents and geology of specific pilot sites. This high recovery efficiency is remarkable as contrasted with the 2-5% primary recovery factor established by 20-30 years of production history. Key parameters are identified that impact oil recovery in Chicontepec reservoirs, and it is demonstrated that flue gas (and hence N2) and associated gas injections mainly act as pressure maintenance agents because they are immiscible displacements. 11554 Technical challenge of GTL technology International Petroleum Technology Conference 2008/12/3-5 Yoshifumi Suehiro (Japan Oil, Gas and Metals National Corporation), Nobuyuki Osawa (Nippon GTL Technology Research Association) Research Project Team on Emerging Gas Technologies ［Abstract］1. Abstract 2. Introduction 3. Characteristic of JAPAN-GTL process 4. Results and discussion 5. Conclusion 11553 NGH Chain: A New Gas Transportation Concept International Petroleum Technology Conference 2008/12/3-5 Tatsuji Kawasaki, Katsuhiko Bando, Yoshifumi Suehiro (Japan Oil, Gas and Metals National Corporation) Research Project Team on Emerging Gas Technologies ［Abstract］In general LNG chain is economically feasible for natural gas reserve with sizable volume over several Trillion Cubic Feet (TCF) and long distant transportation projects. Feasibility studies reported so far have appeared that Natural Gas Hydrate (NGH) chain (production, ocean transportation, and re-gasification ) had economical advantage, particularly under a certain condition with suitable size of gas reserve and transportation distance. JOGMEC and Japanese engineering companies have recently focused on the NGH chain as a new gas transportation concept. Particularly the production process greatly impacts on a reduction of the total capital cost. Therefore JOGMEC and Japanese engineering companies have promoted the development of NGH production process since 2001. We has developed the bubbling/stirring-type formation reactor, the water-spraying-type formation reactor, and a new hydrate formation system which uses micro-bubbles with tubular reactor and higher formation rate over other systems has been obtained by micro-bubbles-type. In the near future, it is further needed to improve the precision of the feasible study along with an advance of the technology development to find out to what extent NGH technology has the potential to compete effectively with LNG technology. For that, it is important not only to consider an optimization of one process but also to understand an impact of one process on the chain and an optimization of entire NGH chain. 11552 3D seismic geomorphological analysis of submarine-fan turbidite reservoir distributions and shape variations using seismic facies and sedimentological information: examples from active margin basins International Petroleum Technology Conference 2008/12/3-5 Osamu Takano (Japan Oil, Gas and Metals National Corporation), Mizue Nishimura (Japan Petroleum Exploration Co., Ltd.), Tatsuo Saeki, Tetsuya Fujii (Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Division ［Abstract］3D seismic geomorphological analysis of submarine-fan turbidite reservoir distributions and shape variations using seismic facies and sedimentological information: examples from active margin basins 11551 Future Hydrocarbon Resource Methane Hydrate BioMarine Forum 2008 SESSION Extracting energy from the sea: Emergent technologies 2008/10/22 Kenji Ono (Japan Oil, Gas and Metals National Corporation) Technology Research & Development Department ［Abstract］Future Hydrocarbon Resource Methane Hydrate 11549 Oil Sands Reservoir Monitering Using Time-lapse 3D Seismic in Canada International Petroleum Technology Conference 2008/12/3-5 Toru Nakayama, Akihisa Takahashi (Japan Petroleum Exploration Co., Ltd.), Leigh Skinner (Japan Canada Oil Sands Limited), Ayato Kato (Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Division ［Abstract］Time-lapse 3D seismic monitoring study was conducted in the Hangingstone steam assisted gravity drainage (SAGD) operation area, Alberta, Canada. The objective of the study was to delineate areas of the reservoir infiltrated by steam using differences between two vintages of 3D seismic for efficient reservoir management. The time-lapse surveys were acquired in February, 2002 and in March, 2006. As repeatability is important for the time-lapse survey, the two 3D seismic surveys were recorded with near identical field acquisition parameters and the data sets of both surveys were processed with identical processing flows. In addition, 3D P-SV converted wave processing and analysis were conducted using the second 3D seismic data recorded with three-component digital sensors for reservoir characterization study. P-wave and S-wave velocities of oil sands core samples were also measured with various pressures and temperatures, and the laboratory measurement results were combined to obtain a rock physics model to predict velocity changes induced by steam-injection. The two seismic volumes show large differences in seismic character within the reservoir and time delays below the reservoir around the active SAGD well pairs. In order to evaluate seismic response changes of the time-lapse surveys, synthetic seismic data were analyzed under various reservoir conditions during the SAGD process based on the rock physics model. From our time-lapse data analysis, the differences of the seismic responses between the time-lapse seismic volumes can be quantitatively explained by P-wave velocity decrease of the oil sands layers due to the injection of steam. In addition, the data suggests that a larger area is influenced by pressure than by temperature. In conclusion, our analysis of both time-lapse 3D seismic and 3D P-SV data along with the rock physics model can be used to monitor qualitatively and quantitatively the rock property changes of the inter-well reservoir sands in the field. 11547 NANOSCALE PORE STRUCTURE OF CARBONATE ROCK RECONSTRUCTED BY GEOSTATISTICAL APPROACH VIII INTERNATIONAL GEOSTATISTICS CONGRESS (GEOSTATS 2008) 2008/12/1-5 Hiroshi Okabe (Japan Oil, Gas and Metals National Corporation) EOR Research Division ［Abstract］Connectivities of pores have significant impact on petrophysical properties, such as permeabilities on reservoir rocks. Micro-CT imaging is useful to visualize the microstructure of the rock, but it is still difficult to analyze nano/micro-scale connectivities. Multiple-point statistics with a two-dimensional (2D) image is used to reproduce the connectivities of pores. It is shown that inclusion of larger pores associated with smaller pores results in reasonable connectivities and the inclusion of nano/microporosity has a dramatic effect on the petrophysical properties. Three-dimensional (3D) imaging and analysis of carbonate core material at the nano/micro scale can provide a basis for more accurate petrophysical models, narrow the range of uncertainty in estimates of petrophysical properties and improve the quantification of the resource within carbonate reservoirs. 11545 Methane Hydrate Production; as Transport Phenomena 5th International Conference on Fluid Dynamics 2008/11/17 Koji Yamamoto (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Intended gas hydrate dissociation processes and techniques in geologic formation are studied for future commercial gas production from the "Fiery Ice." Because the stability of the material is governed by temperature and pressure conditions, the efficiency and productivity of the gas production are mainly controlled by how effective heat and fluid can be transported in sediments as porous media. The effectiveness of a production technique highly depends on the natural conditions that are related to transport parameters of heat and fluid. Some knowledge learnt from the recent gas production tests are shown with the theoretical background. 11544 Next Generation Hydrocarbon Resources Methane Hydrate-Accumulated E&P Technology in Japan The Commemorative International Symposium on the 50th Anniversary of the Japan Petroleum Institute 2008/11/5 Kenichi Yokoi (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Next Generation Hydrocarbon Resources Methane Hydrate - Accumulated E&P Technology in Japan 11543 Removal of Overburden Channeel Effects through Channel Velocity Modeling and Prestack Depth Migration for an oil field offshore Abu-Dhabi ADIPEC 2008 2008/11/3-6 Mamoru Takanashi (Japan Oil, Gas and Metals National Corporation), Mitsuyoshi Kaneko, Nobuaki Monzawa (ADOC) Geology & Geophysics Research Division ［Abstract］We achieved generation of refined reservoir structure through channel velocity modeling and application of PSDM. Although the amount of artifact on the target reservoir generated with Prestack time migration (PSTM) is relatively small, the artifact could give significant influence over prediction of oil saturation and production rate on the very gentle target reservoir. Investigation on the forward modeling indicate that precise channel velocity modeling and application of Prestack depth migration (PSDM) are ideally required for removing such artifacts. Detailed time interpretation delineated three channel locations and thicknesses, and pull-up/push-down distribution along a shale reflector just below the channel, which enable us to produce precise velocity model containing channel velocities. PSDM with the channel velocity model enabled us to distinguish between channel-associated artifacts and true geological events on the target reservoir and contributed generation of a refined reservoir structure. Since the sedimentology around the target oil/gas field would be similar, this approach could contribute reducing depth uncertainly for surrounding fields. 11542 "Methane Hydrate Exploration in the Eastern Nankai Trough" SEG2008/International Showcase Global Theatre "Asis/Pacific: An Ocean of Opportunity" 2008/11/12 Tatsuo Saeki, Takao Inamori (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Aiming commercialization of methane hydrate production, the Research Consortium for Methane Hydrate Resources in Japan (MH21) has carried out geological and geophysical surveys around the eastern Nankai Trough since 2001 as a nation project. Interpretation and analysis studies based on 2D/3D reflection seismic surveys, multi-wells drilling campaign and other geological surveys revealed existences of methane hydrate concentrated zones, of which reserves were constructed with turbidite sand layers. In the view of resource explorations, methane hydrate concentrated zones, which can save much amount of methane hydrate locally, are more attractive than other methane hydrate bearing zones. We developed the geological interpretation procedure optimized for delineation of methane hydrate concentrated zones. The workflow consists of identifications regarding following 4 indicators: (1) BSR, (2) turbidite sequence (above BSR), (3) strong seismic reflectors and (4) relatively higher interval velocity, suggesting methane hydrate concentrated sand layers. It enabled us to delineate methane hydrate concentrated zones and evaluate their rock volume successfully in the eastern Nankai Trough. 11541 The Progress of Aurora-JOGMEC-NRCan Mallik 2006-2008 Gas Hydrate Research Project Fire in the Ice (USDOE National Energy Laboratory Newsletter) Summer, 2008 2008/7 Koji Yamamoto (Japan Oil, Gas and Metals National Corporation), S.R.Dallimore (Natural Resources Canada) Methane Hydrate Research Project Team ［Abstract］The Progress of Aurora-JOGMEC-NRCan Mallik 2006-2008 Gas Hydrate Research Project 11540 EXPERIMENTAL INVESTIGATION OF RESIDUAL CO2 SATURATION DISTRIBUTION IN CARBONATE ROCK International Symposium of the Society of Core Analysts 2008/10/29-11/2 Hiroshi Okabe, Yoshihiro Tsuchiya (Japan Oil, Gas and Metals National Corporation) EOR Research Division ［Abstract］In order to visualize and understand the CO2 saturation distribution in the rock, the coreflood experiment is conducted with in-situ saturation monitoring by X-ray CT. Residual CO2 saturation by capillary trapping is observed on the Middle Eastern carbonate rock. 11536 A New Syngas Production Process for GTL 2008 SPE APOGCE 2008/10/20 Yoshifumi Suehiro (Japan Oil, Gas and Metals National Corporation), Yoshiyuki Watanabe, Akira Sugimoto (JGC Corporation), Kota Yakoyama, Koichiro Ikeda, Naoki Ikeda (Osaka Gas Co., Ltd.) Research Project Team on Emerging Gas Technologies ［Abstract］Abstract Introduction Results and discussions Conclusion (1)The pilot plant tests verified the performance of the AATG Process and provided the data and information needed for the design of a demonstration and a commercial plant. (2)The AATG Process is an economical and environmentally-friendly process. Especially its characteristics will explore applications in not only a large size of gas field such as in Middle East but also a medium size of hydrocarbon resource such as an associated gas, a flare gas and a coal seam gas. (3)The AATG has a potential to load on FPSO. We still develop ongoing this research. 11534 Elastic property changes of bitumen reservoir during steam injection Intereseted rock physics group 2008/10/15 Ayato Kato, Shigenobu Onozuka (Japan Oil, Gas and Metals National Corporation), Toru Nakayama (Japan Petroleum Exploration Co., Ltd.) Geology & Geophysics Research Division ［Abstract］Heavy oil and bitumen have become tremendously important resources for us in this decade. Several of their physical properties are significantly different from conventional oil such as higher viscosity, higher density, higher seismic attenuation, and higher velocity dispersion (e.g., Batzle et al., 2006; Behura et al., 2007). One of the most effective methods for producing the bitumen in Canada is the Steam-Assisted Gravity Drainage (SAGD) method. It makes the bitumen flowable by heating it with injected steam and reducing its viscosity. The steam movement is highly influenced by complex substructures in reservoir. The time-lapse seismic survey is expected to be powerful for monitoring the three-dimensional steam movement. However, the difficulties of making quantitative interpretation of the time-lapse seismic data remain because there has been no model of relating seismic velocities of bitumen-saturated sediments (oil sands) directly with reservoir parameters (temperature, pressure, and fluid saturation). We measured and analyzed the ultrasonic velocities of the oil sands cores acquired from the SAGD operation area in order to understand the relationship between elastic properties of the oil sands and changes in temperature and pore pressure. As a result, we constructed the sequential rock physics model which allow us to predict velocity changes of the oil sands caused by any variations of pore pressure, temperature, fluid saturation and fluid phase changes expected during the steam injection. We also discuss the velocity dispersion using VSP, sonic, and the core velocity measurement data. We propose a practical method for calibrating the velocity dispersion and obtain the new sequential rock physics model which is adapted for the low frequency band of the surface seismic. In accordance with the new model, we predict elastic property changes induced by the steam injection. 11530 Methane hydrate bearing sediments: a new subject of geomechanics 12th International Conference of IACMAG (International Association for Computer Methods and Advances in Geomechanics) 2008/9/30-10/6 Koji Yamamoto (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Methane clathrate hydrate (MH) bearing sediments related Geomechanics issues are summarized. Mechanical properties of MH bearing sediments highly depend on the saturation of MH, pressure and temperature and structure of it in pore spaces. Such mechanical properties influence various scales of geological formation stabilities. Because the stability of MH is a function of temperature and pressure, the mechanical behavior of the material is coupling phenomena of mechanics to fluid dynamics and heat transfer phenomena. Also the host sediments are relatively shallow unconsolidated or weakly consolidated sand, silt or clay, and there behavior itself is complex. To understand the physical and mechanical processes, all of the elements stated here should be taken into account. 11529 Elastic property changes of bitumen reservoir during steam injection The Leading Edge 2008/9/1 Ayato Kato, Shigenobu Onozuka (Japan Oil, Gas and Metals National Corporation), Toru Nakayama (Japan Petroleum Exploration Co., Ltd.) Geology & Geophysics Research Division ［Abstract］Elastic property changes of bitumen reservoir during steam injection 11528 Monitoring an oil-sands reservoir in northwest Alberta using time-lapse 3D seismic and 3D P-SV converted-wave data The Leading Edge 2008/9/1 Toru Nakayama, Akihisa Takahashi (Japan Petroleum Exploration Co., Ltd.), Leigh Skinner (Japan Canada Oil Sands Limited), Ayato Kato (Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Division ［Abstract］Monitoring an oil-sands reservoir in northwest Alberta using time-lapse 3D seismic and 3D P-SV converted-wave data 11525 Formation evaluation of free gas zone beneath bottom simulating reflector 14th Formation Evaluation Symposium of Japan 2008/9/29-30 Hitoshi Mikada (Kyoto University), Takao Inamori, Tatsuo Saeki (Japan Oil, Gas and Metals National Corporation), Katsuko Suzuki （Schlumberger), Kyosuke Onishi (Kyoto University) Methane Hydrate Research Project Team ［Abstract］Geologists and Geophysicists think that layers of free gas are underlie beneath the bottom simulating reflectors in methane hydrate studies. The existence of free gas below any methane hydrate concentrated zones is of importance to study how the methane is produced and migrated in ocean sediments to form methane-enriched zones. However, no one has really studies how much gas is in place in the free gas zones. What we observe in Nankai trough methane hydrate studies are characterized as abrupt change in compressional wave velocity in the seismic band and several percent change in sonic phase velocities. These observations do not satisfy the conditions proposed by the gas sand model that has been proved a very efficient method to quantitatively evaluate volume fraction of gas in the formation fluid using the delay in sonic travel time. To cope with this problem of the discrepancy in the change of seismic and sonic wave velocities in the free gas layers, we introduce a new model for the free gas layers that satisfies our observations in seismic and sonic phase velocities and discuss why the gas sand model may not be applied to the analysis of free gas layers. Finally, we try to summarize how free gas is in place in the formation water not only in the free gas layers but in the methane hydrate steady zones above the bottom simulating reflectors. 11524 The rock physics model of methane hydrate-bearing sediments 14th Formation Evaluation Symposium of Japan 2008/9/29-30 Takao Inamori, Tatsuo Saeki (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］It is well known the methane hydrate exists at the sea floor below 500m or arctic under the frozen ground in the nature. Helgerud (2001) proposed the four methane hydrate-bearing rock physics models such as Contact cementing model, Grain-coating model, Matrix-supporting model and Pore-filling model. Helgerud (2001), Dai et al. (2004), Hato et al. (2006) clarified the relationships between P-wave velocity (Vp), S-wave velocity (Vs), P- and S- wave velocity ratio (Vp/Vs) and the methane hydrate saturation (Smh) from those models. Hato et al. (2006) inferred methane hydrate-bearing type would be the Matrix-supporting model at the MITI Nankai Trough wells from the analysis of Vp, Vs, Vp/Vs and methane hydrate saturation. However, there is some error with the Vp, Vs and Vp/Vs from the model and real well sonic data. First, in this study we evaluated the effect of sand/clay content change the P-wave velocity on the matrix-supporting rock physics model. The sand volume decreases, the Vp and Vs decrease, and Vp/Vs increases. The analysis of sand content from the logging data or core data in the Mackenzie delta wells in Canada are inferred the about 90 % sand content. It is good correspondence between the real Vp, Vs, Vp/Vs and the values from matrix-support model data. On the other hand, the analysis of sand content from the logging data or core data in the Eastern Nankai Trough wells are inferred the about 40 or 50 % sand content. The Vp, Vs and Vp/Vs values corresponded to the data from the matrix-support model with 40 or 50 % sand content. In the Eastern Nankai Trough and the Mackenzie delta, it is inferred the methane hydrate saturation delineate from Vp, Vs and Vp/Vs to assume the methane hydrate-bearing sediments as the Matrix-supporting model. These result will apply the approach to delineate the methane hydrate saturation or concentration from Vp, Vs or Ip, Is, or Vp/Vs by the seismic data. 11523 Gas Hydrate Reservoir Model Around the Eastern Nankai Trough-Offshore Japan SEG/EAGE SUMMER RESEARCH WORKSHOP 2008/9/7-11 Takao Inamori, Tatsuo Saeki (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］The methane hydrate-bearing sediments around the Eastern Nankai Trough area are heterogeneous and complex both vertically and horizontally, because methane hydrate-bearing zones are mainly turbidite sands - channel-levee or lobe sediments. Methane hydrate reservoirs are distinguished into three types by the well logging data mainly the resistivity and the P- or S- wave velocity. One is the low-saturation reservoir type, second is the discontinuous high-saturation reservoir type, last is the continuous high-saturation reservoir type, and also we call the methane hydrate-concentrated zone as high-saturation reservoir type. Our main exploration target is the continuous high-saturation reservoir type, as the methane hydrate-concentrated zone. We delineated the methane hydrate-concentrated zones around the Eastern Nankai Trough area, by the picking the strong reflections as the top of methane hydrate-concentrated zones which are assumed the turbidite channel-levee or lobe system and by the P-wave interval velocity profile from high dense velocity analysis data. We delineated the methane hydrate-concentrated zones around the Eastern Nankai Trough area, by the picking the strong reflections as the top of methane hydrate-concentrated zones which are assumed the turbidite channel-levee or lobe system and by the P-wave interval velocity profile from high dense velocity analysis data. Furthermore, we reviewed the P or S wave velocity and the methane hydrate saturation at the wells in the methane hydrate-bearing zone. We estimated the matrix-support model from the relationship between the P or S wave velocity and the methane hydrate saturation. This study is a part of the research results of MH21 project conducted by Japan Oil, Gas and Metals National Corporation (JOGMEC). 11522 THE ROCK PHYSICS MODEL OF METHANE HYDRATE-BEARING SEDIMENTS SEG/EAGE SUMMER RESEARCH WORKSHOP 2008/9/7-11 Takao Inamori, Tatsuo Saeki (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Helgerud (2001), Dai et al. (2004), Hato et al. (2006) clarified the relationships between P-wave velocity (Vp), S-wave velocity (Vs), P- and S- wave velocity ratio (Vp/Vs) and the methane hydrate saturation (Smh) from those models. Hato et al. (2006) inferred methane hydrate-bearing type would be the Matrix-supporting model at the MITI Nankai Trough wells from the analysis of Vp, Vs, Vp/Vs and methane hydrate saturation. However, there is some error with the Vp, Vs and Vp/Vs from the model and real well sonic data. First, in this study we evaluated the effect of sand/clay content change the P-wave velocity on the matrix-supporting rock physics model. The sand volume decreases, the Vp and Vs decrease, and Vp/Vs increases. In the Eastern Nankai Trough and the Mackenzie delta, it is inferred the methane hydrate saturation delineate from Vp, Vs and Vp/Vs to assume the methane hydrate-bearing sediments as the Matrix-supporting model. These result will apply the approach to delineate the methane hydrate saturation or concentration from Vp, Vs or Ip, Is, or Vp/Vs by the seismic data. This study is a part of the research results of MH21 project conducted by Japan Oil, Gas and Metals National Corporation (JOGMEC). 