Browse > Article

Fusion of 3D seismic exploration and seafloor geochemical survey for methane hydrate exploration  

Nagakubo, Sadao (Japan Oil, Gas and Metals National Corporation)
Kobayashi, Toshiaki (Japan Oil, Gas and Metals National Corporation)
Fujii, Tetsuya (Japan Oil, Gas and Metals National Corporation)
Inamori, Takao (Japan Oil, Gas and Metals National Corporation)
Publication Information
Geophysics and Geophysical Exploration / v.10, no.1, 2007 , pp. 37-43 More about this Journal
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 the 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.
Keywords
BSR; seafloor geochemical survey; high-resolution 3D seismic survey; methane hydrate; Nankai Trough;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Borowski, W. S., Paull, C. K., Ussler, W., III, 1996, Marine porewater sulfate profiles indicate in situ methane flux from underlying gas hydrate: Geology 24, 655-658. doi: 10.1130/0091-7613(1996) 024<0655:MPWSPI>2.3.CO;2   DOI   ScienceOn
2 Tsuji, Y., Nonaka, Y., and METI, 2004, Multi-well drilling campaign METI "Tokai-Oki to Kumano-nada", in 2004 for methane hydrate evaluation in the Nankai Trough, off central Japan.: Gas Hydrates: Energy Resource Potential and Associated Geologic Hazards, AAPG Hedberg Research Conference, Extended Abstracts, 1-2
3 Tsunogai, U., Wakita, H., Ashi, J., Gamo, T., 1997, Fresh water seepage on the seafloor: Ryuyo Canyon, Nankai Trough: JAMSTEC Journal of Deep-Sea Research 13, 503-508
4 Nagakubo, S., Kobayashi, T., and Tanahashi, M., 2006b, Understandings of seafloor manifestations utilized by 3D seismic data around Tenryu knolls: Japan Geoscience Union Meeting 2006, Extended Abstracts, G228-003
5 Ashi, J., Huchon, P., Segawa, J., Thoue, F., Kobayashi, K., 1995, Geological Structure and Cold Seepage at the Prism Slope Depression off Omaezaki: the 1994 KAIKO-TOKAI "Shinkai 2000" Dives: JAMSTEC Journal of Deep-Sea Research 11, 189-195
6 Shimizu, S., Oikawa, N., Hayashi, M., Ochiai, K., and Nakamizu, M., 2003, The results of METI Geophysical explorations in FY2003 and 2004 - Methane Hydrate Exploration: Proceedings of the 109th Conference, The Society of Exploration Geophysicists of Japan, 1-3
7 Nagakubo, S., Kobayashi, T., Inamori, T., and Fujii, T., 2006a, Anomaly of BSR depths at the Ryuyo area in the Eastern Nankai Trough: Japan Geoscience Union Meeting 2006, Extended Abstracts, G228-P001
8 Sassen, R., Losh, S. L., Cathles, L., III, Roberts, H. H., Whelan, J. K., Milkov, A. V., Sweet, S. T., DeFreitas, D. A., 2001, Massive vein-filling gas hydrate: relation to ongoing gas migration from the deep subsurface in the Gulf of Mexico: Marine and Petroleum Geology 18, 551-560. doi: 10.1016/S0264-8172(01)00014-9   DOI   ScienceOn
9 Takahashi, H., and Tsuji, Y., 2005, Multi-Well Exploration Program in 2004 for Natural Hydrate in the Nankai-Trough Offshore Japan: Offshore Technology Conference, 17162
10 Tsunogai, U., Yoshida, N., Gamo, T., 2002, Carbon isotopic evidence of methane oxidation through sulfate reduction in sediment beneath seafloor cold seep vents on the seafloor at Nankai Trough: Marine Geology 187, 145-160. doi: 10.1016/S0025-3227(02)00263-3   DOI   ScienceOn
11 Nagakubo, S., Tanahashi, M., Ikehara, K., Fujii, T., 2005, Geochemical seafloor surveys for exploration of methane hydrates in the eastern Nankai Trough: Chikyu 27, 954-959