Influence of seafloor topography on gas hydrate occurrence across a submarine canyon-incised continental slope in the northern margin of the south china sea

doi:10.1016/j.marpetgeo.2021.105279

CORC > 深海科学与工程研究所 > 中国科学院深海科学与工程研究所 > 深海科学研究部 > 深海地球物理与资源研究室

	Influence of seafloor topography on gas hydrate occurrence across a submarine canyon-incised continental slope in the northern margin of the south china sea
	Wang, Jiliang 1,5; Wu, Shiguo 1,5; Sun, Jin 5; Feng, Wanli 2,5; Li, Qingping 3,4
刊名	MARINE AND PETROLEUM GEOLOGY
	2021-11-01
卷号	133 页码:19
关键词	Gas hydrate stability zone Geothermal gradient Bottom simulating reflection Topographic effect South China Sea
ISSN号	0264-8172
DOI	10.1016/j.marpetgeo.2021.105279
英文摘要	In a submarine canyon-incised continental slope, the observed bottom simulation reflection (BSR) frequently appears not to match with the predicted base of the gas hydrate stability zone (BGHSZ). However, the mechanism behind this discrepancy is often debated due to the lack of in-situ borehole measurements. In the Shenhu area, a submarine canyon region on the northern continental slope of the South China Sea, a suite of datasets, including 3D seismic data, well logs and in-situ borehole temperature measurements enable us to study the gas hydrate stability zone. In-situ borehole temperature measurements reveal a nonlinear geothermal gradient within shallow 200 m-thick marine sediments. The geothermal gradient fit with the uppermost sediment interval (<50 m) neglected produces a better match between the depths of predicted BGHSZ and observed BSR. The gas hydrate stability zone (GHSZ) modeling using in-situ borehole measurement information at Site W07 shows that the predicted BGHSZ agrees well with the imaged BSR located atop an inter-canyon ridge, demonstrating that the gas hydrate system is in a steady state. Two-dimensional GHSZ modeling along seismic profiles transecting the ridge shows that the observed BSRs along the western margin of the ridge are deeper than the predicted BGHSZ. We interpret this apparent discrepancy to be attributed to topographic effects. Two scales of topographic effects, i.e. an alternating distribution of canyons and inter-canyon ridges, and localized crests and troughs over the crest of inter-canyon ridges, are revealed to influence gas hydrate system in the study area. The curved BGHSZ resulted from the topographic effect could facilitate the concentration of gas hydrate by enlarging the accumulation space and sealing free gas immediately below BGHSZ.
资助项目	Youth Innovation Promotion Association, Chinese Academy of Sciences[2019360] ; National Key Research and Development Program of China[2018YFC0310105] ; National Key Research and Development Program of China[2019YFC0312301] ; Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)[311021003]
WOS关键词	SEISMIC DATA ; SHENHU AREA ; FLUID-FLOW ; HEAT-FLOW ; OFFSHORE ; RESERVOIR ; SYSTEMS ; BENEATH ; ESCAPE ; RIDGE
WOS研究方向	Geology
语种	英语
出版者	ELSEVIER SCI LTD
WOS记录号	WOS:000702878500003
资助机构	Youth Innovation Promotion Association, Chinese Academy of Sciences ; National Key Research and Development Program of China ; Innovation Group Project of Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)
内容类型	期刊论文
源URL	[http://ir.idsse.ac.cn/handle/183446/8859]
专题	深海科学研究部_深海地球物理与资源研究室
通讯作者	Wang, Jiliang
作者单位	1.Southern Marine Sci & Engn Guangdong Lab Zhuhai, Zhuhai 519080, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.State Key Lab Nat Gas Hydrate, Beijing 100027, Peoples R China 4.CNOOC Res Inst Co Ltd, Beijing 100027, Peoples R China 5.Chinese Acad Sci, Inst Deep Sea Sci & Engn, Sanya 572000, Peoples R China
推荐引用方式 GB/T 7714	Wang, Jiliang,Wu, Shiguo,Sun, Jin,et al. Influence of seafloor topography on gas hydrate occurrence across a submarine canyon-incised continental slope in the northern margin of the south china sea[J]. MARINE AND PETROLEUM GEOLOGY,2021,133:19.
APA	Wang, Jiliang,Wu, Shiguo,Sun, Jin,Feng, Wanli,&Li, Qingping.(2021).Influence of seafloor topography on gas hydrate occurrence across a submarine canyon-incised continental slope in the northern margin of the south china sea.MARINE AND PETROLEUM GEOLOGY,133,19.
MLA	Wang, Jiliang,et al."Influence of seafloor topography on gas hydrate occurrence across a submarine canyon-incised continental slope in the northern margin of the south china sea".MARINE AND PETROLEUM GEOLOGY 133(2021):19.