11520 Changes in Submarine Fan Sedimentation Processes in Response to Force Basin Tectonics along the Nankai Trough, Philippine Plate Subduction Zone 6th International Conference on Asian Marine Geology 2008/8/31 Osamu Takano (Japan Oil, Gas and Metals National Corporation), Mizue Nishimura (Japan Petroleum Exploration Co., Ltd.), Tetsuya Fujii, Tatsuo Saeki (Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Division ［Abstract］Changes in Submarine Fan Sedimentation Processes in Response to Force Basin Tectonics along the Nankai Trough, Philippine Plate Subduction Zone 11519 Possible fluid and gas migration inferred from detailed 3D-seismic interpretation in the eastern Nankai Trough 6th International Conference on Asian Marine Geology 2008/8/30 Hironori Otsuka, Sumito Morita, Manabu Tanahashi (AIST), Juichiro Ashi (The University of Tokyo), Sasao Nagakubo, Tetsuya Fujii (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］BSRs (Bottom Simulating Reflectors) on multichannel seismic reflection profiles are widely distributed in the trench inner slope and the forearc basins of the Nankai Trough. The eastern part of the Nankai Trough, moreover, is well-examined by coring and logging-while-drilling (LWD) in METI(Ministry of Economy, Trade and Industry) exploratory test wells “Tokai-oki to Kumano-nada” drilled in 2004. For the drilling site survey, high resolution 3D seismic survey, “Tokai-oki to Kumano-nada”, was conducted for methane hydrate investigation in the eastern Nankai Trough by METI in 2002. This survey revealed detailed distributions of BSRs probably controlled by lithology and structure. Our study focuses on distinct reflectors which fold back from BSR margins and repeat foldbacks once or several times exhibiting bellows-like shape. These reflectors are called “Foldback Reflectors (FBRs)” in this study. FBRs are observed in the area adjacent to the Tenryu Canyon and the Ryuyo Canyon, the southeastern side of the Daiichi Tenryu Knoll and the area around the northern slope of the Daini-Atsumi Knoll. From the edge of BSR, FBR generally extends down to lower formation below the BSR, crossing the formation. This reflector is called the 1st FBR. Since the 1st FBR often show a foldback to the further lower formation, this secondary reflector is called the 2nd FBR, which extends outward below the 1st FBR. It is not rare that the following FBRs (the 3rd and above) occur below the prior FBR, where each reflector extends down to the lower formation from a foldback at the end of the last FBR, but it horizontally goes to the opposite direction of the last one’s. Thus, these connected zigzag-shaped (bellows-like) reflectors totally show a series of FBRs at the edge of BSRs. The 1st FBR indicates normal polarity (antiphase of BSR). In contrast, the 2nd FBR is showing reversed polarity. In the same way, the following FBRs change their polarities alternately. Although 3D seismic data exhibits various shapes of FBR according to lithology and structure of formation, polarity of each FBR is laterally successive, crossing those formations. Additionally, FBR generally corresponds to lateral acoustic phase boundary in the successive formation, where the formation within the FBRs (beneath the BSR distribution area) shows relatively low amplitude and lack of high frequency components, in contrast to the area beyond the FBRs (outside the BSR area) which shows clear stratification. Seismic velocity analysis (JOGMEC, unpublished data) suggests that FBRs correspond to velocity boundaries as well. The formation within the FBRs indicates relatively low velocity as compared with beyond the FBRs, where the FBRs often indicates sharp and rapid change in velocity. The polarities of FBRs are also consistent with such velocity changes. Consequently, low velocity regions coincide with the portions with low amplitude and lack of high frequency components. Such low velocity and amplitude anomaly suggests relation to gas components in the formation water. In addition, high amplitude layers are sometimes recognized at foldbacks convex to the outside. These high amplitude layers probably having higher permeability are interpreted as conduits of gas-related fluid from the BSR area side to the no BSR side. From these facts, we conclude that FBR can be regarded as important proxy indicating migration front of gas-related fluid. 11512 Elastic Property Changes of Bitumen Reservoir during Steam Injection SEG 2008 Summer Research Workshop 2008/7/22 Ayato Kato, Shigenobu Onozuka (Japan Oil, Gas and Metals National Corporation), Toru Nakayama (Japan Petroleum Exploration Co.,Ltd.) Geology & Geophysics Research Division ［Abstract］Elastic property changes of bitumen reservoir during steam injection have been poorly understood. We measured and analyzed ultrasonic velocities of bitumen-saturated sediments (oil sands) and then obtained a relation of the velocities with temperature and pressure individually. We also investigated validity of the Gassmann equation for predicting velocity changes and confirmed that the Gassmann equation can be applicable at temperatures greater than 80 °C. We combined the laboratory measurement results to obtain a sequential rock physics model that can predict the velocity changes induced by the steam injection. We predicted elastic property changes during the steam injection according to the rock physics model. P-wave velocity is a relatively all-around player for distinguishing steam fronts, while S-wave velocity can be used only for distinguishing a gentle-warmed area 11510 Delineation of methane hydrate concentrated zone using 3D data in the Eastern Nankai Trough 6th International Conference on Gas Hydrates 2008/7/10 Tatsuo Saeki, Tetsuya Fujii, Takao Inamori, Toshiaki Kobayashi, Sadao Nagakubo, Osamu Takano (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Aiming commercialization of methane hydrate production, the Research Consortium for Methane Hydrate Resources in Japan (MH21) has carried out geological and geophysical surveys around the eastern Nankai Trough since 2001 as a national project. Interpretation and analysis studies based on 2D/3D reflection seismic surveys, multi-wells drilling campaign and other geological surveys revealed existences of methane hydrate concentrated zones, of which reserves were constructed with turbidite sand layers. In the view of resource explorations, methane hydrate concentrated zones, which can save much amount of methane hydrate locally, are more attractive than other methane hydrate bearing zones. We developed the geological interpretation workflow optimized for delineation of methane hydrate concentrated zones. The workflow consists of identifications regarding following 4 indicators: (1) BSR, (2) turbidite sequence (above BSR), (3) strong seismic reflectors and (4) relatively higher interval velocity, suggesting methane hydrate concentrated sand layers. It enabled us to extract methane hydrate concentrated zones and evaluate their rock volume successfully in the eastern Nankai Trough. 11509 Study results of picking high amplitude reflectors in turbidite channel to reveal detail of methane hydrate concentrated zone 6th International Conference on Gas Hydrates 2008/7/10 Naoyuki Shimoda, Tatsuo Saeki, Takao Inamori, Toshiaki Kobayashi, Tetsuya Fujii (Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Division ［Abstract］3D seismic surveys were conducted in the eastern Nankai Trough by METI in 2002 to evaluate methane hydrate resource potential. In this area, more than 10 methane hydrate concentrated zones which are characterized by turbidite sand bodies were delineated and roughly classified into channel and lobe type. Channel type methane hydrate concentrated zones are recognized by strong amplitude reflector patches within channel complexes above BSR. The high amplitude reflector patches represent sand bodies which contain much methane hydrate, thus it is possible to discuss the 3D feature of a channel development and internal structures of channel type methane hydrate concentrated zones by picking these reflector patches. In this study, we focused one channel type methane hydrate concentrated zone. Picked reflector patches showed that the methane hydrate concentrated zone is biforked at lower current area. Detailed observation revealed that the methane hydrate concentrated zone is developed in a channel complex of which conduit was shifted little by little. Additionally, by comprehensive interpretation of the amplitude characters, the relative position and their continuity, reflector patches were grouped within each channel. Amplitude attribute of the grouped reflector patches provided a clue to identify which reflector patches are generated by main channel current sand bodies. It means that it is possible to find out reflector patches which have good reservoir properties. Such evaluation of the properties of the sand bodies will contribute to the future precise volume estimation of methane hydrates, and also to the detailed geological model construction for production simulation. 11508 2D MULTI-COMPONENT SURVEY OVER METHANE HYDRATE DEPOSITS IN THE NANKAI TROUGH 6th International Conference on Gas Hydrates 2008/7/10 Peter Ward, Eiichi Asakawa, Huda Allawati (JGI, Inc.), Tatsuo Saeki, Takao Inamori, Naoyuki Shimoda (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］A small 2D multi-component seismic survey was carried out using the new RSCS (Real-time Seismic Cable System) system in methane hydrate bearing zone in the Nankai Trough in order to delineate the S-wave characteristics of hydrates. The RSCS is an ocean bottom cable system employing a series of 3 component geophones connected with submarine optical cable. One deployment has 18 receivers with a spacing of 50m, which covers 850m line length. The 3 component data was acquired on the seafloor over two well locations and part of a conventional streamer 3D survey. The survey consisted of 3 receiver lines; the first line is intersecting over the well locations with 4 deployments of RSCS, the second and third one are crossing the first line on the each well location with 1 and 2 deployments, respectively. A sea-surface airgyn system is used as source with a spacing of 25m. The quality of the field data is excellent with high vector fidelity. The vertical component data was imaged using P-wave OBS pre-stack time migration, including Vp migration velocity analysis. The resulting sections showed excellent agreement with the 3D survey migrated data volume. The in-line horizontal component data was imaged using C-wave (PS converted wave) OBS pre-stack time migration, including Vc migration velocity analysis and updates to the gamma ratios. The resulting C-wave sections showed amplitude anomalies at the BSR level. This fact indicates S-wave velocity anomaly and gives useful information to estimate the rock physics model of the methane hydrates in this area. 11507 Detailed Inner structure of methane hydrate concentrated zone of lobe type 6th International Conference on Gas Hydrates 2008/7/8 Toshiaki Kobayashi, Tatsuo Saeki, Takao Inamori, Tetsuya Fujii, Naoyuki Shimoda (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Japan Oil, Gas and Metals National Corporation (hereinafter called JOGMEC), as a member of MH21 Research Consortium, takes charge of a study of the Research for Resources Assessment, and is pursuing a possibility that the methane hydrate, which is presumed to be distributed around ocean area of Japan, will be energy resources. JOGMEC is currently conducting analysis of the seismic data which was acquired by 3D seismic survey conducted from Tokaioki to Kumanonada in the eastern Nankai Trough by METI (Mnistry of Economy, Trade and Industry) in 2002 under the national program of assessment for methane hydrates as energy resources. The seismic data was analyzed by the knowledge that the methane hydrates were correlated to high resistivity and high velocity based on the results of drilling surveys and velocity analysis, and more than 10 methane hydrate concentrated zones have been extracted. In the view of the seismic geomorphology, methane hydrates were concentrated in the turbidite sand layers and the concentration configurations can be roughly classified into the channel type and the lobe type. In this study, the detailed analysis of the inner structure of the methane hydrate concentrated zone of the lobe type was conducted to understand the occurrence configurations of the methane hydrates. The reflected waves construct the methane hydrate concentrated zones in the seismic data were extracted and those reflected waves were classified into some groups every one reflector. As the results, many reflectors construct the methane hydrate concentrated zones were interpreted. Those reflectors at wells were correlated to the top of the methane hydrate bearing sand layers, and the amplitude variation of the reflected waves correlated to the sand layers shows the concentration distribution of the methane hydrates and it will be expected to understand the distribution of the sand layers and the change of the properties of the methane hydrates. 11506 Experimental Studies of the Saturation Level of Methane Hydrate in the Eastern Nankai Trough Sediments 6th International Conference on Gas Hydrates 2008/7/8 Tatsuji Kawasaki, Tetsuya Fujii, Masaru Nakamizu (Japan Oil, Gas and Metals National Corporation), Hailong Lu, John A.Ripmeester (National Research Council of Canada) Methane Hydrate Research Project Team ［Abstract］The pore saturation of natural gas hydrate in sediments is a key for estimating hydrate resources in a reservoir. For a better understanding of gas hydrate distribution, the experimental study of the pore saturation of methane hydrate in sediments from a hydrate reservoir in the Eastern Nankai Trough have been carried out. In total, eleven samples, comprising sand, silty sand, silt, and representative of the main sediment types identified in the Eastern Nankai Trough, were tested. The results obtained clearly indicate a particle size and clay content dependent trend: almost 100% of pores were saturated with methane hydrate in sand when little silt and clay were present, decreasing to 〜13% in silty sand (sand 54%, silt 41% and clay 5%), and 〜4% in clayey silt. These results are generally consistent with NMR logging results for high-saturation samples, but somewhat different for samples with medium or low saturation levels. 11486 Methane Accumulation and Formation High Saturations of Methane Hydrate in Sandy Sediments 6th International Conference on Gas Hydrates 2008/7/6-10 Takasi Uchida (University of Calgary), Amane Waseda (Japan Petroleum Exploration Co., Ltd.), Tetsuya Fujii (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］In 1998, 2002 and 2007 Mallik wells were drilled in the Canadian Arctic that clarified the characteristics of gas hydrate-concentrated sandy layers at depths from 890 to 1110 m beneath the permafrost zone. Continuous downhole well log data, anomalies of chloride contents in pore waters, core temperature depression as well as visible gas hydrates have confirmed the highly saturated pore-space hydrate, whose saturations are evaluated higher than 80% in pore volume. In the Nankai Trough forearc basins and accretionary prisms developed and BSRs have been recognized widely, where the multiple wells were drilled in 2000 and 2004, and revealed the presence of pore-space hydrate in sandy layers. High concentration of gas hydrate may need original pore space large enough to occur within a host sandy sediment. The distribution of porous and coarser-grained sandy sediments is one of the most important factors controlling occurrences and distributions of gas hydrate, as well as physicochemical conditions. Supplying methane for forming deep marine gas hydrate is commonly attributed to microbial conversion of organic material within the zone of stability or to migration of methane-containing fluids from a deeper area. Pore water flows are considered to a macroscopic migration through faults/fractures and a microscopic flow in intergranular pore systems of sediments. Gas migration processes are estimated to be an active flow to permeable sandy layers in Nankai Trough, and a long migration of thermogenic gas generated in deeper mature sediments through faults in Mallik. It is remarked that there are many similar features in appearance and occurrence of highly saturated hydrate within sandy sediments in the terrestrial and the deep marine environment. This study was performed as a part of the Research Consortium for Methane Hydrate Resources in Japan (MH21). 11485 Velocity Profiles from Borehole Seismic in a Methane Hydrate Bearing Interval in the eastern Nankai Trough 6th International Conference on Gas Hydrates 2008/7/6-10 Katsuko Suzuki, Ai Katayama, Hiroaki Yamamoto, Philip Armstrong (Schlumberger), Doug Murray (Schlumberger Oilfield Services), Masafumi Fukuhara (Schlumberger Moscow Research), Tatsuo Saeki, Takao Inamori (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］To reveal the seismic velocity profiles (Vp and Vs) in a gas hydrate bearing interval in the eastern Nankai Trough, offshore of southeastern Japan, we carried out an offset vertical seismic profile (OVSP) survey to acquire converted shear waves in marine sediments as well as a zero offset VSP (ZVSP) survey. Vp and Vs from borehole seismic are useful information to identify and characterize the hydrate bearing interval. We clearly identified shear waves in the OVSP data. The mode conversion points were located at the top of the hydrate bearing interval, as well as at the top and bottom of a hydrate-concentrated zone. Using the converted shear waves in marine sediments as well as a zero offset VSP (ZVSP) survey. Vp and Vs from borehole seismic are useful information to identify and characterize the hydrate bearing interval. We clearly identified shear waves in the OVSP data. The mode conversion points ware located at the top of the hydrate bearing interval, as well as at the top and bottom of a hydrate-concentrated zone. Using the converted shear waves as well as direct waves from the ZVSP, compressional and shear wave velocities were estimated from travel time inversion and parametric inversion process. The computed interval velocities from the VSP were compared with velocities from sonic log. The results showed that both Vp and Vs interval velocities increased in the hydrate bearing zone and then decreased at the base of the zone. Within the hydrate-bearing interval, the seismic and sonic velocities and their trends showed reasonably good agreement. Below the hydrate zone, the shear velocities were in good agreement but the compressional velocities were significantly different, with the seismic Vp much smaller than the sonic Vp. These velocity discrepancies may be understood in terms of the difference in sensitivity to existing free gas for the different wavelength of the two difference in sensitivity to existing free gas for the different wavelengths of the two measurements. This work was supported by funding from the MH21 Research Consortium in Japan. 11483 Fault-tolerance design of motion control for offshore platform ATMA-ASSS 2008 Symposium 2008/6/4 Ikuo Yamamoto (The University of Kitakyushu), Hiroaki Hirayama (Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］This paper describes about the development of the new robust dynamic positioning system of offshore platform for offshore oil development. The system is developed by thruster force distribution control, and robustness of the system against failure of actuator is much improved and full operation against severe environmental condition can be executed. The effectiveness of the system was confirmed by computer simulations and real experiments. 11476 CO2-EOR Injection Studies in Chicontepec Fields The Mexican Petroleum Congress, Monterrey 2008 2008/5/28-31 M. Abbaszadeh (IPS)、Kenji Ohno, Hirofumi Okano(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］Chicontepec fields are tight clastic deposits comprised of stacked turbiditic events　with extreme geological and fluid heterogeneity. Huge reserves of oil are left behind　because of loss of system energy by primary depletion; offering challengingopportunities for IOR/EOR processes. Detailed geostatistical geological reservoir　models are first constructed and calibrated to the available primary and waterflood　performance data for use as predictive tools for CO2-EOR in three simulated pilot sector models in the fields of Tajin and Agua Fria. Alternative fluid injections of water,　associated gas, methane and flue gas are also considered in these studies. PVT and　EOS analyses are provided to gauge MMP of CO2 and other fluid injectants with Chicontepec oils of varying hydrocarbon composition. Detailed studies on various CO2 injection scenarios investigate applicability and limitations of CO2-EOR and provide information when CO2-EOR could be beneficial. Continuous water and CO2 injection studies determine limiting values for injectivity and incremental recovery factors. WAG studies for mobility control determine optimum WAG ratio, considering limitations on CO2 availability and unfavorable fluid and rock characteristics. MMP studies illustrate the significance of variability in fluid PVT and the required injection pressure range for achieving miscibility through a dimensionless injection pressure parameter. Advantages and disadvantages of associated gas, methane and flue gas injections are demonstrated. CO2-WAG ratios of 1-3 are determined to be optimum. The CO2 utilization factor is less than 10 Mscf/bbl, indicating economic viability. EOR recovery factors in excess of 20% are possible for these tight rocks, depending on the PVT, MMP and geology of specific pilot sites. This high recovery efficiency is remarkable as contrasted with the 2-5% primary recovery factor established by 20-30 years of production history. Key parameters are identified that impact oil recovery factor. Flue gas and associated gas injections are found to act as pressure maintenance because they are immiscible with Chicontepec oils that contain higher percentages of heavy-end hydrocarbon fractions. This presentation shows factors and process mechanisms that influence oil recovery in Chicontepec reservoirs. It is shown how optimum CO2 application schemes are identified by conducting a suite of sensitivity studies, which contribute to a deeper understanding of how reservoir and fluid characteristics are combined for oil recovery expectations. These studies illustrate the potential of CO2-EOR technology as an optimized oil recovery plan, and open possibilities for future enriched CO2 injection for improved miscibility. 11468 Japanese National Programs on the Methane Hydrate Research 6th International Workshop on Methane Hydrate Research & Development (Fiery ice)2008/5/13-16 Koji Yamamoto (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Japanese National Programs on the Methane Hydrate Research 11467 Resource Assessment of Methane Hydrate in the Eastern Nankai Trough, Japan 6th International Workshop on Methane Hydrate Research & Development (Fiery ice)2008/5/13-15 Tetsuya Fujii, Tatsuo Saeki, Toshiaki Kobayashi, Takao Inamori, Masao Hayashi, Osamu Takano, Tokujiro Takayama, Tatsuji Kawasaki, Sadao Nagakubo, Masaru Nakamizu, Kenichi Yokoi (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Resource assessment of methane hydrate (MH) in the Eastern Nankai Trough was conducted through probabilistic approach using 2D/3D seismic data and drilling survey data from METI exploratory test wells “Tokai-oki to Kumano-nada” We have extracted more than 10 prospective “MH concentrated zones” characterized by high resistivity in well log, strong seismic reflectors, seismic high velocity, and turbidite deposit delineated by sedimentary facies analysis. The amount of methane gas contained in MH bearing layers was calculated using volumetric method for each zone. Each parameter, such as gross rock volume (GRV), net-to-gross ratio (N/G), MH pore saturation (Sh), porosiry, cage occupancy, and volume ratio was given as probabilistic distribution for Monte Carlo simulation, considering the uncertainly of these evaluations. The GRV for each hydrate bearing zones was calculated from both strong seismic amplitude anomaly and velocity anomaly. Time-to-depth conversion was conducted using interval velocity derived from Seismic Vision While Drilling (SVWD). Risk factor was applied for the estimation of the GRV in 2D seismic area considering the uncertainly of seismic interpretation. The N/G was determined based on the relationship between LWD resistivity and grain size in zones with existing wells. Seismic ficies map created by sequence stratigraphic approach was also used for determination of the N/G in zone without well controls. Porosity was estimated using density log, together with calibration by core analysis. The Sh was estimated by the combination of density log and NMR log, together with the calibration by observed gas volume from onboard MH dissociation tests using Pressure Temperature Core Sampler (PTCS). The Sh in zone without well control was estimated using relationship between seismic P-wave internal velocity and Sh from NMR log at well location. Total amount of methane gas in place contained in MH within survey area in the eastern Nankai Trough was estimated to be 40 tcf as Pmean value. Total gas in place for MH concentrated zone was estimated to be 20 tcf (Half of total amount) as Pmean value. Sensitivity analysis indicated that the N/G and Sh have higher sensitivity than other parameters, and they are important for further detail analysis. 11466 Elastic Property Changes of Bitumen Reservoir during Steam Injection 2008 CSPG CSEG CWLS Convention 2008/5/12 Ayato Kato, Shigenobu Onozuka (Japan Oil, Gas and Metals National Corporation), Toru Nakayama (Japan Petroleum Exploration Co.,Ltd.) Geology & Geophysics Research Division ［Abstract］Elastic property changes of oil sands reservoir during steam injection are poorly understood. We measured and analyzed ultrasonic velocities of the oil sands and then obtained a relation of the velocities with temperature and pressure individually. We also investigated validity of the Gassmann equation for predicting velocity changes and confirmed that the Gassmann equation can be applicable at temperatures greater than 80℃. We combined the laboratory measurement results to obtain a sequential rock physic model that can predict velocity changes induced by steam injection. We predicted elastic property changes during the steam injection according to the model. P-wave velocity is a relatively all-around player for distinguishing steam fronts, while S-wave velocity can be used only for distinguishing a gentle-warmed area. 11465 NOC-JOGMEC Joint Study on “Produced Water Treatment and Oily Soil　Remediation” First International Petroleum Environmental Conference and Exhibition 2008/5/12 Hiroyuki Sekino (Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］1) JOGMEC has been conducting a joint study with Libya NOC regarding “Produced Water Treatment and Oily Soil　Remediation” on a few selected oil fields (model site). The study team consists of topnotch specialists on water treatment, soil remediation, NORM survey, GIS and plant engineering. Based on the environmental site survey of evaporation ponds and produced water in the model site conducted as Phase 1 (October-December2007) of the study, findings and subsequent practical countermeasures will be presented in the final report at the end of Phase 2 (January-October 2008). 