HR: 1340h
AN: OS23A-1049    [Abstracts]
TI: Methane hydrate reservoir model around the Eastern Nankai Trough area offshore Japan
AU: * Inamori, T
EM: inamori-takao@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AU: Hayashi, M
EM: hayashi-masao@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AU: Kobayashi, T
EM: kobayashi-toshiaki@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AU: Shimoda, N
EM: shimoda-naoyuki@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AU: Takano, O
EM: takano-osamu@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AU: Takayama, T
EM: takayama-tokujiro@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AU: Fujii, T
EM: fujii-tetuya@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AU: Nagakubo, S
EM: nagakubo-sadao@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AU: Saeki, T
EM: saeki-tatsuo@jogmec.go.jp
AF: JOGMEC, 1-2-2, Hamada, Mihama-ku, Chiba, 2610025, Japan
AB: 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 reviewed 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.
DE: 3000 MARINE GEOLOGY AND GEOPHYSICS
DE: 3004 Gas and hydrate systems
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting