Downward shift of gas hydrate stability zone due to seafloor erosion in the eastern Dongsha Island,South China Sea  

作　　者：JIN Jiapeng WANG Xiujuan HE Min LI Jie YAN Chengzhi LI Yuanping ZHOU Jilin QIAN Jin 

机构地区：[1]Key Laboratory of Marine Geology and Environment&Center of Deep-Sea Research,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China [2]Laboratory for Marine Mineral Resources,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266071,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Center for Ocean Mega-Science,Chinese Academy of Sciences,Qingdao 266071,China [5]Shenzhen Branch of China National Offshore Oil Corporation Ltd,Shenzhen 518054,China

出　　处：《Journal of Oceanology and Limnology》2020年第4期1188-1200,共13页海洋湖沼学报（英文）

基　　金：the National Key R&D Program of China(No.2017YFC0307301-1);the National Natural Science Foundation of China(No.41676041);the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0104);the National High Technology Research and Development Program of China(863 Program)(No.2013AA092601)。

摘　　要：New acquired and reprocessed three-dimensional(3D)seismic data were used to delineate the distribution and characterization of bottom simulating reflections(BSRs)in the Chaoshan Sag,in the eastern part of Dongsha Island,South China Sea.Three submarine canyons with different scales were interpreted from the 3D seismic data,displaying three stages of canyon development and are related with the variation of BSR.Abundant faults were identified from the coherence and ant-tracing attributions extracted from 3D seismic data,which provide the evidence for fluid migration from deeper sediments to the gas hydrate stability zone(GHSZ).The uplift of Dongsha Island created a large number of faults and leads to the increased seafloor erosion.The erosion caused the cooling of the seafloor sediments and deepening of the base of the gas hydrate stability zone,which is attributed to the presence of paleo-BSR and BSR downward shift in the study area.Hence,methane gas may be released during the BSR resetting and gas hydrate dissociation related with seafloor erosion.

关 键 词：bottom simulating reflections(BSRs) downward shift seafloor erosion gas hydrate dissociation 

分 类 号：P618.13[天文地球—矿床学] P631.46[天文地球—地质学]