2) In the site survey conducted during Phase 1, utilizing hand-held instruments such as multi parameter water quality monitoring system, several parameters of surface water and soil including pH, electrical conductivity, etc. were measured at over 50 spots and 14 samples were collected and later analyzed chemically at LPI and laboratories in Japan. 3) In Phase 2, sample collection in trenchs/pits is planned to identify oil contamination mechanism. We will also research on internationally-accepted laws and regulations in relation to environmental protection and try to come up with appropriate countermeasures adoptable in Libya. 11464 Extraction of methane hydrate concentrated zone for resource assessment in the Eastern Nankai Trough, Japan 2008 Offshore Technology Conference 2008/5/7 Tatsuo Saeki, Tetsuya Fujii, Takao Inamori, Toshiaki Kobayashi, Masao Hayashi, Sadao Nagakubo, Osamu Takano (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Aiming commercialization of methane hydrate development, the Research Consortium for Methane Hydrate Resources in Japan (MH21) has been executing geological and geophysical surveys around the eastern Nankai Trough since 2001 as a national project. 　Interpretation and analysis studies based on 2D/3D reflection seismic surveys, multi-wells drilling campaign and other geological surveys revealed existences of methane hydrate concentrated zones, of which reservoirs were composed of turbidite sand layers. In the view of resource explorations, methane hydrate concentrated zones are more attractive than other methane hydrate bearing zones because they can reserve much amount of methane hydrate locally. 　We developed an optimal interpretation workflow for delineation of methane hydrate concentrated zones. The workflow includes evaluation and integration of following four indicators: (A) BSR, (B) Turbidite sequence, (C) Strong seismic reflector and (D) relatively higher interval velocity. It enabled in the eastern Nankai Trough to extract more than 10 methane hydrate concentrated zones and evaluate their rock volume successfully. 11463 Resource Assessment of Methane Hydrate in the Eastern Nankai Trough, Japan 2008 Offshore Technology Conference 2008/5/7 Tetsuya Fujii, Tatsuo Saeki, Toshiaki Kobayashi, Takao Inamori, Masao Hayashi, Osamu Takano, Tokujiro Takayama, Tatsuji Kawasaki, Sadao Nagakubo, Masaru Nakamizu, Kenichi Yokoi (Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Resource assessment of methane hydrate (MH) in the Eastern Nankai Trough was conducted through probabilistic approach using 2D/3D seismic data and drilling survey data from METI exploratory test wells “Tokai-oki to Kumano-nada” We have extracted more than 10 prospective “MH concentrated zones” characterized by high resistivity in well log, strong seismic reflectors, seismic high velocity, and turbidite deposit delineated by sedimentary facies analysis. The amount of methane gas contained in MH bearing layers was calculated using volumetric method for each zone. Each parameter, such as gross rock volume (GRV), net-to-gross ratio (N/G), MH pore saturation (Sh), porosiry, cage occupancy, and volume ratio was given as probabilistic distribution for Monte Carlo simulation, considering the uncertainly of these evaluations. The GRV for each hydrate bearing zones was calculated from both strong seismic amplitude anomaly and velocity anomaly. Time-to-depth conversion was conducted using interval velocity derived from Seismic Vision While Drilling (SVWD). Risk factor was applied for the estimation of the GRV in 2D seismic area considering the uncertainly of seismic interpretation. The N/G was determined based on the relationship between LWD resistivity and grain size in zones with existing wells. Seismic ficies map created by sequence stratigraphic approach was also used for determination of the N/G in zone without well controls. Porosity was estimated using density log, together with calibration by core analysis. The Sh was estimated by the combination of density log and NMR log, together with the calibration by observed gas volume from onboard MH dissociation tests using Pressure Temperature Core Sampler (PTCS). The Sh in zone without well control was estimated using relationship between seismic P-wave internal velocity and Sh from NMR log at well location. Total amount of methane gas in place contained in MH within survey area in the eastern Nankai Trough was estimated to be 40 tcf as Pmean value. Total gas in place for MH concentrated zone was estimated to be 20 tcf (Half of total amount) as Pmean value. Sensitivity analysis indicated that the N/G and Sh have higher sensitivity than other parameters, and they are important for further detail analysis. 11446 Water, CO2-WAG and Flue Gas IOR/EOR Injection Pilot Studies in South Chicontepec Reservoirs, Mexico Second International Oil Congress and Exhibition in Mexico 2007/6/28-30 M. Abbaszadeh (IPS)、Kenji Ohno(Japan Oil, Gas and Metals National Corporation) Technology Research & Development Department ［Abstract］This paper presents results of water, CO2, CO2-WAG and flue gas injection simulation studies in sector models in the fields of south Chicontepec deposit complex. The paper first introduces a general methodology for integrated geostatistical reservoir characterization to construct fine-scale geocellular models of the reservoir, incorporating sources of data at different scales. Sector models for pilot injection studies are extracted from fine-scale geostatistical realizations, upscaled into coarse-grid simulation models and calibrated to production performance data to serve as reliable predictive tools for IOR/EOR recovery process scenarios. EOS analyses and slim-tube simulations are performed to evaluate MMP with CO2 of varying N2 impurity. Detailed studies of various CO2 injection scenarios investigate applicability and limitations of CO2-EOR, and provide information on conditions under which CO2-EOR could be beneficial. Continuous water and CO2 injection studies determine limiting values of injectivity and incremental oil recovery factors. WAG studies for mobility control determine optimum slug size and WAG ratio, considering limitations on CO2 availability and excessive CO2 gas breakthrough. Flue gas, as an alternative fluid injection, is considered for EOR recovery process and pressure maintenance. Simulated recovery data indicates that flue gas injection is inefficient compared to waterflood and CO2-WAG injections, and that CO2-WAG injections at high pressures outperform waterflooding. 11445 Physical modeling of overburden effects Geophysics Vol.72 2007/7 Mu Luo（JGI）,Mamoru Takanashi(Japan Oil, Gas and Metals National Corporation), Kazuo Nakayama, Teruya Esaka（JGI） Geology & Geophysics Research Division ［Abstract］Physical modeling of overburden effects 11442 RISER MOTION ESTIMATION OF OIL PRODUCTION SYSTEM FOR ULTRA DEEP WATER FIFTH CONFERENCE ON BLUFF BODY WAKES AND VORTEX=INDUCED VIBRATIONS 2007/12/12-15 Shunji Kato, Shotaro Uto, Sotaro Masanobu（National Maritime Research Institute）, Hideyuki Suzuki（Tokyo Univ.）, Hiroaki Hirayama, Koji Mochida(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］RISER MOTION ESTIMATION OF OIL PRODUCTION SYSTEM FOR ULTRA DEEP WATER 11440 Fusion of 3D seismic exploration and seafloor geochemical survey for methane hydrate exploration Exploration Geophysics, 2007,38,1-6 2008/1 Sadao ngakubo, Toshiaki Kobayashi, Tetsuya Fujii, Takao Inamori(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］The MH21 Research Consortium has conducted a high-resolution 3D seismic survey and a seafloor geochemical survey, to explore methane hydrate reservoirs in the eastern Nankai Trough, offshore Japan. Excellent geological information about shallow formations was obtained from the high-resolution 3D seismic survey, which was designed to image the shallow formations where methane hydrates exist. The information is useful in constructing a geological and geochemical model, and especially to understand the complex geology of seafloor, including geochemical manifestations and the structure of migration conduits for methane gas or methane-bearing fluid. 　By comparing methane seep sites observed by submersibles with seismic sections, some significant relationships between methane hydrate reservoirs, free gas accumulations below he seafloor, and seafloor manifestations are recognised. Bathymetric charts and seafloor reflection amplitude maps, constructed from seismic reflections from the seafloor, are also useful in understanding the relationships over a vast area. A new geochemical seafloor survey targeted by these maps is required. 　The relationships between methane hydrate reservoirs and seafloor manifestations are becoming clearer from interpretation of high-resolution 3D seismic data. The MH21 Research Consortium will continue to conduct seafloor geochemical surveys based on the geological and geochemical model constructed from high-resolution 3D seismic data analysis. 　In this paper, we introduce a basis for exploration of methane hydrate reservoirs in Japan by fusion of 3D seismic exploration and seafloor geochemical surveys. 11439 A Mathematical Model for the Formation and Dissociation of Methane Hydrates in the Marine Environment Journal of Geophysical Research, Vol.113, B01201 2008/1/12 Sabodh K. Garg, J. W. Prichett（Science Applications International Corporation), Arata Katoh（JGI), Kei Baba（JAPEX）, Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］A Mathematical Model for the Formation and Dissociation of Methane Hydrates in the Marine Environment 11436 Introduction of the 2007-2008 JOGMEC/NRCan/Aurora Mallik Gas Hydrate Production Research Program, NWT, Canada 2007 AGU Fall Meeting 2007/12/10-14 Koji Yamamoto, Masaaki Numasawa, Masato Yasuda, Kasumi Fujii, Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation), Scott R Dallimore, J. Fred Wright, F. Mark Nixon (NRCan) Methane Hydrate Research Project Team ［Abstract］Introduction of the 2007-2008 JOGMEC/NRCan/Aurora Mallik Gas Hydrate Production Research Program, NWT, Canada 11434 Research and Development Studies of the Mallik Gas Hydrate Deposit, Mackenzie Delta Geological Association of Canada Annual Meeting 2007/5/23-25 Scott R. Dallimore（NRCan）, Kenichi Yokoi, Yutaka Imasato(Japan Oil, Gas and Metals National Corporation), A.Applejohn(Aurora Research Institute) Methane Hydrate Research Project Team ［Abstract］Research and Development Studies of the Mallik Gas HydrateDeposit, Mackenzie Delta 11431 Core Velocity Measurements of Oil Sands for Quantitative Interpretation of Seismic 3D Seismic Steam Front Monitoring. SEG Development & Production Forum "Heavy Oils" 2007/7/31 Shigenobu Onozuka, Ayato Kato(Japan Oil, Gas and Metals National Corporation), Toru Nakayama （JAPEX）, Ray E. Nasen（JACOS) Geology & Geophysics Research Division ［Abstract］Core Velocity Measurements of Oil Sands for Quantitative Interpretation of Seismic 3D Seismic Steam Front Monitoring. 11416 Application of Oil-Water Kr/Pc Upscaling Methodology Based on Pore-Type Ratios 2007 International Symposium of the Society of Core Analysts 2007/9/12 Kazuhito Oseto, Osamu Himeno, Makoto Watanabe, Toshinori Nakashima(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］Our methodology provides fast and robust computation of upscaling by introducing a new averaging technique as a part of the capillary limit method, that is basically suited to giant, heterogeneous and oil wet reservoirs. In our past studies, its effectiveness was verified at core scale upscaling, i.e. pore scale to core scale, as well as reservoir simulation scale upscaling, i.e. fine model to coarse model. This paper introduces a practical approach for upscaling which bridges the various scales. In this study, the reservoir rock from a giant carbonate reservoir in the Middle East was characterized as the aggregate of three Pore-Types. The representative Kr/Pc curves for each Pore-Type were derived from core flood simulation as a result of matching with water-oil displacement tests. Then, Pore-Type Ratio, i.e. the population ratio of each Pore-Type, was quantified by the geological observation of the core slabs for the whole interval of the reservoir. Based on the Pore Type Ratios, Kr/Pc curves were upscaled to the simulation grid scale using an in-house software called CAVLUP. The simulation results showed that the Pore Type Ratio model reasonably reproduced water cut performances without any history matching manipulations. As a result, applied methodology in this study demonstrated its effectiveness to upscale pore scale data to reservoir simulation scale. This advantage is suited especially to the upscaling of big and heterogeneous geological models. 11415 Comprehensive Approach of Core Analysis to Predict Waterflooding Performance in a Heterogeneous Carbonate Reservoir International Energy Agency Collaborative Project on Enhanced Oil recovery 2007/9/7 Kazuhito Oseto, Komei Okatsu(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］The field of interest is a heterogeneous carbonate reservoir, offshore Abu Dhabi. A pore system in the field is classified into three categories based on the pore throat size, i.e. Macropore, Mesopore and Micropore. Such pore size variation is a key parameter that controls oil/water displacement, especially when imbibition/drainage processes can frequently take place in a reservoir in conjunction with subsequent wettability alteration. This study deeply evaluates the cross-correlation between the pore system, imbibition/drainage processes, wettability alteration and oil recovery by integrative core analyses. Two core waterflooding tests were conducted under different wettability conditions, i.e. water wet and oil wet. The oil recoveries were both high while there were some differences in Swir. These similarity and differences can be explained by different controls with different pore size in the proposed pore system. 11413 Detailed analysis of methane hydrate concentrated zone of lobe type 2007 AGU Fall Meeting 2007/12/11 Toshiaki Kobayashi, Tatsuo Saeki, Takao Inamori, Tetsuya Fujii, Naoyuki Shimoda(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Japan Oil, Gas and Metals National Corporation (hereinafter called JOGMEC), as a member of MH21 Research Consortium, takes charge of a study of the Research for Resources Assessment, and is pursuing a possibility that methane hydrate, which is presumed to be distributed around ocean area of Japan, will be energy resources. JOGMEC is currently conducting analysis of seismic data which was acquired by 3D seismic survey conducted from Tokai-Oki to kumano-nada in the eastern Nankai Trough by METI (Ministry of Economy, Trade and Industry )in 2002 under the national program of assessment for methane hydrates as energy resources. It was understood that methane hydrate was correlated to high resistivity and high velocity based on the results of drilling surveys and velocity analysis, and that methane hydrate concentrated zones can be roughly classified into the channel type and lobe type by seismic geomorphology because they were characterized with reserves consisting turbidite sand bodies. In this study, the detailed analysis of the inner structure of the methane hydrate concentrated zone of lobe type was conducted to understand the occurrence configurations of methane hydrates. The reflected waves that construct the methane hydrate concentrated zones in the seismic data were extracted and those reflected waves were classified into some groups every one reflector. As the result, some reflectors that construct the methane hydrate concentrated zones were revealed. Those reflectors show the layers including methane hydrates, and the detailed distribution of the methane hydrates in those layers was revealed by the intensity distribution of the amplitude. This time, we introduce the example of the detailed analysis of the methane hydrate concentrated zone in the lobe of submarine fan. 11412 Methane Hydrate reservoir model around the Eastern Nankai Trough area affshore Japan 2007 AGU Fall Meeting 2007/12/10-14 Takao Inamori, Masao Hayashi, Toshiaki Kobayashi, Naoyuki Shimoda, Osamu Takano, Tokujiro Takayama, Tetsuya Fujii, Sadao Nagakubo, Tatsuo Saeki(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］The Research Consortium for Methane Hydrate Resources in Japan (hereafter the MH21 Research Consortium) was established to undertake research in accordance with Japan's Methane Hydrate Exploitation Program. In 1996 and 2001, 2D seismic surveys were conducted and delineated the BSR distribution. The 3D seismic survey was conducted in this area in 2002. Bottom Simulating reflectors (BSRs) were widely found on the marine seismic data acquired in the shelf-slope in the Eastern Nankai Trough area. BSRs indicate the existence of methane hydrates. However, we cannot estimate detail reservoir information from distribution of BSRs. The gas hydrate-bearing sediments are heterogeneous and complex both vertically and horizontally, because methane hydrate-bearing layers are mainly turbidite sands - channel-levee or lobe sediments. The occurrence of methane hydrates was first confirmed by corings and borehole logging data around the Eastern Nankai Trough offshore Japan in 2000. METI conducted two drilling campaigns around the eastern Nankai Trough area. Total 38 boreholes were drilled, and recorded many logging data by wireline or LWD. We separate three types of methane hydrate reservoir among methane hydrate-bearing zone from reviewing the well logging data mainly the resistivity and P or S wave velocity. One is low saturation-type, the other is uncontinuous high saturation-type, the last is the continuous high saturation-type, and also we call the methane hydrate-concentrated zone as this type. If we will explore and exploit the methane hydrate, our main target is the continuous high saturation-type, as the methane hydrate-concentrated zone. We delineated the methane hydrate reservoir by the picking the reflector as the methane hydrate sub reservoir body for the turbidite channel-levee or lobe system around the eastern Nankai Trough area. On the other hand, we received the P or S wave velocity and the methane hydrate saturation at the wells in the methane hydrate-concentrated zone. We estimated the matrix-support or pore-filling model from the relationship between the P or S wave velocity and the methane hydrate saturation. 11411 Extraction of methane hydrate concentrated zone in the eastern Nankai Trough 2007 AGU Fall Meeting 2007/12/10-14 Tatsuo Saeki, Tetsuya Fujii, Takao Inamori, Toshiaki Kobayashi, Masao Hayashi, Sadao Nagakubo, Osamu Takano(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Methane hydrate, a solid compound formed from methane and water, occurs naturally in permafrost regions on-land and in deep continental slopes offshore and has been examined as future energy resources. The existence of methane hydrate in the eastern Nankai Trough region, offshore Japan, was confirmed by drilling the MITI well "Nankai Trough" in 1999. Aiming commercialization of methane hydrate production, the Research Consortium for Methane Hydrate Resources in Japan (MH21) has been executing geological and geophysical surveys around the eastern Nankai Trough since 2001 as a nation project. Interpretation and analysis studies based on 2D/3D reflection seismic surveys, multi-wells drilling campaign and other geological surveys revealed existence of methane hydrate concentrated zones, of which reserves were constructed with turbidite sand layers. In the view of resource explorations, methane hydrate concentrated zones are more attractive than other methane hydrate bearing zones because they can save much amount of methane hydrate locally. We developed the geological interpretation workflow optimized for delineation of methane hydrate concentrated zones. The workflow consists of following 4 factors: (1) BSR interpretation, (2) Delineation of turbidite sand bodies, (3) Detection of Strong seismic reflectors suggesting methane hydrate concentrated sand layers, and (4) high density velocity analysis. It enabled in the eastern Nankai Trough to extract methane hydrate concentrated zones and evaluate their rock volume successfully. 11410 Origin and Migration of Gas in Gas Hydrate-bearing Sediments In the eastern Nankai Trough, Japan 2007 AGU Fall Meeting 2007/12/10-14 Amane Waseda(JAPEX), Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Origin and Migration of Gas in Gas Hydrate-bearing Sediments In the eastern Nankai Trough, Japan 11409 Relation between methane hydrate -bearing formations and geological phenomena on the seafloor In the eastern Nankai Trough, Japan 2007 AGU Fall Meeting 2007/12/10-14 Sadao ngakubo, Toshiaki Kpbayashi, Takao Inamori, Tatsuo Saeki, Naoyuki Shimoda, Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation), Sumito Morita, Manabu Tanahashi(AIST) Methane Hydrate Research Project Team ［Abstract］In 2002, a series of high-resolution 3D seismic surveys was conducted in the Tokai-Oki, the Daini-Atsumi Knoll, the Kumano-nada In the eastern Nankai Trough, Japan. Research Consortium for Methane Hydrate Resources in Japan(MH21) conducted resource assessment of methane hydrate In the eastern Nankai Trough by various seismic data analyses combining results of the exploratory wells conducted in 2005. By these analyses, occurrence of methane hydrate In the eastern Nankai Trough is coming to light. The MH21 has also interpreted the relation between methane hydrate-bearing formations and various geological phenomena on the seafloor, such as pockmarks and carbonate outcrops, using the 3D seismic data in the three survey areas. Bathymetric maps and seafloor amplitude maps constructed by the high-resolution 3D data provided lots of information on the seafloor. Some areas show very high intensity on the seafloor amplitude maps. It is expected that the areas showing strong amplitude correspond to the distribution of carbonate outcrops which are likely precipitated by methane seep activities. By checking the seafloor amplitude maps, seismic sections and methane seep sites observed by the previous submersible dives, some significant correlations are recognized between methane hydrate-bearing formations and various phenomena on the seafloor. It may be likely that the occurrence of methane hydrate and the geological phenomena on the seafloor have a strong implication with some typical geologic structures, e.g. shallow fault, highly-permeable sediments and hydraulic fractures, which may control the fluid migration. Besides, in this study we learnt that bathymetric map and seafloor amplitude map constructed by the high-resolution 3D seismic data are very useful not only for interpretation of relation between methane hydrate-bearing formation and various phenomena on the seafloor but also for designing the following seafloor investigations. This study is conducted by the MH21. 11408 The particle size effect on Gas hydrate Formation in powdered silica particles 2007 AGU Fall Meeting 2007/12/10-14 Tatsuji Kawasaki(Japan Oil, Gas and Metals National Corporation), Hailong Lu, John A.Ripmeester, Huang Zeng(National Research Council Canada), Tetsuya Fujii, Masaru Nakamizu(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Based on the investigations in the past years, it has been recognized that methane hydrates in Nankai Trough primarily occur in turbidite sediments (Fujii et al. 2005; Uchida et al., 2005). Turbidite is composed of a set of sediments, generally becoming finer upward in particle size, from coarse sand to clay (Bouma, 1962). In natural environment the formation of methane hydrate will be inevitably subject to the influence of sediments, so the modes of gas hydrate formation and occurrence might be different in the sediments with various particle sizes and mineral compositions. The elucidation of this issue, how sediments affect methane hydrate formation and occurrence will help in efficient hydrate exploration, accurate estimation of hydrate reserve, and the design of hydrate production method. In this research, we especially studied the particle size effect on the water conversion degree to hydrate using a set of powdered silica particles with the size from medium silt (<20 μm) to medium sand (250-500 μm). The test specimens were saturated with 3.5% NaCl solution, simulating the interstitial water of marine sediments, and reacted with methane gas at the pressure of 〜 10 MPa and temperature of 3 ℃. The water conversion degree to hydrate in a test specimen was estimated with the amount of gas that was clathrated in hydrate. The obtained results indicate a clear relationship between water conversion degree to hydrate and particle size: only 3.2% when particle size is <20μm, increasing dramatically from 5.7% to 82.8% when particle size changes from 〜30μm(coarse silt ) to 〜200μm(fine sand), and almost stable at 〜80% when particle size is > 250μm (medium sand). Because the test materials are all silica, the difference in water conversion degree to hydrate should be resulted from physical properties of silica particle, specific surface area, and/or the property confined by silica particle, pore size. This study was carried out as a part of Research Consortium for Methane Hydrate Resources in Japan(MH21). 11407 Resource Assessment of Methane Hydrate In the eastern Nankai Trough, Japan 2007 AGU Fall Meeting 2007/12/10-14 Tetsuya Fujii, Tatsuo Saeki, Toshiaki Kobayashi, Takao Inamori, Masao Hayashi, Osamu Takano(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Resource assessment of methane hydrate(MH) in the eastern Nankai Trough was conducted through probabilistic approach using 2D/3D seismic survey data and drilling survey data from METI exploratory test wells "Tokai-oki to Kumano-nada"[1,2,3]. We have extracted several prospective "MH concentrated layers (structures)" [4] characterized by high resistivity in well log, seismic high amplitude, seismic high velocity, and turbidite deposit by sedimentary facies analysis. The amount of methane gas derived from MH bearing layers were calculated using volumetric method for each structure. Each parameter, such as Gross Rock Volume (GRV), net-to-gross ratio (N/G), MH pore saturation (Sh), porosity, cage occupancy, and volume ratio was given as probabilistic distributions for Monte Carlo simulation considering the uncertainly of these value. GRV for each hydrate bearing structures was calculated from both strong seismic amplitude anomaly and velocity anomaly. Time-to depth conversion was conducted using interval velocity derived from SVWD (Seismic Vision While Drilling). Risk factor was applied for the estimation of GVR in 2D seismic area considering the uncertainty of seismic interpretation. N/G was determined based on the relationship between LWD resistivity and grain size in the structure with existing wells. 3 ohm-m was used for the typical cut off value for the net intervals. Seismic facies map created by sequence stratigraphic approach [5] was also used for the determination of N/G in the structure without well controls. Porosity was estimated using density log, together with the calibration by core analysis. Sh was estimated by combination of density log and NMR log (DMR method), together with the calibration using observed gas volume from onboard hydrate dissociation tests of PTCS (Pressure Temperature Core Sampler) [6]. Sh in the structure without well control was estimated using relationship between P-wave interval velocity and Sh from NMR log at well location. Cage occupancy was determined to be around 0.95 by refereeing recent field observations. Constant value of 172 in standard condition was used for volume ratio. Total amount of methane gas in place contained in MH in the eastern Nankai Trough within survey area was estimated to be 40 tcf as Pmean value (10 tcf as P90 value, 82 tcf as P10 value). Total gas in place for MH concentrated layer was estimated to be 20 tcf (Half of total amount) as Pmean value. Sensitivity analysis indicated that sensitivity of N/G and Sh is higher than other parameters, and important for further detail analysis. [1] Takahashi et al. (2005): Proc. of 2005 OTC, 2-5 May, Houston, Texas, U.S.A.. [2] Fujii et al. (2005): Proc. of 5th ICGH, Trondheim, Norway, 974-979. [3] Tsuji et al. (2007): AAPG Special Publication (in press) [4] Saeki et al. (2007): Abst. of 2007 Technical Meeting of the JAPT, June 5-7, 2007, Tokyo, p49. [5] Takano et al. (2007): Abst. of 2007 Technical Meeting of the JAPT, June 5-7, 2007, Tokyo, p34. [6] Fujii et al. (2007): AAPG Special Publication (in Press). 11406 Turbidite channel as methane hydrate concentrated zone - study results of 3D seismic data interpretation - 2007 AGU Fall Meeting 2007/12/10-14 Naoyuki Shimoda, Tatsuo Saeki, Takao Inamori, Toshiaki Kobayashi, Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］3D seismic data were acquired In the eastern Nankai Trough area, offshore Japan by METI in 2002 in order to evaluate resource potential of methane hydrates. Through the studies on these seismic data and the results of multi-well drilling surveys carried out in 2004, more than 10 methane hydrate concentrated zones were delineated in this area. The methane hydrate concentrated zones were characterized by turbidite sand bodies which can be roughly classified into channels and lobes in the seismic geomorphology point of view. We focused our attempt to reveal internal structure of a channel type methane hydrate concentrated zone using high resolution 3D seismic data. Basically, channel complex can be recognized by reflectors suggesting erosion surfaces and internal bodies of sand layers. The whole channel is vertically divided to the upper and lower parts bounded by BSR. As it is difficult to interpret the internal structure in the lower part due to the less continuous reflectors, only the upper part was geomorphologically analyzed by picking the high amplitude reflectors which suggest the hydrate concentrated sand dominated bodies. The group of the picked reflectors suggests the 3D feature of the channel development. The channel was bended during its sediment deposition. The original channel flowed from northeast to south. And later, the flow was from northeast to west-southwest. Thus, we can find the detailed shape of each sand dominated body within channel, and therefore, it is expected that detailed analysis of many reflector patches in the channel can teach us the properties of methane hydrate bearing thin sand dominated bodies by classifying their shapes. Further, such properties will contribute to the future precise volume estimation of methane hydrates, and also to the model construction for production simulation. This study is carried out for Research Consortium for Methane Hydrate Resources in Japan (MH21). 11405 Numerical Simulation of Generation and Migration of Methane and Accumulation of Methane Hydrate In the eastern Nankai Trough 2007 AGU Fall Meeting 2007/12/10-14 Ryosuke Aoyagi(Mizuho Information and Research Institute), Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation), Minoru Yoshikawa, Yutaka Nakama(Mizuho Information and Research Institute), Tatsuji Kawasaki, Sadao Nagakubo, Tokujiro Takayama, Toshiaki Kobayashi, Takao Inamori, Masaru Nakamizu(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］We have developed 2-D numerical simulator "SIGMA-MH" for methane hydrate(MH) accumulation in order to simulate geological/physicochemical phenomena related to MH deposits formation in deepwater sediment and to clarify controlling factors for MH accumulation. SIGMA-MH is a modified version of "SIGMA-2D", basin simulator for petroleum system developed by JOGMEC. SIGMA-MH has models such as microbial methane generation model and MH formation/dissociation model, with which MH accumulation can be simulated. An empirical model is used for microbial methane generation model. In this model, maximum gas generation rate is estimated from organic accumulation rate, which are derived from ODP gas sample analysis. Kinetic reaction model is applied for MH formation/dissociation. MH formation/dissociation rate is expressed as a function of the difference between the fugacity of methane at gas phase and fugacity of methane at the three-phase equilibrium for MH-water-methane gas. Using SIGMA-MH, case studies were conducted for two sections including boreholes at Tokai-Oki and Daini-Atsumi area where MH concentration is detected. Geological structure used in the simulation was estimated by seismic survey. Rock facies were determined by logging and core sample. Heat flow was calibrated by present temperature measured by geothermometer. Base case, shallow case, and deep case were conducted as a sensitivity analysis for paleo-water depth. As a result, a series of recycling process, that is, methane gas generation, MH formation, MH dissociation, gas migration, and MH formation, was simulated. MH accumulation estimated by simulation nearly corresponds to that of actual borehole. The phenomena that methane gas migrates through permeable sand layers and MH accumulates in them suggests that permeability are a key of MH accumulation. It was found that paleo-water depth plays an important role because it affects on present MH accumulation. For future work, we will conduct sensitivity analyses of quantitative parameters and paleo-water depth and improve SIGMA-MH as a tool for understanding controlling factors of MH accumulation. This study was carried out as a apart of Research Consortium for Methane Hydrate Research in Japan(MH21). 11404 The Stabilization of Methane Hydrate by Pressurization with He or N2 Gas The Journal of Physical Chemistry 2007/12 Hailong Lu（National Research Council Canada）, Yoshihiro Tsuji(Japan Oil, Gas and Metals National Corporation), John A. Ripmeester(National Research Council Canada) Geology & Geophysics Research Division ［Abstract］The behavior of methane hydrate was investigated after it was pressurized with helium or nitrogen gas in a test system by monitoring the gas compositions. The results obtained indicate that even when the partial pressure of methane gas in such a system is lower than the equilibrium pressure at a certain temperature, the dissociation rate of methane hydrate is greatly depressed by pressurization with helium or nitrogen gas. This phenomenon is only observed when the total pressure of methane and helium (or nitrogen) gas in the system is greater than the equilibrium pressure required to stabilize methane hydrate with just methane gas. The following model has been proposed to explain the observed phenomenon: (1) Gas bubbles develop at the hydrate surface during hydrate dissociation, and there is a pressure balance between the methane gas inside the gas bubbles and the external pressurizing gas (methane and helium or nitrogen), as transmitted through the water film; as a result the methane gas in the gas bubbles stabilizes the hydrate surface covered with bubbles when the total gas pressure is greater than the equilibrium pressure of the methane hydrate at that temperature; this situation persists until the gas in the bubbles becomes sufficiently dilute in methane or until the surface becomes bubble-free. (2) In case of direct contact of methane hydrate with water, the water surrounding the hydrate is supersaturated with methane released upon hydrate dissociation; consequently, methane hydrate is stabilized when the hydrostatic pressure is above the equilibrium pressure of methane hydrate at a certain temperature, again until the dissolved gas at the surface becomes sufficiently dilute in methane. In essence, the phenomenon is due to the presence of a nonequilibrium state where there is a chemical potential gradient from the solid hydrate particles to the bulk solution that exists as long as solid hydrate remains. 11403 Development and experimental feasibility study of the prediction method for hot corrosion of gas turbine components International Gas Turbine Congress 2007 Tokyo 2007/12/2 Hironori Kamoshida, Hideki Tamaki, Yoshitaka Kojima（Hitachi Research Lab.,Hitachi,Ltd.,), Tomoko Watanabe(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］Development and experimental feasibility study of the prediction method for hot corrosion of gas turbine components 11401 Pore space reconstruction of vuggy carbonates using microtomography and multiple-point statistics Water Resources Research Vol.43 2007/11/29 Hiroshi Okabe(Japan Oil, Gas and Metals National Corporation/Imperial College London), Martin J. Blunt(Imperial College London) Petroleum Engineering Research Division ［Abstract］To reconstruct complex porous media, such as carbonates, we propose a two-step approach to combine different types of images: microtomography at the resolution of a few microns to resolve large pores and vugs, with statistically reconstructed high-resolution images for smaller features. Two-dimensional (2-D) thin sections provide multiple-point statistics which describe the statistical relation between multiple spatial locations that can be used to generate 3-D images with accurate connectivity. These statistical reconstructions are combined with images directly measured by microtomography. The integrated method is tested on carbonates for which 3-D images of disconnected vugs are captured, while 2-D thin sections characterize the small-scale structure. The integrated images have permeabilities computed using the lattice Boltzmann method that are similar to laboratory-measured values. 11400 A Wave Propagation-based Method for Improved Seismic Fracture Prediction ASEG (Australian Society of Exploration Geophysicists) 2007/11/21 Mu Luo（JGI, Ink.）, Mamoru Takanashi(Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Division ［Abstract］Using physical model data, this study first physically confirms the significance of P-wave overburden effect, and most importantly, tests the wave-propagation based concept in developing our methodology to study fracture/anisotropy. The 70 m width of fractures in our model, comparing with a minimum offset of 600 m, was produced for conducting fracture study or clarify the observed anisotropy signatures (amplitude and velocity) originated from the fractured model. The model itself, comparing with the wavelength, is optimized for evaluating the fracture and the heterogeneous overburden effect. The vertical fractures contained in the model may be viewed as simplified fracture zone of randomly dispatched fracture swaps or carbonate/channel with fractures and anomalous amplitude and velocity, while the strong source radiation could represent a poor field acquisition. Nevertheless, test results indicate that the new method could identify interval/location of fracture-related velocity slowdown and amplitude attenuation. This will highly contribute to correct interpretation and prevent from misinterpretation of the layer below anomaly, which can be also helpful in the field examples. Another important indication is that the velocity anisotropy, normally considered higher along the fractures than perpendicular to the fractures, could not be true due to overburden heterogeneity. 11399 Application of prestack depth migration across the Ichthys field, Browse basin ASEG (Australian Society of Exploration Geophysicists) 2007/11/21 Masamichi Fujimoto(INPEX Browse Ltd.), Mamoru Takanashi(Japan Oil, Gas and Metals National Corporation), Mike Szczepaniak, Takeshi Yoshida(INPEX Browse Ltd.) Research Project Team on Subsurface Technologies for Field Development ［Abstract］This study aimed to reduce uncertainty of reservoirs’ depth and improve image quality in the Ichthys field, Browse Basin. The following method, detailed tomographic velocity modelling combined with prestack depth migration (PSDM), isotropic Kirchhoff PSDM and the well calibration were implemented. Initial stacking velocity analysis for 3D prestack time migration (PSTM) revealed geologically implausible and undulating RMS velocity patterns at reservoir depths across the main section of the field, which reduced image quality and reservoir depth accuracy. Further investigation with forward modelling revealed that the velocity distortions might be primarily induced by shallow Tertiary sequences, containing highly contrasting, narrow, elongate velocity anomalies. Layered/blocky modelling combined with dense residual moveout picking and 3D finite-offset tomography enabled the construction of a complex velocity model in the shallow section. Subsequent gridded/smoothed velocity tomography with constraints was then used for updating the entire velocity field. The final derived velocity field was more systematically correlated with that observed at the wells and the corresponding depth structure produced from PSDM appeared to contain less distortion and be more geologically realistic. The resultant velocity model is currently being incorporated into the structural evaluation for the Ichthys Field. 11398 Investigation of Overburden Heterogeneity Effects and Their Removal through High Resolution Tomography and Prestack Depth Migration ASEG (Australian Society of Exploration Geophysicists) 2007/11/21 Mamoru Takanashi(Japan Oil, Gas and Metals National Corporation), Dimitri Chagalov, Pierre Plasterie(CGGVeritas), Masamichi Fujimoto(INPEX Browse Ltd.) Research Project Team on Subsurface Technologies for Field Development ［Abstract］For contributing to precise depth delineation in the Ichthys giant gas field offshore northwest Australia, we investigated shallow velocity heterogeneity effects using forward modelling and seismic data review. We discovered that their removal through applications of high-resolution tomographic velocity modelling and prestack depth migration (PSDM) enabled correct representation of the target reservoir structure.　Analysis of synthetic seismic pre-stack gathers generated from forward modelling demonstrated that small velocity anomalies, such as channels, in shallow overburdens could give rise to apparent seismic RMS velocity artefacts at deeper target levels. Delineation of “true” velocity anomalies and implementation of PSDM using precise shallow velocity model were required for solving these problems. In accordance with the phenomenon predicted by forward modelling, examination of coinciding patterns of time-thickness, amplitude and deep prestack time migration (PSTM) velocity allowed determination of the shallow heterogeneous layers that caused target velocity undulation.　We employed two iterations of tomographic velocity model updating for PSDM velocity model building. First, the shallow heterogeneous velocity patterns were successfully identified by utilising the dense residual moveout picking and the layer-based 3D high-resolution finite-offset tomography. Subsequent grid-based global tomography with constraints was used for updating the entire velocity field and delivered stable velocity pattern at the deep. This two-step approach successfully eliminated deep velocity artefacts. 11396 A Japanese perspective on the use of new technologies Windsor Energy Group Houston Meeting 2007/11/6 Yoshihiro Tsuj(Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Division ［Abstract］The importance of new technology in Exploration and Production to extend the reserves and high production rate is recognized. Therefore, associated with the recently published 'Japan's New National Energy Strategy' by the Ministry of Economy, Trade and Industry (METI), Technology and Research Center (TRC) of Japan Oil, Gas and Metals National Corporation (JOGMEC) has estimated the medium to long term R&D strategy toward 2030. In order to identify the goals to be reached by 2030 in individual prioritized technological fields, "10 Core Projects" were proposed. Those are related to (1) EOR to have 70% oil recovery, (2) Reservoir total visualization for the accuracy of reserves assessment in exploration and development, (3) Offshore oil field development to the depth of 3000m, (4) Well drilling to increase the drilling and completion efficiency, (5) Next-generation advanced resource development to find out technological breakthrough through incorporating leading-edge technologies such as IT, robotics, nanotechnology and biotechnology, (6) National methane hydrate project from exploration to development of methane hydrate, (7) Ultra heavy oil by incorporating upgrading and other technologies into oil-field development upstream technologies, (8) Next-generation Non-conventional Hydrocarbon Exploitation to develop enhanced coal bed methane (ECBM) technology and other next-generation technologies after the SAGD process, (9) GTL using the Japanese GTL process utilizing CO2 effectively, and (10) Next-generation oil and gas effective utilization by establishing new natural-gas transportation technology. To make the goals of the projects fruitful, JOGMEC-TRC recognizes that training of the participating engineers and geoscientists within the project,　cooperation and collaboration with Universities,　National Oil Countries,　Technological consultants,　other R&D institutes,　oil companies, and utilizing the field demonstration are very important, and it is committed to the technological advancement in the world of petroleum exploitation. 11392 DIRECT SYNTHESIS OF PROPANE/BUTANE FROM SYNGAS LP Gas Global Technology Conference 2006 2007/10/19-20 Kaoru Fujimoto(Tha University of Kitakyushu) Research Project Team on Emerging Gas Technologies ［Abstract］DIRECT SYNTHESIS OF PROPANE/BUTANE FROM SYNGAS 11390 Mitigation of Asphaltene Deposition Problems SPE Applied Technology Workshop(ATW) "Second Stage Field Development" 2007/10/17 Hideharu Yonebayashi(Japan Oil, Gas and Metals National Corporation) Research Project Team on Subsurface Technologies for Field Development ［Abstract］Mitigation of Asphaltene Deposition Problems 11389 Methane Hydrate Exploration around the eastern Nankai Trough The 37th Annual Conference of the Underwater Mining Institute 2007/10/15-17 Tatsuo Saeki, Tetsuya Fujii, Masaru Nakamizu, Kenichi Yokoi(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Methane hydrate, a solid compound formed from methane and water, occurs naturally in permafrost regions on-land and in deep continental slopes offshore and has been examined as future energy resources. The existence of methane hydrate In the eastern Nankai Trough region, offshore Japan, was confirmed by drilling the MITI well “Nankai Trough” in 1999. Aiming commercialization of methane hydrate production, the Research Consortium for Methane Hydrate Resources in Japan (MH21, core associations: JOGMEC[*1], AIST[*2] and ENNA[*3]) under METI [*4] has been executing geological and geophysical surveys around the eastern Nankai Trough since 2001 as a nation project. 　*1: Japan Oil, Gas and Metals National Corporation 　*2: National Institute of Advanced Industrial Science and Technology 　*3: Engineering Advancement Association of Japan 　*4: Ministry of Economy, Trade and Industry, originally MITI Interpretation and analysis studies based on reflection seismic survey (2D:2001, 3D:2002), multi-wells drilling campaign (2004) and other geological surveys revealed existences of methane hydrate high concentrated zones, which are much attractive in the view of resource explorations. The concentrated zones are recognized in geological layers with porous sediments, which are turbidite sand layers in most cases. The JOGMEC Geology & Geophysics group and partners developed the geological interpretation workflow optimized for methane hydrate resource assessment including delineation of methane hydrate concentrated zones, and evaluated resource potential around the eastern Nankai Trough. In this presentation, we will introduce the outline of above surveys and interpretations. 11388 Multidisciplinary Approach to Solve Borehole Instability Problems in a Shale Formation SPE Applied Technology Workshop(ATW) "Second Stage Field Development" 2007/10/15 Hirofumi Okano, Daisuke Kuramoto, Koji Yamamoto(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］Wellbore failures occur, when stress on wellbore exceeds the rock strength. Shale is the major source of instability, because it has a complex nature which we cannot describe using linear elastic, isotopic and homogeneous models. In this paper, we clarified the characteristics such as chemical activity, anisotropy and fissured nature. In addition, 3D proelastic models were used to estimate failed regions. The results of the numerical simulations showed that the hole conditions cannot be improved with too much weight of drilling mud. 11387 Gas to Wire System (GTW) for Developing "Small Gas Fields" and Exploiting "Associated Gas" SPE Applied Technology Workshop(ATW) "Second Stage Field Development" 2007/10/15 Tomoko Watanabe, Hirofumi Okano, Daisuke Kuramoto(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］A Gas to Wire system (GTW) is proposed as a new development concept for marginal gas fields. The aim of this project is to commercialise small stranded gas fields with a reserve between 10 bcf and 1tcf. GTW adopts onsite power generation utilising produced gas and has high efficiency, because there is no need to transport the produced gas. JOGMEC, Hitachi, JGC Corporation, Toyohashi University of Technology, and Arabian Oil Company conducted the research on high efficiency, low cost and low emission GTW by applying Gas Turbine Combined Cycle System (GTCC). The project includes a feasibility study on associated gas from a Middle East offshore oil field. 11386 Geochemical Study of Microbial Methanogenesis and Gas Hydrate Formation International Conference on Gas Hydrate 2007/10/5 Amane Waseda(JAPEX), Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Geochemical Study of Microbial Methanogenesis and Gas Hydrate Formation 11379 High pressure air injection into light oil reservoirs: experimental study on artificial ignition International Energy Agency Collaborative Project on Enhanced Oil Recovery 2007/9/5 Takeshi Onishi(Japan Oil, Gas and Metals National Corporation), Katsumi Katoh（AIST）、Katsumo Takabayashi, Hiroshi Uematsu(Teikoku Oil Co.,Ltd.,), Komei Okatsu(Japan Oil, Gas and Metals National Corporation), Yuji Yada, Yuji Ogata(AIST) Petroleum Engineering Research Division ［Abstract］Recently, High Pressure Air Injection (HPAI) is considered to be an effective EOR method to light oil reservoirs. HPAI has some remarkable merits as follows. (1)Injection gas source can be supplied anywhere for free. (2)Initial cost is relatively inexpensive because the main facility required is only air compressor. (3)The method can be applied even in low permeable reservoirs where water cannot be injected. On the other hand, the evaluation of HPAI is difficult, because the mechanism and the reactions of oxidation and combustion are complicated. A Japanese domestic oil field has been investigated to apply HPAI as tertiary mode. Experimental and numerical simulation results suggest that it is possible to obtain the incremental oil recovery by HPAI. But they also suggest that the ignition temperature of the oil may be higher than the reservoir temperature. If ignition doesn’t occur in reservoir, thermal effect on recovery mechanism can not be expected and oxygen may be early breakthrough to producer because of low oxygen consumption. So, oxygen consumption is important not only for the efficiency of incremental oil recovery but also for safety operation. Ignition method has to be ensured for the application of HPAI to the oil field. Accelerating Rate Calorimeter (ARC) Tests are carried out to assess the influence of oxygen slug and linseed oil on ignition temperature. The experimental results suggest that in case of oxygen slug the ignition temperature decreases but doesn’t reach the reservoir temperature even if high concentration of oxygen is applied. They also suggest that the ignition temperature decreases to the reservoir temperature in case of high concentration of linseed oil. 11378 Wettability evaluation by big borehole MRI International Energy Agency Collaborative Project on Enhanced Oil Recovery 2007/9/5 Yasuyuki Mino, Kazuhito Oseto (Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］It is difficult to predict fluid flow through heterogeneous reservoir rocks such as carbonates without knowing detail distributions of petrophysical properties of the rocks. Among those properties the wettability is of particular importance, however, any methods currently do not provide its spatial distribution. Magnetic Resonance Imaging (MRI) is expected to provide such a wettability distribution rapidly comparing to the Amott and USBM methods. We use a medical MRI machine with a big borehole that can handle bigger samples and subsequently provides a whole picture of the core sample. However, there have been very few studies conducted to investigate the correlation between the MRI signals and the wettability using such big borehole machines while several researchers have used small borehole machines. In our study, the correlation between the T1 relaxation time and the wettability was investigated although further studies are necessary to obtain the wettability index in detail. 11377 Recent Activities of R&D Program on Methane Hydrates in Japan First International Energy Week & Exhibition and Symposium 2007/9/4-8 Koichi Sugiyama, Kenji Ohno(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］The exploratory test well "Nankai Trough" drilled in 2000 by MITI (Ministry of International Trade and Industry) offshore Japan confirmed, for the first time, methane hydrates in pore space of turbiditic reservoir sand like conventional gas resources. Japan's Methane Hydrate Exploration Program was issued on July 2001 envisaging a promotion of technical development for economical drilling, production and recovery of gas from methane hydrates, and a facilitation of its utilization for the long-term stable energy supply to Japan. The program shall define whether methane hydrates presumed to develop offshore Japan become the future energy resources for the country in accordance with the following framework of 16 years. Phase 1 (FY2001 to FY2008) Seismic survey, logging and coring. Onshore production tests in Canada. Phase 2 (FY2009 to FY2011) Offshore production tests. Phase 3 (FY2012 to FY2016) Study of economic feasibility, arrangements for commercial production and evaluation of environmental issues. Final report of the program will be submitted in the end of FY 2016. Research Consortium for Methane Hydrate Resources in Japan (MH21 Resources Consortium) has been established in March 2002. The consortium comprises of three leading organizations namely; Technology Research Center-Japan Oil, Gas and Metals National Corporation (JOGMEC-TRC), National Institute of Advanced Industrial Science and Technology (AIST) and Engineering Advancement Association of Japan (ENAA). The numbers of participants under the said Consortium are about 300 persons and about 30 organizations. The three leading organizations mentioned above represent the following working groups respectively to perform effectively R&D program in collaboration with MH21 Research Consortium Secretariat; 1. Research group of assessment of methane hydrates resources 2. Research group of production method and modeling 3. Research group of assessment of environment impact 11376 Pore-scale analysis of carbonates using 3D micro-CT imaging: effects of inclusion of microporosity IEA Collaborative Project on Enhanced Oil Recovery, 28th Annual Workshop and Symposium 2007/9/4-7 Hiroshi Okabe(Japan Oil, Gas and Metals National Corporation/Waseda Univ.), R. M.Sok, C.H.Arns(Australian National Univ.), M.A.Knackstedt(Australian Univ./University of New South Wales), T.J.Senden, A.P.Sheppard, H.Averdunk(Australian National Univ.), W.V.Pinczewski(Australian Univ./University of New South Wales) Research Project Team on Subsurface Technologies for Field Development ［Abstract］Carbonate reservoirs increasingly become important as they contain more than 50% of the world’s hydrocarbon reserves. Carbonate rocks are diverse and their pore space complex, therefore, they require detailed studies at the different level from micro to macro scale. Large variations in petrophysical properties of carbonates are caused by wide variations in pore type, shape and interconnectivity. Petrophysical properties are directly related to the amount and type of porosity, the dominant feature size and the interconnectivity of different porosity groups. While the properties strongly depend on pore-scale physics, accurately measuring these attributes requires the detail analysis of pore structure in 3D. We describe the imaging of carbonate core samples in 3D and calculate some of petrophysical properties such as drainage capillary pressure and resistivity directly on the images. Then we correlate the resultant petrophysical properties to the pore structure of the rock. Connectivities of pores are studied as the bioclastic core samples have significant proportions of both connected and disconnected (separate) macropores. It is shown that inclusion of larger pores associated with the smaller pores results in complete connectivity of the macroporous phase and the inclusion of microporosity has a dramatic effect on the petrophysical properties for the bioclastic sample. Three dimensional imaging and analysis of carbonate core material at the pore scale can provide a basis for more accurate petrophysical models, narrow the range of uncertainty in estimates of petrophysical properties and improve the quantification of the resource within carbonate reservoirs. 11374 Hydrogen production from dimethyl ether by steam reforming over copper alumina catalysts prepared by the sol-gel method EUROPACAT VIII 2007/8/30 Kaoru Takeishi（Shizuoka Univ.) Research Project Team on Emerging Gas Technologies ［Abstract］New catalysts for hydrogen production from dimethyl ether (DME) have been developed. Cu-Zn/Al2O3 catalysts prepared by a sol-gel method produced large quantities of H2 and CO2 with DME steam reforming at 300 ℃. The catalysts are more useful for hydrogen production than general DME steam reforming catalysts (mixed catalysts of DME hydrolysis catalysts and methanol steam reforming catalysts). γ-alumina sites for DME hydrolysis into methanol, and copper sites for methanol steam into H2 and CO2 coexist on the surfaces of the sol-gel catalysts, and the two reaction occur systematically, and the catalysts produce H2 effectively from DME. 11373 Time-lapse 3D Seismic monitoring in the JACOS oil sands development field in Canada SEG Development & Production Forum "Heavy Oils" 2007/8/1 Toru Nakayama, Akihisa Takahashi(JAPEX), Ray Nasen(JACOS), Ayato Kato(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Division ［Abstract］Time-lapse 3D seismic study was conducted in the Japan Canada Oil Sands Limited (JACOS) Hangingstone steam-assisted gravity drainage (SAGD) operation area, Alberta, Canada. The time-lapse surveys were acquired in February, 2002 and in March, 2006. The two seismic volumes show distinct seismic response changes around the SAGD well pairs. From our time-lapse data analysis, these differences of the seismic responses were interpreted as phenomena caused by P-wave velocity decrease of the oil sands layers due to the steam-injection. 11372 Core velocity measurements of oil sands for quantitative interpretation of time-lapse 3D seismic steam front monitoring SEG Development & Production Forum "Heavy Oils" 2007/7/31 Shigenobu Onozuka, Ayato Kato(Japan Oil, Gas and Metals National Corporation), Toru Nakayama(JAPEX), Ray Nasen（JACOS) Petroleum Engineering Research Division ［Abstract］ The time-lapse seismic survey was conducted in the JACOS Hangingstone SAGD operation area. The preliminary result of the survey shows significant difference of seismic response between the baseline and repeat surveys. The difference is interpreted as effect of steam injection. It is, however, not well understood how the seismic amplitude and velocity changes of the oil sands due to the variations of reservoir pressure, temperature and fluid saturation expected during the steam injection in this field. JOGMEC hence developed a novel apparatus for measuring ultrasonic core velocities of unconsolidated sample like the oil sands. We measured and analyzed P-and S-velocities of plug samples of the oil sands acquired from the field, as well as bitumen itself. We showed that behavior of bitumen strongly depends on temperature. In the temperature less than around 40C, bitumen works as like pseudo-solid, which cause several phenomena including high viscosity, low elasticity, substantial shear modulus, high attenuation and strong velocity dispersion. The core velocity measurements showed that natural logarithm function can be applied as a fitting curve for the relationship between the velocity and effective pressure, while two linear lines can be applied as a fitting curve for the relationship between velocity and temperature. In higher temperature than 80C, Gassmann equation can be applied for predicting velocity changes. From the velocity measurements and Gassmann equation analysis, we finally proposed the velocity model which can predict velocity changes of the oil sands caused by any variations of the reservoir conditions. Based on the velocity model, synthetic seismic traces at several reservoir conditions were calculated and compared to the actual seismic trace data at the well location. Seismic attenuation of the oil sands strongly depends on temperature, as well as bitumen. The attenuation information (Q value) may be able to be utilized for distinguishing area where oil sands reservoir is moderately heated (40<T<120C). We are working on quantitative interpretation integrating this study's results with the surface seismic data analysis. 11371 Direct Synthesis of Dimethyl Ether from Synthesis Gas Containing Oxygen 9th International Symposium on Biotechnology Metal Complexes and Catalysis 2007/7/28 Kaoru Takeishi（Shizuoka Univ.) Research Project Team on Emerging Gas Technologies ［Abstract］ I have developed the appropriate and excellent catalyst for DME direct synthesis. The catalysts, Cu-Zn/Al2O3 catalysts prepared by the sol-gel method, produce DME with high activity and high selectivity under the mild reaction temperature and pressure, even if the reaction gases contain some oxygen. 11365 Hydrogen Production from Dimethyl Ether by Copper Alumina Catalysts Prepared by Sol-Gel Method The 2nd International Conference on Advances in Petrochemicals and Polymers (ICAPP2007) 2007/6/26 Kaoru Takeishi（Shizuoka Univ.) Research Project Team on Emerging Gas Technologies Dimethyl ether (DME) is expected as a clean fuel of the next generation. I have developed new catalysts for hydrogen production by steam reforming of DME. Cu-Zn/Al2O3 catalysts prepared by a sol-gel method produce large quantities of H2 and CO2 by DME steam reforming under lower reaction temperature. H2 production by steam reforming of DME consists of two reaction steps. The first reaction is hydrolysis of DME into methanol. The second reaction is steam reforming of methanol that produces H2 and CO2. For this reason, the mixed catalysts of DME hydrolysis catalysts and methanol steam reforming catalysts are used for hydrogen production by DME steam reforming. However, the copper alumina catalysts prepared by the sol-gel method in single use are more excellent for H2 production by DME steam reforming than the mixed catalysts. The reason is that -Al2O3 sites for DME hydrolysis and Cu sites for methanol steam reforming are co-existing closely on the catalyst surface. The consecutive reactions smoothly occur, and hydrogen is produced more effectively over the sol-gel Cu/Al2O3 catalyst in single use than over the mixed catalysts. Addition of Zn, Mn, or Fe into Cu/Al2O3 catalyst activates steam reforming of DME. The Cu-Zn(29-1wt.%)/Al2O3 catalyst showed the excellent activity of DME steam reforming; the DME conversion was 95%, H2 yield was 95%, and CO concentration was 0.8 mol.%. I have developed new catalysts for H2 production from DME, and the catalysts give us a great potential for H2 supply from DME. 11347 Geomechanics Issues of the Methane Hydrate Production and Related Material Properties 18th ASCE Engineering Mechanics Conference 2007/6/4 Koji Yamamoto(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］This paper describes the importance of the mechanical properties of the methane hydrate bearing sediments for gas production from the solid form of the hydrocarbon. The dissociation and association processes of the gas hydrate in granular material are coupled phenomena of the thermodynamic condition change, fluid (gas and water) flow, and also the mechanical deformation and failure. Hydrate dissociation and association change the mechanical properties, and deformation and failure make thermal and flow conditions of the material different. This process may cause several issues on the field development for gas production, such as borehole instability, instability of the reservoir formation and surface, near wellbore phenomena and so on 11346 MECHANICAL PROPERTIES OF POST-DISSOCIATION METHANE HYDRATE BEARING SEDIMENTS AND SOLID PRODUCTION MECHANISM 18th ASCE Engineering Mechanics Conference 2007/6/4 Koji Yamamoto(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team Reported in this paper is a laboratory experimental study on mechanical properties of the core materials and solid production behaviour in post-dissociation methane hydrate-bearing formations. The compressive triaxial and direct tensile strength properties were evaluated on re-constituted core materials at room temperature. A number of laboratory solid production experiments were carried out on the same core materials to examine simulated perforation tunnel stability and solid production behaviour. It was found that at a low water saturation (〜30%), a cone shaped cavity could be formed on the sand face and remain stable for an injection pressure of 1MPa if the flowing fluid was gas. However, this injection was reduced to 0.1 to 0.2 MPa if the injection fluid was brine water. At a higher water saturation (〜70%), a stable cavity was not observed. Sand production was induced at an injection pressure of 0.1-0.2 MPa for both gas and water injection. Sand production behavior appeared not to be affected by the hole size on the sand face. 11343 Catalysts for direct synthesis of dimethyl ether from synthesis gas The 11th Korea-Japan Symposium on Catalysis 2007/5/22 Kaoru Takeishi（Shizuoka Univ.) Research Project Team on Emerging Gas Technologies ［Abstract］Copper alumina catalysts prepared by a sol-gel method that is appropriate for DME steam reforming are applied for the DME direct synthesis (3H2 + 3CO → CH3OCH3 + 2CO2) that is similar reaction of DME steam reforming (CH3OCH3 + 3H2O → 3H2 + 2CO2). Much amount of DME was produced over Cu-Zn/Al2O3 catalyst prepared by the sol-gel method, at the lower reaction temperature of 250ºC. The less amount of DME was produced over the mixed catalyst of the methanol synthesis catalyst (N211) and the methanol dehydration catalyst (BK-105), at the higher reaction temperature of 310ºC. The single type catalyst that has copper sites for methanol synthesis and alumina sites for methanol dehydration on the surface is more appropriate and more excellent for DME direct synthesis than the mixed catalyst that is one of the patent catalysts for DME direct synthesis. 11329 Basin Modeling on Formation of Methane Hydrate Including Generation and Migration of Microbial Methane AAPG(American Association of Petroleum Geologists)HEDBERG CONFERENCE "Basin Modeling Perspectives: Innovative Developments and Novel Applications" 2007/5/9 Akihiko Okui(Idemitsu Oil and Gas Co.,Ltd.), Ryosuke Aoyagi(Mizuho Information and Research Institute,Inc.), Martin Schoell（Gas Consult International Inc.）, Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Exploration and development for gas hydrate is hot issue in Japan now. Estimation of its resources is essential in initial stage of investigation. Understanding of generation and migration of methane as well as formation of methane hydrate is very helpful for this kind of study like petroleum system for oil and gas exploration. A basin model, which can simulate the formation of methane hydrate as well as generation and migration of microbial methane was developed and then was used for the evaluation of methane hydrate in Nankai Trough area in Japan 11327 Estimation of Petrophysical Parameters from 3D images of Carbonate Core SPWLA Middle East Regional Symposium 2007/4/15-19 R.M.Sok, C.H.Arns(Australian National Univ.), M.A.Knackstedt(Australian National Univ/University of New South Wales), T.J.Senden, A.P.Sheppard, H.Averdunk(Australian National Univ.), W.V.Pinczewski(University of New South Wales), Hiroshi Okabe(Japan Oil, Gas and Metals National Corporation) Research Project Team on Subsurface Technologies for Field Development ［Abstract］Carbonate rocks are diverse and their pore space complex. Large variations in petrophysical properties of carbonates are caused by wide variations in pore type, pore shape and pore interconnectivity. Petrophysical properties such as capillary pressure and Archie m,n values of carbonate rocks are directly related to the amount and type of porosity, the dominant feature size and the interconnectivity of different porosity groups. While the petrophysical properties strongly depend on the interconnectivity of pores and pore shapes, accurately measuring these attributes requires the analysis of pore structure in 3D. Until recently this has not been possible, and traditional descriptions of carbonate pore structure and interconnectivity have been inferred from 2D thin section analysis. In this paper we describe the imaging of a number of carbonate core samples from the UAE in 3D across a range of scales down to 2.8 microns. The samples include sucrosic dolomites and a complex bioclastic grain/packstone. We calculate drainage capillary pressure and resistivity as a function of saturation directly on the images and correlate the resultant petrophysical properties to the pore structure of the rock. While the dolomite samples exhibit a dominant and strongly interconnected macroporous phase (pore throats 4μm), the bioclastic sample exhibits a significant proportion of meso/microporosity (pore throats 4μm). Pore connectivity is studied for both sets of samples. The connectivity of the sucrosic dolomite exhibits a strong trend of lower connectivity with decreasing porosity. Other pore structural properties (e.g., pore size, pore-to-throat aspect ratio, pore and throat shape) show little variation. The bioclastic sample has significant proportions of both connected and disconnected (separate) macropores. It is shown that inclusion of larger pores associated with the mesoporous phase results in complete connectivity of the macroporous phase. The relative interconnectivity of the macropores is systematically related to the resultant Archie cementation exponent. The saturation exponent n is calculated for water-wet and oil-wet conditions. Strong differences in n with wettability are noted for the sucrosic samples. The inclusion of microporosity has a dramatic effect on the behaviour of n for the bioclastic sample. Three dimensional imaging and analysis of carbonate core material at the pore scale can provide a basis for more accurate petrophysical models, narrow the range of uncertainty in estimates of petrophysical properties and improve the quantification of the resource within carbonate reservoirs. 11326 Feasibility Study of Marine Controlled-Source Electromagnetic for Gas Hydrate The 11th International Symposium on Recent Advances in Exploration Geophysics (RAEG 2007) in Kyoto 2007/4/15-16 Kazunobu Yamane(Geothermal Energy Research & Development Co.,Ltd), Tatsuo Saeki, Takao Inamori(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Marine controlled source electromagnetic method may be one of the most significant new technologies for hydrocarbon exploration. The promise for the technology lies in its ability to differentiate resistive, potentially oil-bearing intervals from surrounding, more conductive water-bearing units. The principle is the same as that used in well logging devices to identify hydrocarbon zones in well bores. The technique is not new but the capability to resolve relatively thin resistive intervals in the depth offers new promise to lower the risk through direct hydrocarbon indicators in conjunction with modern seismic methods. In this paper, we discuss the capability of marine CSEM method towards gas hydrate exploration by numerical studies of 1-D modeling and 2.5-D inversion. 11325 Geological interpretation of the northern part of the Kumano basin using 3D reflection seismic data The 11th International Symposium on Recent Advances in Exploration Geophysics (RAEG 2007) in Kyoto 2007/4/15-16 Tatsuo Saeki, Takao Inamori, Sadao Nagakubo(Japan Oil, Gas and Metals National Corporation), Sumito Morita(AIST), Osamu Takano(JAPEX) Methane Hydrate Research Project Team ［Abstract］Conventionally, BSRs (bottom simulating reflectors), which are considered to be a bottom of the gas hydrate bearing sediment, have been picked as the reflectors in parallel with sea-bottom topography. The interpretation of 3D reflection seismic data revealed that the BSR in the Kumano basin include two types of local pull-up phenomenon that had no correlation with the sea- bottom topography The most remarkable BSR pull-up phenomena (type-A) occurred in the small circle area of 400m in diameter and the topography is like a mountain. The center top was closed to the sea-bottom in which the pockmark existed. Another type anomaly (type-B) consisted of several small pull-ups distributed in a line. Seismic velocity analysis showed that there were local high velocity anomalies directly above them, which could cause apparent BSR pull-ups. The geological interpretation suggested the possibility that above high velocities occurred due to concentrations of gas hydrate. On the other hand, the mountain type BSR pull-up might be related with the local variation of the thermal condition. 11317 Study on the deployment of accelerometers in reflection seismic surveys International Workshop on Underwater Technology/Scientific Use of Submarine Cables and Related Technologies 2007 2007/4/17-20 Hiroo Takahashi(OCC Corporation）, Eichi Asakawa（JGI,Inc.,), Yuji Kawai(Nippon Salvage Co.,Ltd.,), Yukitoshi Ogasawara(Kokusai Cable Ship Co.,Ltd.,), Tastuo Saeki(Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Team ［Abstract］The RSCS (Real-time Seismic Cable System) is an optical submarine cable system with a series of three component velocity type sensors mounted in a pressure resistant case that can withstand hydraulic pressures up to 800 atmospheres (78.4 MPa). Spreads consisting of several of the above mentioned velocity type sensors, spaced at 50 meters interval, have been deployed during actual offshore reflection seismic survey operations. The resulting data quality acquired with RSCS was reported to be excellent and effectiveness of the system for reflection seismic survey demonstrated [Asakawa et al (2006)] Recently, the application of acceleration type sensors in the RSCS was studied. For comparison purposes, a system equipped with velocity type sensors and the acceleration type sensor was deployed during reflection seismic survey operations in an area with a water depth of about 1000m. Data acquired with both sensor types were excellent, confirming that RSCS equipped with the acceleration type sensor is also effective for reflection seismic surveys. Application of acceleration type sensors in the RSCS may allow reduction the size of sensor units because gimbal mechanism, necessary for keeping velocity sensor orientation horizontal, will no longer be necessary. 11316 Real-time Seismic Cable System (2) EGU2007 General Assembly 2007/4/15-21 Eichi Asakawa（JGI,Inc.,), Yuji Kawai(Nippon Salvage Co.,Ltd.,), Hiroo Takahashi(OCC Corporation）, Yukitoshi Ogasawara(Kokusai Cable Ship Co.,Ltd.,), Tastuo Saeki(Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Team ［Abstract］RSCS (Real-time seismic Cable System) is a new real-time seafloor reflection seismic observation system. It is a series of 3-component geophones and telemetry optoelectronics equipped into a high pressure resistant housing, which enables real-time seismic data acquisition at ultra deep sea. The first reflection seismic survey was carried out in March 2006. The geophone data show the high quality with the advantage such as precise timing with GPS link on board and superior sensor directivity. It is worthwhile for P-S converted wave processing as well as for P-P processing. The data processing is different from the conventional reflection seismic such as CDP method in the viewpoint of its geometry and P-S conversion. Precise velocity analysis and prestack migration solve the problem of its elevation difference between shot (sea surface) and receiver (sea bottom) point. The second seismic survey has been carried out in December 2006, equipped with accelerometer and hydrophone. These data was also very high quality as same as the geophone data. The accelerometer implies that the geophone will be replaceable with accelerometer. It means that there is a possibility to reduce the sensor size without gimbals. The hydrophone data is similar to the geophone data except the polarity change. This characteristic enables us to separate upgoing reflection from downgoing wave which includes only direct water waves and multiple reflections. The total data quality so far is very good compared to the conventional OBS systems. The RSCS has a great potential as a seabed observation system. 11314 Characterizing gas hydrate reservoirs using well log data Hart's E&P 2006/5/25 Doug Murray, Masafumi Fukuhara, Osamu Osawa,Tatsuki Endo, Robert Kleinberg, Bikash Sinha(Schlumberger), Takatoshi Namikawa(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Characterizing gas hydrate reservoirs using well log data 11312 Contribution of Methane Accumulation and Pore Water Flow to Forming High Concentration of Methane Hydrate in Sandy Sediments 2006 AGU Fall Meeting 2006/12/11-15 Takashi Uchida, Amane Waseda(JAPEX), Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Contribution of Methane Accumulation and Pore Water Flow to Forming High Concentration of Methane Hydrate in Sandy Sediments 11311 Research and Development Studies of the Mallik Gas HydrateDeposit, Mackenzie Delta, NWT 34th Annual Yellowknife Geoscience Forum(2006) 2006/11/21-22 Scott R Dallimore(Geological Survey of Canada ）, Kenichi Yokoi, Yutaka Imasato(Japan Oil, Gas and Metals National Corporation) , Andrew Applejohn (Aurora Research Institute) Methane Hydrate Research Project Team ［Abstract］Research and Development Studies of the Mallik Gas HydrateDeposit, Mackenzie Delta, NWT 11309 Characteristics of Arenite Sand Containing Highly-Saturated Gas Hydrate in Pore System: Hydrogeological Implications for Methane and Pore Water Accumulation GSA (Geological Society of America) 2006/10/22-25 Takashi Uchida, Amane Waseda(JAPEX), Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Gas hydrates are widespread in many deep marine environments along continental margins worldwide as well as in several Arctic sedimentary basins associated with permafrost. Plenty of gas hydrate-bearing send core samples have been obtained from the Nankai Trough as well as Mallik areas. The Nankai Trough runs along the Japanese Island from offshore Tokai to offshore Kyushu, where forearc basins and accretionary prisms d eveloped extensively and distinct BSRs (bottom simulating reflectors) as well as intensive thrust/growth faults have been broadly recognized. The MITI Nanakai Torough wells and METI Tokaioki to Kumanonada wells were drilled in 2000 and 2004, and the Mallik 2L-38 and Mallik 5L-38 research wells were drilled at the Mallik site, Northwest Territories, Canada, in 1998 and 2002. The chloride content anomalies in extracted pore waters, core temperature depression, core observations, visible gas hydrates as well as continuous downhole well log data confirm common occurrences of pore-space hydrate as intergranular pore filling within sandy layers, which clarified the characteristics of subsurface natural gas hydrate beneath deep sea floors and permafrost zones. Gas hydrate saturations are generally evaluated up to 80% in pore volume, which may need gas accumulation associated with pore water and original pore space large enough to occur within host sediments. According to grain size distributions most of pore-space gas hydrates are contained in coarse-to very fine-grained sandy strata, and they are scarcely contained in finer-grained sediments such as siltstone and claystone. Based on the geochemical and geological data, microbial methane migration processes are estimated to be active flow to permeable sandy layers in the Nankai Trough, and long migration of thermogenic methane generated in deep mature sediments at the Mallik. Subsequent sedimentological analyses performed on gas hydrate-bearing sandy sediments and well log data also revealed important geologic and sedimentological controls on the formation and preservation of natural gas hydrate. It should be noted that in both of the terrestrial (Mallik) and the marine (Nankai Trough) areas distributions of porous and coarser-grained host rocks should be one of the most important factors to control the occurrence of pore space hydrate. This study was performed as a part of the MH21 Research Consortium on methane hydrate in Japan. 11308 Thin Bed Analysis of Gas Hydrate Bearing Sands in the Nankai Trough The 12th Formation Evaluation Symposium of Japan 2006/10/4-5 Doug Murray・Steve Alderman(Schlumberger), Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation), Masafumi Fukuhara(Schlumberger) Methane Hydrate Research Project Team ［Abstract］Gas Hydrates are white crystalline solids composed of gas (usually methane) and water. The gas molecules are densely packed and contain large amounts of energy. Hydrates are commonly found in deep offshore; shallow seabed sediments and below permanent frost in arctic areas where the environmental conditions of moderately low temperature and moderately high pressure are conducive to hydrate formation. Many techniques have been developed in gas hydrate reservoir formation evaluation to describe the amount of hydrate present in a rock. Mostly, these techniques depend on the measured responses of the resistivity, nuclear, acoustic and magnetic resonance geophysical logs. These techniques have proven robust and are dependent on the underlying resolution of the measurement. Depending on the measurement vintage and type, the vertical resolution of geophysical logs can vary from〜5 mm to〜3meters. This is not a significant issue when the reservoir bed thickness is greater than 3 meters but can play an important role in thinly laminated reservoirs like those found in shallow seabed sediments. This paper presents an approach to resolve some of these vertical resolution issues. Its fundamental assumption is that the highest resolution measurement can be used to model the thin bed response of the lower resolution measurements. For wireline the highest resolution device is the borehole electrical imaging tool with a vertical resolution of 〜5mm. For Logging-While-Drilling (LWD) the laterolog resistivity measured at the bit has the highest resolution at〜5cm. 11307 The Mallik Gas Hydrate Field, Mackenzie Delta, Canada:A Summary of Reseach and Development Studies of a Tereestrial Gas Hydrate Deposit ISC2006 2006/8/27-9/1 SCOTT R. DALLIMORE・TIMOTHY S. COLLETT(Geological Survey of Canada）, Kenichi Yokoi, Yoshihiro Tsuji(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］The Mallik Gas Hydrate Field, Mackenzie Delta, Canada:A Summary of Reseach and Development Studies of a Tereestrial Gas Hydrate Deposit 11306 Characterization of gas hydrate-bearing sediments for an attempt to resource assessment, eastern Nankai Trough, Japan ISC2006 2006/8/27-9/1 Tetsuya Fujii, Takatoshi Namikawa, Masaru Nakamizu(Japan Oil, Gas and Metals National Corporation), Mizue Nishimura, Osamu Takano(JAPEX), Yoshihiro Tsuji(Japan Oil, Gas and Metals National Corporation)　 Methane Hydrate Research Project Team ［Abstract］Characterization of gas hydrate-bearing sediments for an attempt to resource assessment, eastern Nankai Trough, Japan 11305 Experimental investigation on the role of clay minerals in natural gas hydrate formation. WPGM (Western Pacific Geophysics Meeting) 2006/7/24-27 Tatsuji Kawasaki(Japan Oil, Gas and Metals National Corporation), Hailong Lu, John Ripmeester, Igor Moudrakovski, Jong-won Le（National Research Council Canada), Tetsuya Fujii, Masaru Nakamizu(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Except for those occurring at seafloor, natural gas hydrates exist in sediments, subject to the influence of sediment particles. Many of the physical and chemical properties of sediment can affect the formation of natural gas hydrate, for example, pore size, mineral compositions, size of sediment particle, etc. Unfortunately the mechanism by which these factors work during the formation of natural gas hydrate has not been well understood. Present research aims at elucidating the role of clay minerals, one of the factors, in hydrate formation through experimental investigations. The results of the P-T stability conditions of methane hydrate in various water saturated clay minerals, indicated that clay minerals are thermodynamic inhibitor for gas hydrate formation, shifting the stability condition to a regime of relatively high temperature and low pressure, while in situ observations on methane hydrate formation in clay minerals by MRI (Magnetic Resonance Imaging) found that clay minerals are kinetic promoter for gas hydrate formation, shortening the induction time greatly as compared with quartz sand. Guggenheim and Koster van Gross(2003) claimed the formation of methane hydrate in the interlayer of Na-montmorillonite with a reflection at 2 theta=〜4°in X-ray diffraction spectrum, but the results of our experiments showed that this reflection can appear without hydrate occurrence when water content in Na-montmorillonites is 59%. Thus, more effects are needed to confirm hydrate formation in the interlayer of Na-montmorillonite. 11304 Development of 2D simulator for methane hydrate accumulation in basin scale.　-Evaluation of the controlling factor of methane hydrate accumulation In the eastern Nankai Trough- WPGM (Western Pacific Geophysics Meeting) 2006/7/24-27 Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation), Ryosuke Aoyagi, Yutaka Nakama, Minoru Yoshikawa(Mizuho Information & Research Institute Inc.）、Akihiko Okui(Idemitsu Oil and Gas Co.,Ltd.), Tatsuji Kawasaki, Masaru Nakamizu(Japan Oil, Gas and Metals National Corporation)　 Methane Hydrate Research Project Team ［Abstract］In order to simulate geological/geophysical phenomenon related to methane hydrate (MH) accumulation in the deep marine sediments, and to clarify the controlling factor for MH accumulation, we have developed 2-D simulator for MH accumulation. This simulator is modified version of "SIGMA-2D" which is 2-D multi phase fluid flow basin simulator for petroleum generation, migration and accumulation developed by JOGMEC (former JNOC) Technology & Research Center [1]. New models dealing with biogenic methane generation and MH formation/dissociation were installed in the prototype of the simulator for this study [2]. Empirical model by Schoell (2005) was used for the biogenic methane generation. In this model, gas generation rate is estimated from maximum gas generation rate and its vertical attenuation rate, which were derived from ODP gas sample analysis. We have also extracted biogenic methane generation parameter, which was consistent with the actual MH accumulation at one of the site In the eastern Nankai Trough. We have also modified MH formation/dissociation model in order to evaluated MH formation timing precisely. Reaction-rate model considering the temperature/pressure dependence of reaction factor was installed for the prototype simulator. We have conducted test simulation (case study) for 2-D section In the eastern Nankai Trough using core, well log and seismic data obtained from multi-well drilling program METI "Tokai-oki to Kumano-nada". The controlling factors of MH accumulation were examined based on the results. This study was conducted as a part of research consortium for methane hydrate resources in Japan (MH21). [1]Okui,A.,Siebert,R.M. and Mtsubayashi,H.(1998):Simulation of oil expulsion by 1-D and 2-D basin modeling ・saturation threshold and relative permeability of source rocks. Geological Society, London, Special Publications,141,45-72. [2]Okui,A.,Nakamizu,M.,Fujii, T.. and Aoyagi,R.(2005): Evaluation of Methane Hydrate Formation by Computer Simulation, Abstract of 23nd Japan Symposium on Organoc Geochemistry,July 28-29,2005 Kochi Univ.,Japan,O-16. 11303 Data Acquisition and Well Construction Experiments for Future Marine Gas-Hydrate Production WPGM (Western Pacific Geophysics Meeting) 2006/7/24-27 Koji Yamamoto, Maki Matsuzawa(Japan Oil, Gas and Metals National Corporation), Doug Murray,Khong Chee Kin(Schlumberger), Masato Yasuda(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Data Acquisition and Well Construction Experiments for Future Marine Gas-Hydrate Production 11295 Comprehensive Approach of Core Analysis to Predict Water Flooding Performance in a Heterogeneous Carbonate Reservoir, Offshore Abu Dhabi 12th Abu Dhabi International Petroleum Exhibition and Conference　(ADIPEC) 2006/10/7 Kazuhito Oseto(Japan Oil, Gas and Metals National Corporation), A. Al-Amoudi(Abu Dhabi National Oil Company), Masayoshi Suzuki(Abu Dhabi Oil Company Ltd.) Research Project Team on Subsurface Technologies for Field Development ［Abstract］The horizontal carbonate core samples were devoted to special core analysis to evaluate the field waterflooding performance in offshore Abu Dhabi under the observation of X-ray CT scanner at both fresh and aged states. Judging by visual observation of the surface and X-ray CT scanning, the core is apparently heterogeneous locally having some algal fragments which form vuggy pore spaces and some minerals which can form low porosity region. The main objective of this study was therefore to evaluate the effects of such heterogeneity on waterflooding performance and subsequent oil recovery. For fresh cores, the results of Amott and USBM tests indicated neutrally wet to water wet nature that contradicted the expected. It was inferred that the contamination of a drilling fluid might alter the original wettability condition. The water flooding experiment with this condition resulted in fairly high oil recovery. X-ray CT scanning supported the result by demonstrating uniform water frontal advancement and high sweep efficiency in consequence. The same manner was applied to an aged core where the results on Amott and USBM tests indicated oil wet nature. The oil recovery was a little less than that for the fresh core but still favorable. X-ray CT scanning demonstrated uniform flow as well. In this way, the experiments proved high oil recovery for the aged cores as well in spite of the locally existing heterogeneities. Kr curves derived by employing JBN method for both the fresh and the aged cores had a little different shape. The curves for the aged core were verified with on-dimensional coreflood simulation model. Thus, this paper presents the detail of the waterflooding under X-ray CT scanning and comprehensive approach of the core analysis as a case study. 11284 GTL Demonstration Test Project GTL tec2007 2007/1/23 Yoichi Norisugi(Japan Oil, Gas and Metals National Corporation) Research Project Team on Emerging Gas Technologies ［Abstract］(1)Introduction-Development of JAPAN-GTL Process (2)Nippon GTL Technology Research Association (3)GTL Demonstration Test Project (4)Conclution 11278 230Th/234U and 14C dating of a Lowstand Coral Reef beneath the Insular Shelf off Irabu Island, Ryukyus, southwestern Japan The Island Arc 2006/12 Keiichi Sasaki（Kanazawa Gakuin Univ.), Akio Omura, Akihiro Miwa（Kanazawa Univ.）, Yoshihiro Tsuji （Japan Oil, Gas and Metals National Corporation）, Hiroki Matsuda （Kumamoto Univ.）, Toru Nakamori, Yasufumi Iryu, Tsutomu Yamada（Tohoku Univ.）, Yuri Sato （JICA）, and Hiroshi Nakagawa （GeoWindow） Geology & Geophysics Research Team ［Abstract］High-resolution seismic reflection profiles delineated the distribution of mound-shaped reflections, that were interpreted as reefs, beneath the insular shelf western off Irabu Island, Ryukyus, southwestern Japan. A sediment core through one of the mounded structures was recovered from seafloor at -118.2 m by offshore drilling and was dated by radiometric methods. The lithology and the coral fauna of the core indicate that the mounded structure was composed of coral-algal boundstone suggesting a small-scaled coral reef. High-precision α-spectrometric 230Th/234U dating coupled with calibrated AMS 14C ages of corals obtained reliable ages of this reef ranging from 22.18±0.63 to 30.47±0.98 ka. This proves that such a submerged reef was formed during the lowstand stage of the marine oxygen isotope stages 3 to 2. The existence of low-Mg calcite in aragonitic coral skeleton of 22.18±0.63 ka provides an evidence that the reef has once been exposed by lowering of relative sea level to at least -126 m during the last glacial maximum in the study area. There is no room for doubt that a coral reef has grown during the last glacial period on the shelf off Irabu Island of Ryukyus in the subtropical region of western Pacific. 11276 Simulating Transient Behavior of Cuttings Transport over Whole Trajectory of Extended Reach Well IADC/SPE Asia Pacific Drilling Technology Conferense and Exhibition 2006/11/13-15 Shigemi Naganawa(Tokyo Univ.), Tsuyoshi Nomura(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Team ［Abstract］Based on our previously developed prototype simulator, a transient cuttings transport simulator using the two-layer model was developed with some modifications and improvements for more practical use. To evaluate functionality and potential of the simulator, a post analysis on hole cleaning were carried out for an actual extend reach well (ERW) drilled in Japan. Simulation results showed that the modified model successfully demonstrated transient distributions of cuttings bed height and annular pressure over the whole trajectory of the well. From the comparison with a conventional steady-state analysis, transient simulation over the whole trajectory was found to be crucial and useful for prediction of behaviors unrecognized by steady-state simulations. 11271 High concentrated gas hydrate zone imaged in seismic data 2006 AGU(American Geophysical Union) Fall Meeting 2006/12/13 Toshiaki Kobayashi, Tatsuo Saeki, Nobutaka Oikawa, Takao Inamori, Tetsuya Fujii, Tokujirou Takayama, Masao Hayashi, Masaru Nakamizu(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Japan Oil, Gas and Metals National Corporation (JOGMEC), as a member of MH21 Research Consortium, takes charge of a study of the Research for Resources Assessment, and is pursuing a possibility that gas hydrate, which is presumed to be distributed around ocean area of Japan, will be energy resources. As part of the study, 3D seismic survey was conducted from Tokai-oki to Kumano-Nada In the eastern Nankai Trough by METI (Ministry of Economy, Trade and Industry) in 2002 under the national Program of assessment for gas hydrates as energy resources. As well as 3D seismic survey, drilling program was conducted in this area and information of physical property was acquired. Additionally, velocity analysis and seismic attribute analysis were conducted. It is revealed that gas hydrate zone is correlated with high resistivity and high velocity, and a lot of gas hydrates are found in turbidite sand with much porosity. JOGMEC is conducting analysis of seismic data and is doing resources assessment of gas hydrate compiling information of physical property which was acquired by drilling, result of velocity analysis, and result of seismic attribute analysis. This time, we introduce some seismic images of high concentrated gas hydrate zone appears in Tokai-oki area. 11270 The Influences of Clay Minerals on Methane Hydrate Formation 2006 AGU(American Geophysical Union) Fall Meeting 2006/12/13 Tatsuji Kawasaki(Japan Oil, Gas and Metals National Corporation), Hailong Lu, John Ripmeester, Huang Zeng, Jong-won Lee, Igor Moudrakovski(Steacie Institute for Molecular Sciences, National Research Council Canada), Tetsuya Fujii, Masaru Nakamizu(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Natural gas hydrates exist in sediment, either filling sediment pores or locally aggregated as nodular or massive hydrate. The elucidation of the role of the sediment matrix on gas hydrate formation is crucial to understanding the formation mechanism and accumulation of methane hydrate in natural environments. Clay minerals are common constituents of natural sediments. From the results of field and laboratory investigations, as well as theoretical studies, clay minerals are likely to play an important role in controlling the occurrence of natural gas hydrate. However the mechanism of how clay minerals affect hydrate formation is still not well understood. Present research aims at elucidating the role of clay minerals in hydrate formation through experimental investigations. Three types of clays typical of natural sediments have been selected as the test materials: Na-montmorillonite, Ca-montmorillonite, and Kaolinite. Na-montmorillonite and Ca-montmorillonite are 2:1 types, among which interlayer distances (d-spacing) of Na-montmorillonite and Ca-montmorillonite can increase when soaked in water, while the former has much stronger swelling ability than the latter. Kaolinite is 1:1 type, not able to expand its interlayer distance. For the purpose of comparison, quartz was also tested. The results of the P-T stability conditions of methane hydrate in various water-saturated clay minerals, indicated that Ca-montmorillonite and kaolinite are thermodynamic inhibitors for gas hydrate formation, shifting the stability conditions to a regime of relatively lower temperature and higher pressure, while in situ observations on methane hydrate formation in clay minerals by MRI (Magnetic Resonance Imaging) found that clay minerals are kinetic promoters of gas hydrate formation, shortening the induction time greatly as compared to quartz sand. 11267 Seamount subduction to the Nankai accretionary wedge and its impact on methane hydrate accumulation: insights from analogue and numerical models 2006 AGU(American Geophysical Union) Fall Meeting 2006/12/11-15 Yasuhiro Yamada, Naoki Nagamura(Kyoto Univ.), Kei Baba(JAPEX), Toshifumi Matsuoka(Kyoto Univ.) Methane Hydrate Research Project Team ［Abstract］Seamount subduction to the Nankai accretionary wedge and its impact on methane hydrate accumulation: insights from analogue and numerical models 11265 Geomechanical property of gas hydrate-bearing zone 2006 AGU(American Geophysical Union) Fall Meeting 2006/12/11-15 Masami Hato, Hiroyuki Ikeda(Kyoto Univ.), Takao Inamori(Japan Oil, Gas and Metals National Corporation), Kiyofumi Suzuki(AIST), Toshifumi Matsuoka(Kyoto Univ.) Methane Hydrate Research Project Team ［Abstract］For the development of gas hydrate as possible future energy resources, the great effort has been paid for developing new seismic methods to delineate hydrate reservoir and its quantification. Not only for reservoir delineation but also for understanding gas hydrate system and geological history of hydrate sediment, we have made a geomechanical study for hydrate and non-hydrate sediment theoretically and experimentally using the well data and core samples acquired in Nankai Trough area. In first step of the study, we have tried to calculate the mechanical strength of the gas hydrate-bearing sediment based on the Coulomb-Mohr failure criterion using well-logging data. The result shows that the sediment below the gas hydrate-bearing layer is apparently mechanically weaker than gas hydrate-bearing layer. This result is consistent with our knowledge that caliper data shows the weakness of the well-bore Wall. In second step, we measured the mechanical strength of the core samples recovered by PTCS at the Nankai Trough area The measurement was made to the core samples, one of which is under in situ condition and another of which was done after dissociation. As a result, the strength of the gas hydrate-contained core with high saturation is about 4 times stronger than that of gas hydrate-dissociated core. This result is completely same as that of calculated strength using the well-logging data. These information will be important for reservoir monitoring while production and hazard prevention while drilling. 11266 Delineation of gas hydrate-bearing sediments by multi seismic attributes using 3D seismic survey in the eastern Nankai Trough 2006 AGU(American Geophysical Union) Fall Meeting 2006/12/11-15 Takao Inamori, Tatsuo Saeki, Masao Hayashi, Toshiaki Kobayashi, Nobutaka Oikawa, Tokujirou Takayama, Tetsuya Fujii, Masaru Nakamizu(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］In 2000, the occurrence of gas hydrates was confirmed by corings and borehole log measurements In the eastern Nankai Trough offshore Japan. We conducted the 3D seismic survey in this area in 2002, we decided well sites and drilled thirty-two boreholes in 2004. We had gotten many logs and cores which indicated the occurrence of gas hydrate below the sea floor. Bottom Simulating Reflectors (BSRs) were widely found on the marine seismic data acquired in the shelf - slope In the eastern Nankai Trough area. BSRs indicate the existence of gas hydrates. However, we cannot estimate detail reservoir information from distribution of BSRs. The gas hydrate-bearing sediments are heterogeneous and complex both vertically and horizontally, because gas hydrate concentrated layers are mainly turbidite sands. If we will explore and exploit the gas hydrate, we have to get the reservoir characterization of hydrate-bearing sediments, such as its concentration, porosity or thickness. In order to estimate the amount of gas hydrates accurately, we need to get the more detailed reservoir parameters from seismic data. We apply the seismic attributes analysis to 3D seismic survey data to delineate distribution of gas hydrate-bearing sediments. We calculate seismic attributes of the P- interval velocity using the dense NMO velocity analysis, P-impedance, S-impedance, and Poisson’s ratio change from pre-stack (AVO) analysis and the attenuation attribute. High P-interval velocity, High P & S impedance, low Poisson’s ratio and high attenuated layers correspond to the hydrate bearing-zones. 11263 New catalysts for hydrogen production by steam reforming of dimethyl ether 4th Asian Pacific Congress on Catalysis 2006/12/8 Kaoru Takeishi(Shizuoka Univ.) Research Project Team on Emerging Gas Technologies ［Abstract］Dimethyl ether (DME) is expected as a clean fuel of this 21st century. I have developed Cu-Zn/Al2O3 catalysts prepared by a sol-gel method for hydrogen production by DME steam reforming. The catalysts produce hydrogen more effectively than mixed catalysts with DME hydrolysis catalysts and methanol steam reforming catalysts. SEM-EDS analyses have suggested that the Cu-Zn/Al2O3 catalysts have the catalyst surface structure that is appropriate for the steam reforming of DME consisting of DME hydrolysis and methanol steam reforming. Experiments on the effect of the space velocity, durability test, and other experiments have suggested that the further developments are still need but the catalysts have enough capability for practical use. 11261 History Matching with Combustion Tube Tests for Light Oil Air Injection Project SPE International Oil & Gas Conference and Exhibition in China 2006/12/6 Takeshi Onishi, Komei Okatsu(Japan Oil, Gas and Metals National Corporation), Tetsuo Teramoto(Teikoku Oil) Petroleum Engineering Research Team ［Abstract］A series of experiments is essential in light oil air injection (LOAI) study. Accelerating Rate Calorimeter (ARC) test, Thermo Gravimetric Pressurized Differential Scanning Calorimeter (TG/PDSC) test and Combustion Tube (CT) test are generally conducted to evaluate a potential of air injection in fields. ARC test is used to determine the extent and continuity of reactions in the low and high temperature range. TG/PDSC test also helps to identify the temperature ranges over which oil reacts with the oxygen. The purposes of the CT test are (1) to assess the overall burning characteristics of oil, (2) to measure incremental oil production, air and fuel requirements and other parameters and (3) to measure produced gas compositions and oil and water production to provide benchmarks for monitoring future field operations. On this series of experimental work, using domestic oilfield sample, two CT tests were conducted, in low water saturation case and high water saturation case after waterflooding, to estimate the applicability of LOAI including on tertiary mode. Both tests showed stable combustion performance in terms of temperature, pressure response, produced gas compositions and incremental oil production. On the other hand, numerical simulation is important to predict field production performance. The appropriate reaction kinetics on the combustion has to be used in the numerical simulation. History matching with CT tests were conducted to obtain the kinetics, and two kinds of reactions, “oxidation reaction” and “combustion reaction” were used in the study. In the former reaction, oxygen is consumed by the oil to form oxidation compounds. In the latter one, oxygen reacts with the compounds to form carbon dioxide and water. Reaction parameters were used as matching parameters. Results of history matching with both CT tests using same reaction kinetics were obtained. This paper presents the results of the CT tests and the history matching studies with these tests and also some discussion of the air injection process. 11260 Gas to Wire System (GTW) for Developing “Small Gas Field” and Exploiting “Associated Gas” SPE International Oil & Gas Conference and Exhibition in China 2006/12/6 Tomoko Watanabe(Japan Oil, Gas and Metals National Corporation), Hiroshi Inoue, Mutsumi Horitsugi(Hitachi Ltd.), Shunichi Oya(JGC) Petroleum Engineering Research Team ［Abstract］A new development concept of marginal gas field and associated gas with a reserve between 10 bcf and 1 tcf is suggested. This concept is called as a Gas to Wire System (GTW), which means onsite power generation by produced gas. Because of no need of transportation of the produced gas, GTW is considered to be high efficiency system with merits from economic and environmental perspective. Japan Oil, Gas and Metals National Corporation (JOGMEC), Hitachi, Ltd., JGC Corporation, Toyohashi University of Technology, and Arabian Oil Company have advanced the research project on high efficiency of totally 50 % thermal efficiency, low cost and low emission GTW by applying Gas Turbine Combined Cycle System (GTCC). The targets of this project are (1) the development of the new burner which is available both gas and oil (NOx emission <25 ppm for gas, <80ppm for oil/ oil + gas, and combustion efficiency >99.9%), (2) the design of the low cost pre-treatment for fuel. The technology (1) would add the cost value of the generator itself and give the GTW system the back-up fuel. The test facility for the technology (1) was prepared and the design and construction of small model burners was carried out. The result of small model burner test shows low NOx emission for both oil and gas. Investigation of particulate material /soot formation affected by fuel properties and impurities was carried out. Corrosion test equipments were designed and constructed. Process flow of available treatment equipments was composed with consideration for impurities permission levels for gas turbine as the technology (2). The tentative feasibility study was carried out. It shows that GTW system makes a marginal gas field valuable and has less power loss from well to GTCC. The subjects in near future are achievement of each target for the developments, conceptual design of GTW system for selected gas field and the assessment of economical feasibility. 11258 A new visualization era in geology and sedimentology: impact of the development of 3D seismic technology 8th Society of Exploration Geophysicists of Japan Internationl Symposium 2006/11/28 Osamu Takano(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Team ［Abstract］Recent developments of 3D seismic and 3D visualization technologies have provided a strong impact on geological sciences, such as sedimentology, structural geology, petrology, petroleum geology and reservoir engineering, in terms of analytical methodology and concepts. In petroleum geology, 3D seismic technology has been widely applied for exploration and development projects to detect reservoir rock distributions and to conduct effective reservoir characterization studies. In structural geology, detailed three-dimensional structures, such as folds, faults, salt domes and plate boundaries, have been discussed using 3D visualization technique. In sedimentology, detailed three-dimensional views of sediment body morphology and depositional surfaces, such as fluvial channels, incised valleys, deep-sea channels, slope failures, submarine fans, carbonate reefs and sequence boundary surfaces, have been reconstructed by 3D seismic technology. This dramatic development of paleoenvironmental visualization technique resulted in the new research field “seismic geomorphology” or “seismic sedimentology” as an integrated concept of 3D seismic technology and sequence stratigraphy. The concept and methods of seismic geomorphology have been widely applied for sediment body analysis, three-dimensional depositional process analysis and quantitative reservoir characterization. 3D seismic technology is indispensable for the future earth sciences, as an effective, efficient and precise tool of earth surface dynamics analysis. 11253 Fusion on 3D seismic exploration and seafloor geochemical survey 8th SEGJ International Symposium 2006/11/26-28 Sadao Nagakubo, Toshiaki Kobayashi, Tetsuya Fujii, Takao Inamori(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］MH21 Research Consortium (Research Consortium for Methane Hydrate Resources in Japan) has been conducting seafloor geochemical survey as a method for exploration of methane hydrate reservoir in the eastern Nankai Trough, offshore Japan. However the geological and geochemical settings between methane hydrate reservoirs and seafloor In the eastern Nankai Trough are quite complex. We have to construct a geological and geochemical model in consideration of various settings in sediment for success of seafloor geochemical survey to explore methane hydrate reservoirs. MH21 Research Consortium conducted high-resolution 3D seismic survey to explore methane hydrate reservoir in the eastern Nankai Trough. As the high-resolution 3D seismic survey was designed for shallow formation where methane hydrates exist, we could obtain excellent information about various settings in shallow formation. The high-resolution 3D seismic data provided us information about seafloor manifestations, migration conduits of hydrocarbon-bearing fluids, and geothermal structures in shallow formation. Bathymetric chart and seafloor reflection intensity map constructed by waves reflected from seafloor provided us detailed information about seafloor manifestations. Because occurrences of methane hydrates are strongly restricted by temperature, pressure and other physicochemical environments, BSR (Bottom Simulating Reflector) which is considered as the base of the hydrate stability zone, is represented as not geological event but physicochemical event in seismic sections. We estimated geothermal structures near BSR by anomaly map showing difference of predicted BSR depth by laboratory data and observed BSR depth by high-resolution 3D seismic data. MH21 Research Consortium will continue to conduct seafloor geochemical survey based on the geological and geochemical model constructed using 3D seismic data in the future. In this paper, we introduce an attempt for exploration of methane hydrate reservoirs by ‘Fusion on 3D seismic exploration and seafloor geochemical survey’ in Japan. 11252 Rock mechanical study for methane hydrate-bearing sediment 8th Society of Exploration Geophysicists of Japan Internationl Symposium 2006/11/26-28 Masani Hato,Toshifumi Matsuoka(Kyoto Univ.),Takao Inamori(Japan Oil, Gas and Metals National Corporation),Kiyofumi Suzuki(AIST) Methane Hydrate Research Project Team ［Abstract］For the development of methane hydrate (hereafter called ‘hydrate’) as possible future energy resources, the great effort has been paid for developing new seismic methods to delineate hydrate reservoir and its quantification through the first stage of MH21 national project. Not Only for reservoir delineation but also for understanding hydrate system ( methane generation, migration and　accumulation as a hydrate) and geological history of hydrate sediment, we have made a rock mechanical study for hydrate and non-hydrate sediment theoretically and experimentally using the well data and core samples. As a first step in our study, we have tried to calculate the mechanical strength of the methane hydrate-bearing sediment based on the Coulomb-Mohr failure criterion. As a result, the sediment below the methane hydrate-bearing layer is apparently mechanically weaker than methane hydrate-bearing layer. This result is consistent with our knowledge that caliper data shows the weakness of the well-bore wall. As second step, we also measured the mechanical strength of the core samples recovered at Nankai Trough. The measurement was made to the core samples, one of which is under in situ condition and another of which was done after dissociation. As a result, the strength of the hydrate-contained core of high saturation is about 4 times stronger than that of hydrate-dissociated core. This result is completely same as that of calculated strength using the well-logging data and well-logging (caliper) data. 11251 METHANE HYDRATE QUANTIFICATION FROM MUD LINE TO BOTTOM SIMULATING REFLECTOR 8th Society of Exploration Geophysicists of Japan Internationl Symposium 2006/11/26-28 Richard C.Uden(Rock Solid Images), Jack P.Dvorkin(Stanford Univ./Rock Solid Images), Takao Inamori(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Methane hydrates reside in porous sediment between the sea floor and the bottom simulating reflector. The location and distribution of the sediment where hydrate may form vary laterally and vertically in a very heterogeneous manner. This heterogeneity makes the mapping the quantity of methane hydrate challenging. Here we demonstrate a method that quantifies the total methane hydrate volume accumulated within sediment beds at and below seismic resolution. We also address a problem on the opposite side of the seismic resolution spectrum --the thick layer problem- the quantification of methane hydrate within a reservoir comparable in thickness to the seismic wavelength. When beds are below seismic resolution, the problem is one of scale. Therefore, we pose the problem of hydrate reservoir characterization differently by seeking a scale-independent volumetric reservoir property and a scale-independent seismic attribute to quantify this property. Therefore we introduce a cumulative seismic attribute (CATT) that is very close to being scale independent. This is a new type of attribute formed by integrating the seismic trace impedance. We show the CATT attribute applied to synthetic seismic data to quantify the vertical hydrate accumulation, which means that this class of attribute can be readily applied to real seismic data using seismic impedance volumes. Simply speaking, our approach is to admit that we cannot quantify a reservoir property at a sub-resolution scale. Instead, we quantify the volume integral of this property (or the cumulative property) and introduce a new class of seismic attributes, the cumulative attributes that can be related by means of rock physics to the cumulative reservoir property, which in this specific example is the accumulated volume of methane hydrate. A rock physics transform that connects the gas hydrate saturation in sediment to the elastic-wave velocity still remains the cornerstone of our approach. It is based on the Dvorkin and Nur (1996) effective-medium model which relates the elastic moduli of soft unconsolidated clastic sediment to the porosity, pore fluid compressibility, mineralogy, and effective pressure. 11250 Delineation of gas hydrate-bearing sediments by multi seismic attributes using 3D seismic survey in the eastern Nankai Trough area 8th Society of Exploration Geophysicists of Japan Internationl Symposium 2006/11/26-28 Takao Inamori, Tatsuo Saeki(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team ［Abstract］Bottom Simulating Reflectors (BSRs) were widely found on the marine seismic data acquired offshore Japan, especially in the shelf slope around the eastern Nankai Trough area since 1970’s (for example, Aoki et al., 1983; Shimizu and Tanaka, 2002). In 2000, the occurrence of gas hydrates was confirmed by core and borehole log data In the eastern Nankai Trough area. It gave us so big impact to the view of Japanese future energy resources and other scientific interests. METI, Ministry of Economy, Trade and Industry of JAPAN, started ‘Japan’s Methane Hydrate Exploration Program’ since the autumn of 2001. METI conducted the 3D seismic survey in this area in 2002 and decided well sites and drilled thirty-two boreholes in 2004. Several logs and cores showed the occurrence of gas hydrate. There are several wells found over 30 m gas hydrate-bearing sediments in the eastern Nankai Trough area. We have found the relationship between the occurrence of gas hydrates and BSRs is complicated and the gas hydrate-bearing sediments are inhomogeneous. Gas hydrates are included in the pore-space sediments bearing the sand layer of turbidite channel or lobe mainly. When we will explore and exploit the gas hydrate, we have to get the information of gas hydrate-bearing sediments, such as its saturation, porosity or their thickness. BSRs indicate the existence of gas hydrates. However, we cannot estimate detail reservoir information from BSRs distribution. To estimate the amount of gas hydrates accurately, we need to get the more detailed reservoir parameters from seismic data. We apply the seismic attributes analysis to 3D seismic survey data to delineate hydrate-bearing sediments. We calculate seismic attributes of the P-interval velocity using the dense NMO velocity analysis, P-impedance, S-impedance, and Poisson’s ratio change from pre-stack (AVO) analysis and the attenuation from post-stack analysis. And we delineate of gas hydrate bearing-zones at borehole locations. High P-interval velocity, High P & S impedance, low Poisson’s ratio and high-attenuated layers correspond to the hydrate bearing-zones. We propose the model of gas hydrate-bearing sediments from the analysis of the seismic attributes analysis. 11247 Development a Highly-Active DME Steam Reforming Catalyst for Fuel Cell 2006 Fuel Cell Seminar 2006/11/14-17 Tetsuya Takemoto, Susumu Takami(Osaka Gas), Kenji Nakamura, Kengo Tsukahara(Mitsubishi Gas Chemical), Shinichi Suzuki(Japan Oil, Gas and Metals National Corporatio Research Project Team on Emerging Gas Technologies ［Abstract］Development a Highly-Active DME Steam Reforming Catalyst for Fuel Cell 11246 Development of DME Autothermal Reforming System for Fuel Cell vehicles 2006 Fuel Cell Seminar 2006/11/14-17 Naohiko Matsuda(Mitsubishi Heavy Industries), Shinichi Suzuki(Japan Oil, Gas and Metals National Corporation) Research Project Team on Emerging Gas Technologies ［Abstract］Development of DME Autothermal Reforming System for Fuel Cell vehicles 11244 Research study for Microbial Restoration of Methane Deposit with Subsurface CO2 Sequestration into Depleted Gas/Oil Fields SPE Asia Pacific Oil & Gas Conference and Exhibition 2006/11/11-13 Haruo Maeda(Teikoku Oil),Kazuhiro Fujiwara(Chugai Technos),Komei Okatsu(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Team ［Abstract］Natural gas (methane) is an environmentally excellent form of energy and also one of the most desired energy sources in comparison with the other fossil fuels. On the other hand, the subsurface CO2 disposal and storage technologies could become a “must” in the course of the next century in order to reduce the emissions of green house gases into the atmosphere. This paper presents the result of applicability investigation for microbial restoration of methane deposit using subsurface sequestered CO2 and indigenous microbes in the depleted oil and gas fields in Japan. The important factors are efficiency and velocity of methane generation by indigenous microbes. Fluid samples (producing oil and water) from 3 gas and 2 oil fields in Japan were collected and analyzed in order to find out that the indigenous methane and hydrogen generating microbes were existing under severe (high temperature and high pressure) reservoir conditions. As a result of detail PCR-DGGE and Real Time PCR quantitative analysis, in the samples from two depleted oil fields, very active and high concentrated methane and hydrogen generating microbes were detected. After getting these positive evidence, methane generating experiments were carried out using glucose as a carbon source to estimate the ability of microbial methane generation both in cylinder bottle and core holder (setting berea core inside the holder) under reservoir conditions (5MPa,70 C)). These results indicate that the microbial methane generating efficiency is more dominant in the porous media (suggest active microbes are adsorbed on the surface of rock pore) than in a pool condition (means active microbes are flowing in the water). Judging from these research results, depleted oil reservoir has a possibility to become good candidates as subsurface microbial reactors to convert injected CO2 into methane by using indigenous microbes if suitable and economical carbon source is available. 11243 Direct Synthesis of Dimethyl Ether from Synthesis Gas 8th International Symposium on Biotechnology, Metal Complexes, and Catalysis (BMC-VIII) 2006/11/6 Kaoru Takeishi(Shizuoka Univ.) Research Project Team on Emerging Gas Technologies ［Abstract］Copper alumina catalysts prepared by a sol-gel method that is appropriate for DME steam reforming are applied for the DME direct synthesis (3H2 + 3CO → CH3OCH3 + 2CO2) that is similar reaction of DME steam reforming (CH3OCH3 + 3H2O → 3H2 + 2CO2). Much amount of DME was produced over Cu-Zn(36-4wt.%)/Al2O3 catalyst prepared by the sol-gel method, at 250 ℃ and the lower reaction temperature. The less amount of DME was produced over the mixed catalyst of the methanol synthesis catalyst (N211) and the methanol dehydration catalyst (BK-105), at 310 ℃ and the higher reaction temperature. The single type catalyst that has copper sites for methanol synthesis and alumina sites for methanol dehydration on the surface is more appropriate and more excellent for DME direct synthesis than the mixed catalyst that is one of the patent catalysts for DME direct synthesis. 11240 Hydrogen production by steam reforming of dimethyl ether over single type copper alumina catalysts 3rd Asian DME Conference 2006/10/19 Kaoru Takeishi(Shizuoka Univ.) Research Project Team on Emerging Gas Technologies ［Abstract］It is expected that fuel cell is one of the methods for restraint of the global green effect. Dimethyl ether (DME) dose not contain the poisonous substances, and it burns with no particulate matters (PM), no SOx, and less NOx. DME is expected as a clean fuel of the next generation. DME is able to take the place of light oil and LPG, and its physical properties are similar to those of LPG. There is possibility that DME infrastructures will be settled more rapidly than those of hydrogen and methanol, because LPG infrastructures existing are able to use for DME. Then, we have been studying on steam reforming of DME for the hydrogen production. The results of steam reforming of DME over several catalysts suggested following facts. H2 production with steam reforming of DME consists of two steps. The first step is hydrolysis of DME into methanol. The second step is steam reforming of methanol that produces H2 and CO2. The rate determining step is hydrolysis of DME into methanol. The copper alumina catalysts prepared by the sol-gel method are excellent for H2 production by steam reforming of DME. The reason is that -Al2O3 for the hydrolysis and Cu for methanol-steam reforming are co-existing closely on the catalyst surface. The consecutive reactions smoothly occur. Addition of Zn, Mn, or Fe into Cu(30wt.%)/Al2O3 activates steam reforming of DME. The Cu-Zn(29-1wt.%)/Al2O3 catalyst showed the excellent activity of DME steam reforming; the DME conversion was 95%, H2 yield was 95%, and CO concentration was 0.8 mol.%. We have developed a new catalyst for H2 production from DME, and the catalyst give us a great potential for H2 supply from DME. 11238 Time-Lapse Seismic Survey in the Oil Sands Area 8th SEGJ International Symposium 2006/11/26-28 Toru Nakayama, Akihisa Takahashi(JAPEX), Hisako Mochinaga(Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Team ［Abstract］Time-lapse 3D seismic survey was conducted in the Japan Canada Oil Sands Limited (JACOS) Hangingstone steam-assisted gravity drainage (SAGD) operation area, Alberta, Canada. The objectives of the time-lapse survey were to delineate steam chambers and monitor their growth. A seismic modeling study based on well logs was also carried out to predict the changes in seismic response of the oil sands reservoir due to steam injection. The results of our seismic modeling indicate that the change of the reservoir P-wave velocity due to the steam injection is seismically detectable, and our time-lapse seismic data was consistent with the seismic modeling. The time lapse seismic monitoring is expected to help better understanding of the heterogeneity of the reservoir　sands by integrating the information of the steam chamber geometry and the seismic response analysis. 11232 Understandings of seafloor manifestations utilized by 3D seismic data around the Tenryu knolls in the Nanki Trough 5th Internationl Workshop on Methane Hydrate Research and Development 2006/10/9-12 Sadao Nagakubo,Toshiaki Kobayashi(Japan Oil, Gas and Metals National Corporation), Manabu Tanahashi(AIST), Tetsuya Fujii(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team [Abstract] Understandings of seafloor manifestations utilized by 3D seismic data around the Tenryu knolls in the Nanki Trough 11228 Development of X-ray CT coreflood system for high temperature condition 2nd　International Workshop on X-Ray CT for GEOMATERIALS - GeoX 2006/10/6 Hiroshi Okabe, Yoshihiro Tsuchiya, Kazuhito Oseto, Komei Okatsu(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Team [Abstract] In-situ saturation monitoring with X-ray CT scanners for coreflood experiments gives significant insights into understanding of the fluid flow behaviour especially for heterogeneous rocks. Medical X-ray CT scanners, however, have a limitation for high temperature experiments since the temperature affects the electrical circuit in the system. To overcome the problem, the X-ray CT coreflood system with special heating units has been developed for the experiments under high temperature reservoir conditions. It consists of special line and rubber heaters that accurately control the temperature and does not affect in-situ monitoring. The system allows us to measure petrophysical properties under reservoir conditions including the use of live oil. Advantages of the development for the use of the conventional medical X-ray CT scanner are discussed. 11223 Sequence Stratigraphy and Depositional Facies of the Upper Kharaib Oil Reservoir, offshore Abu Dhabi 17th International Sedimentological Congress 2006/8/28 Osamu Himeno(Japan Oil, Gas and Metals National Corporation), Hidenori Obara(ZADCO), C.Robertson Handford(Strat-Search), Koji Muramoto(JE Oil Exploration) Research Project Team on Subsurface Technologies for Field Development [Abstract] Over the past decades, new technologies for analyzing and visualizing reservoirs have emerged and these have encouraged updating reservoir models. For example, high-resolution sequence stratigraphy is increasingly used as a methodology for providing more accurate reservoir layering schemes and more realistic depositional facies distribution that has not been depicted by litho- stratigraphic correlation. The study area is located approximately 80km northwest of offshore Abu Dhabi. The areal extent of the reservoir reaches 50x30km and a total oil column height of multi-layered reservoirs is over 300m in thickness. In this giant reservoir, heterogeneous water breakthrough has been observed from some wells under the five-spot water injection pattern. The Upper Kharaib reservoir, one of the main reservoir in the field contains high permeability layers and these layers might act as conduits of injected water [1]. It has been difficult to predict the distribution of high permeability layers because of reservoir heterogeneity. To improve the understanding of non-uniform water injection performances and to build a realistic geologic model, it is essentially important to examine depositional facies and stratigraphic architecture of the reservoir. On the basis of detailed rock observation and sequence stratigraphic interpretation for 23 cored-wells located widely in the field, we defined 15 lithofacies and identified five high-frequency (4th-5th order) depositional sequences for the reservoir interval. Lithofacies were grouped into following four major facies associations (FAs), which generally occure in ascending order; Orbitolinid- dominated FA, Lithocodium-dominated FA, Rudist-dominated FA and Miliolid-dominated FA. General depositional environment was interpreted as a leeward carbonate ramp setting gently deepens towards west, extending from orbitolinid-dominated outer ramp, storm-influenced Lithocodium banks in the middle ramp, and inner ramp system with rudist shoals, biostromes, and miliolid grain flats. The five high-frequency depositional sequences (HFS1 to 5) framed by sequence boundaries (SB1 to 6) and maximum flooding surfaces (MFS1 to 5) were identified as a result of stacking pattern analysis (vertical transition in textures and facies successions). These boundaries and surfaces were correlated over the field including non-cored wells. Accordingly, depositional models were constructed for each systems tract based on combined interpretation of core facies and isopach maps. High permeablity layers commonly associated with Bacinella/Lithocodium rudstones deposited under a strong influence of storms. These rudstone layers, which pinch-out within four kms or less, were interpreted to show channels or splay-like distributions deposited in the localized topographic low area of a slight sea floor fluctuation. 11222 ASPHALTENE INDUCED FORMATION DAMAGE: EFFECT OF ASPHALTENE PARTICLE SIZE AND CORE PERMEABILITY International Energy Agency Collaborative Project on Enhanced oil Recovery 2006/9/21 S.S.K.Sim,　D.Fisher（Alberta Research Council）,　 Katsumo Takabayashi,　 Komei Okatsu(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Team [Abstract] The precipitation of asphaltene during CO2 miscible flooding can lead to production losses and reduced efficiencies. Having a clear understanding of the asphaltene deposition mechanism can help the oil industry to develop effective engineering practice to minimize asphaltene deposition and develop treatment program to restore well productivity. This paper presents results of phase behavior and core flood tests conducted at reservoir pressure and temperature conditions to identify the dominating factors associated with permeability reduction during CO2 miscible flood of a light oil reservoir. Initially, dynamic phase behavior of crude oil and CO2 mixtures were investigated to determine the threshold concentration of CO2 required to initiate asphaltene precipitation. The relationship between CO2 concentration and the mass of deposited asphaltene particles were quantified by analyzing the images of the mixtures as well as by physical separation of the deposited asphaltene solids. Laboratory core flood tests were conducted to investigate the effect of asphaltene deposition in reduction of core permeability. Variables investigated included, initial core permeability, CO2 concentration and quantity and size of asphaltene particles presence in the oil/CO2 mixtures. Porous media used included sandpack, reservoir carbonate cores and commercial Indiana limestones. The tests were conducted at 100 ℃ and 3000 psig with reservoir crude oil containing CO2 concentration in the range of 40-70 mol%. Phase behaviour results indicated that the mass and particles size of asphaltene particles precipitated from the mixtures was strongly dependent on the CO2 concentration. Core flood test results showed that the severity of formation damage was related to the initial core permeability as well as the quantity and size of the asphaltene particles precipitated. The damage mechanism was found analogous to the 1/3 and 1/7 rule of thumb that relate the size of particulates in injected water to potential permeability reduction. It was also observed that formation damage caused by shallow solid invasion was more readily removed by crude oil injection while remediation of formation damage caused by deep solid invasion, was more difficult. 11221 Effects of pore structures on the fluid flow examined by the lattice-Boltzmann method International Energy Agency Collaborative Project on Enhanced Oil Recovery 2006/9/21 Hiroshi Okabe(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Team [Abstract] Recent developments of the microtomography and the pore-network model have been successful and brought predictive capabilities for multiphase flow at the pore-scale. However, some of the issues such as complicated pore structures with heterogeneous wettability distributions in the mixed-wet porous media, especially for carbonates, have not been solved yet and the wettability distribution is still one of the parameters that can significantly control the flow behavior at the pore-scale. The lattice-Boltzmann method (LBM) to simulate multiphase flow at the pore-scale is used in the study in order to assess the effects of pore structures on the fluid flows. The LBM provides a good approximation to solutions of the Navier-Stokes equations using a parallel and efficient algorithm that readily accommodates complex boundaries such as porous media. Simple and elemental structures such as divergent and convergent flows are used to evaluate the relations between pore structures and multiphase flows using the LBM. The fundamental study at the simple pore structure can give us the significant insight to implement the pore-network model and to improve the understanding of fluid flow in the reservoir. 11220 High Pressure Air Injection into Light Oil Reservoirs: Sensitivity Study for Vertical Sweep Performance International Energy Agency Collaborative Project on Enhanced Oil Recovery 2006/9/22 Takeshi Onishi (Japan Oil, Gas and Metals National Corporation),　 Hiroshi Uematsu(Teikoku Oil),　 Komei Okatsu (Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Team [Abstract] Recently, High Pressure Air Injection (HPAI) to light oil reservoirs is considered to be an effective EOR method. HPAI has some remarkable merits as follows. (1) Injection gas source is air, which can be supplied anywhere. (2) Initial and operation costs are inexpensive because the main facility required is only air compressor and air is free. (3) Air can be applied even in low permeable reservoirs where water cannot be injected. On the other hand, the evaluation method for HPAI is quite difficult, because oxidation and combustion reactions are complicated. HPAI research mainly consists of experiments and numerical simulation. A series of experiments is essential to evaluate potential of HPAI in fields, such as Accelerating Rate Calorimeter test, Thermo Gravimetric Pressurized Differential Scanning Calorimeter test and Combustion Tube (CT) test. Especially, CT test is important because the test is physical simulation of HPAI. Numerical simulation is also important to predict field production performance. The appropriate reaction kinetics used in the simulation model has the key to the expression of the real chemical reactions. History matching with CT test is the only way to obtain the kinetics. The good results have been already obtained in history matching. The next step is field-scale simulation using the kinetics obtained in the matching. Field test of air injection is examined in a certain field. The field has highly water saturated light oil reservoir, because of strong water drive mechanism. High dip is also existed. The actual data of field property is limited. This paper describes numerical simulation study using thermal simulator to investigate the sensitivity for vertical sweep performance. The reservoir properties in the model come from the field. The model has two dimensional and field-scale grid size. The parameters to be investigated are dip, perforation intervals of production well, permeability, temperature of air injected and so forth. Based on the results, it is concluded that some parameters is critical and others are non-critical to the oil recovery. The examples of results are shown as follows. When recoveries from no dip and high dip reservoirs are compared, the recovery is higher in the latter case. Production well should be perforated only at lower zone to obtain higher oil recovery. In addition, the ultimate oil recovery is observed to be insensitive to the temperature of air injected. 11217 Pore-scale heterogeneity assessed by the lattice-Boltzmann method International Symposium of the Society of Core Analysis 2006/9/14 Hiroshi Okabe,Kazuhito Oseto(Japan Oil, Gas and Metals National Corporation) Petroleum Engineering Research Team [Abstract] A digital imaging technique is used to characterize pore-scale structures and to predict fluid flow at the scale. Heterogeneity at the pore-scale can be assessed by the micro-Computed Tomography (micro-CT), which provides complicated boundary conditions of porous media, and it can also be identified by the numerical flow simulation using the lattice-Boltzmann method (LBM) on the digital image. Both the LBM and the digital image are used to estimate the Representative Element Volume (REV) of the rock. Different types and sizes of pore-scale structures are evaluated in terms of the effects of heterogeneity and the porosity-permeability correlations. Numerical simulation on the digital image of porous media is useful to understand its heterogeneity and such digital experiments can add value to the laboratory measurements. 11214 Hydrogen production by steam reforming of dimethyl ether over single type copper alumina catalysts prepared by a sol-gel method The 232nd ACS National Meeting 2006/9/13 Kaoru Takeishi(Shizuoka Univ.) Research Project Team on Emerging Gas Technologies ［Abstract］Dimethyl ether (DME) is expected as a clean fuel of the next generation. DME has recently become a potential fuel for hydrogen production to be used in fuel cells. There is possibility that DME infrastructures will be settled more rapidly than hydrogen, because LPG infrastructures existing are able to be used for DME. I have developed Cu-Zn/Al2O3 catalysts prepared by a sol-gel method for hydrogen production by DME steam reforming. The catalysts produce hydrogen more effectively than mixed catalysts with DME hydrolysis catalysts and methanol steam reforming catalysts. SEM-EDS analyses have suggested that the Cu-Zn/Al2O3 catalysts have the catalyst surface structure that is appropriate for the steam reforming of DME consisting of DME hydrolysis and methanol steam reforming. Experiments on the effect of the space velocity, durability test, and other experiments have suggested that the further developments are still need but the catalysts have enough capability for practical use. 11212 Seismic facies-guided geomorphological analysis of submarine-fan shape variation using 3D seismic data 17th International Sedimentological Congress 2006/9/1 Osamu Takano,Mizue Nishimura,Ayato Kato,Tatsuo Saeki(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team [Abstract] Seismic facies-guided geomorphological analysis of submarine-fan shape variation using 3D seismic data 11211 Quaternary carbonates around the Ryukyu Islands - sedimentary facies and sea level changes - 17th International Sedimentological Congress 2006/8/30 Yoshihiro Tsuji(Japan Oil, Gas and Metals National Corporation), Yasufumi Iryu(Tohoku Univ.), Kaoru Sugihara(Fukuoka Univ.), Hiroki Matsuda(Kumamoto Univ.) Geology & Geophysics Research Team [Abstract] Quaternary carbonate deposits comprising reefal and deeper water facies, occur around the Ryukyu Islands, southwestern Japan. The reefs consist of coralliferous limestone in which more than 100 species of hermatypic corals are recognized, and deeper water facies consist of rhodoliths and larger foraminifera limestones. The contents of this short course will be (1) Introductory lectures on present-day and Quaternary carbonates around the Ryukyu Islands, (2) Observations of marine sediments and core samples, as well as thin sections, and (3) Sedimentological analyses of the carbonate succession and palaeontological examination of fossil assemblages for reconstructing sea-level changes. This short course is intended to provide a facies model applicable to Cenozoic. 11210 230Th/234U and 14C dating of submerged coral reefs on the insular shelf off Irabu Island, Ryukyus, southwestern Japan 17th International Sedimentological Congress 2006/8/28-29 Keiichi Sasaki(Kanazawa Gakuin Univ.), Akio Omura,Nobuyuki Kuroiwa, Kenji Konishi(Kanazawa Univ.), Hiroki Matsuda(Kumamoto Univ.)Yoshihiro Tsuji(Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Team [Abstract] The Technology Research Center, Japan National Oil Corporation (JNOC-TRC: presently Technology and Research Center, Japan Oil, Gas and Metals National Corporation) surveyed detailed topography and surface carbonate sediments and recovered four offshore drilling cores in the insular shelf around Irabu Island, Southern Ryukyus of Japan in a research project entitled ‘Techniques for Reconstruction and Interpretation of Reservoir Developments.’ The insular shelf can be morphologically subdivided into inner and outer shelves at about 50-55 m depth. Number of pinnacles, ~1 km in diameter and 10-40 m in height, are distributed in the inner shelf. Two drill cores, CR8 and 9, revealed these pinnacles to be submerged coral reefs. We report lithology with fossil coral assemblages and radiometric age data of these cores and discuss about growth patterns of reefs responding to rapid sea level rise since the last glacial maximum. Cores were drilled at sites CR8 (24°43’23”N, 125°10’00”E; -15.5 m) and CR9 (24°41’11”N, 125°07’11”E; -45.5 m). Holocene reefal limestone, unconformably overlying Pleistocene Ryukyu Group, occupied top of each pinnacle with 7.3 and 2.0 m in thickness at CR8 and 9, respectively. Holocene sediments can be lithologically divided into two units in both sites. Lithologic changes show similar pattern in both sites, and indicate deepening-upward trend of depositional environments. Total of 20 corals of CR8 and 9 cores were dated by α-spectrometric 230Th/234U and liquid-scintillation 14C methods. Ages and growth rates of lower units of CR8 and 9 were estimated to be 8.9-7.9 ka with 4.3 m/kyr and 10.5-8.9 ka with 0.7 m/kyr, respectively. Upper units were deposited until the present with low sedimentation rates, 0.4 and 0.1 m/kyr, in CR8 and 9. Both reefs show obvious change in growth rates from the lower units to the upper. Increased water depth of depositional environments and decreased growth rates demonstrate that these submerged reefs were drowned by rapid sea level rise during the last deglaciation after deposition of reef frames dominated by shallow coral species. Thus, Holocene transgressive systems tract is represented by back-steppings of drowned reefs on topographic highs beneath the inner shelf in this area. 11209 Reservoir Properties and Depositional Facies of the Upper Kharaib Carbonate Oil Reservoir, Offshore Abu Dhabi. 17th International Sedimentological Congress 2006/8/28 Toshiaki Shibasaki,Tomohiro Obara(JODCO), Osamu Himeno(Japan Oil, Gas and Metals National Corporation), Hidenori Obara(ZADCO) Research Project Team on Subsurface Technologies for Field Development [Abstract] The upper Kharaib reservoir of the Lower Cretaceous is one of the major oil-producing horizons offshore Abu Dhabi in the United Arab Emirates. The study field is located offshore Abu Dhabi of the Arabian Gulf and the areal extent of the reservoir reaches 50x30kilometers. This carbonate reservoir is characterized by heterogeneous reservoir properties containing thin high permeability layers. They have caused premature water breakthrough that has been observed from some wells under five spot water injection pattern. The preferential water movement due to the reservoir heterogeneity has an impact on the production performance and oil recovery. Therefore, reliable permeability modeling is one of the major key issues. Reservoir properties such as porosity and permeability of carbonate rocks have been susceptible to depositional environments and subsequent diagenesis, and, in general, are more complicated than that of siliciclastic sedimentary rocks. In addition, permeability prediction of carbonate rocks from wire-line log data has not been achieved sufficiently due to the resolution of log data and the complexity of grain types and pore systems with primary and secondary pore networks. Therefore, it is important to identify the main geologic controls on the reservoir properties and to construct reservoir property models, e.g. porosity and permeability models, from geologic concepts. In this carbonate reservoir, depositional aspects, e.g. texture, grain size and sorting, were important to characterize the high permeability rock types [1]. In addition, the grain types and their hardness have an impact on the reservoir quality [2]. The grain types were also related with depositional environments. Based on the detailed core observation, thin section description and sequence stratigraphic interpretation, a new layering scheme and a series of facies distribution models were constructed. Possible high permeability facies such as Bacinella/ Lithocodium rudstones deposited under an influence of storm condition were identified. This paper presents the reservoir properties and geological factors in the newly defined depositional facies. Then a workflow of 3D reservoir properties modeling from 3D depositional models is proposed. 11207 Concentration of Gas Hydrate in Sandy Sediments Relevant to Subsurface Occurrence and Methane Accumulation 17th International Sedimentological Congress 2006/8/27-9/1 Takashi Uchida,Amane Waseda(JAPEX),Takatoshi Namikawa(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team [Abstract] Concentration of Gas Hydrate in Sandy Sediments Relevant to Subsurface Occurrence and Methane Accumulation 11205 Organic Geochemistry of Gas Hydrates and Sediments in the Eastern Nankai Trough,Japan 17th International Sedimentological Congress 2006/8/27-9/1 Amane Waseda,Takashi Uchida(JAPEX),Takatoshi Namikawa(Japan Oil, Gas and Metals National Corporation) Methane Hydrate Research Project Team [Abstract] Organic Geochemistry of Gas Hydrates and Sediments The MH21 has,Japan 11203 3D seismic interpretation of submarine fans in the shallow structure beneath the sea floor in the northern part of the Kumano basin, Japan 17th International Sedimentological Congress 2006/8/27-9/1 Tatsuo Saeki,Takao Inamori(Japan Oil, Gas and Metals National Corporation),　Osamu Takano(JAPEX) Methane Hydrate Research Project Team [Abstract] Aiming commercialization of methane hydrate production to be examined as future energy resources, the Research Consortium for Methane Hydrate Resources in Japan (MH21)has been executing the geological and geophysical survey around the eastern Nankai Trough since 2001. It is very important to delineate the distribution of porous sediments, which can reserve a large amount of gas-hydrates in the methane hydrates exploration as the same as in the conventional petroleum exploration. In offshore deep sea, it generally means that　the　delineation of distributions of submarine-fan turbidite sand bodies should be required. 3D seismic reflection data and visualization software can be powerful tool to image and classify various geological sedimentation patterns of submarine fans including submarine channels and lobes. Detailed 3D seismic interpretation was applied to the northern pat of the Kumano basin, one portion of 3D seismic survey areas around the eastern Nankai Trough. This article introduces the interpreted structure shallower than about 200 mbsf among the full volume interpretation. 11202 High-resolution seismic survey on the Quaternary sediment off Amami-o shima Island, northern Ryukyu Island Arc, Japan 17th International Sedimentological Congress 2006/8/27-9/1 Kohsaku Arai(AIST), Hiroki Matsuda(Kumamoto Univ.), Hideaki Machiyama(JAMSTEC), Yasufumi Iryu(Tohoku Univ.), Yoshihiro Tsuji(Japan Oil, Gas and Metals National Corporation) Geology & Geophysics Research Team [Abstract] High-resolution single channel seismic reflection surveys for the northern Ryukyu Island Arc about 784 km suggested the existence of mound shape reflections within the stratified sedimentary units considerable to be “coral reefs” or banks with coarse- grained bioclasts. The mound shape reflections overlie the acoustic basement or stratified sediment and reach 15 m high and 400 m wide. Some of them occurs uppermost of Quaternary sedimentary unit. Onlapping reflection terminations are recognized at upper boundary on the other one. Northern limit of coral reef formation during lowstand age such as last glacial maximum is discussed. 11201 Pull-up anomalies of the BSR structure in the Kumano Basin Western Pacific Geophysics Meeting 2006/7/24-27 Tatsuo Saeki,Takao Inamori(Japan Oil, Gas and Metals National Corporation),　Sadao Nagakubo(JDC), Sumito Morita(AIST) Methane Hydrate Research Project Team [Abstract] Interpretation of 3D seismic reflection data, which was acquired by METI (Ministry of Economy, Trade and Industry of JAPAN) and reprocessed by MH21 (the Research Consortium for Methane Hydrate Resources in Japan), revealed the detailed BSR structure in the northern rim of the Kumano basin around the eastern Nankai trough, Japan. Conventionally, the BSR (bottom simulating reflector), which is considered to be a bottom of the gas hydrate bearing sediment, has been picked as the reflector in parallel with sea-bottom topography. The interpreted BSR in the Kumano basin include two types of local pull-up phenomenon that had no correlation with the sea- bottom topography. Strictly speaking, above pull-upped reflectors should not be called as BSR because they do not simulate the sea-bottom. However, detected anomalous events were continuous with typical BSR reflectors around them. Most remarkable BSR pull-up phenomena occurred in the small circle area of 400m in diameter and the topography is like a mountain. The center top was closed to the sea-bottom in which the pock mark existed. Another type anomaly consisted of several small pull-ups distributed in a line. Seismic velocity analysis showed that there were local high velocity anomalies directly above them, which could cause apparent BSR pull-ups. The geological interpretation suggested the possibility that above high velocities occurred due to concentrations of gas hydrate. On the other hand, the mountain type BSR pull-up might be related with the local variation of the thermal condition. BACK 1 2 3 4 5 6 7 NEXT

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