Deep-large faults controlling on the distribution of the venting gas hydrate system in the middle of the Qiongdongnan Basin, South China Sea  

作　　者：Jin-feng Ren Hai-jun Qiu Zeng-gui Kuang Ting-wei Li Yu-lin He Meng-jie Xu Xiao-xue Wang Hong-fei Lai Jin Liang 

机构地区：[1]National Engineering Research Center of Gas Hydrate Exploration and Development,Guangzhou 511458,China [2]Guangzhou Marine Geological Survey,China Geological Survey,Guangzhou 511458,China [3]China Geological Survey,Ministtry of Natural Resources,Beijing 100037,China

出　　处：《China Geology》2024年第1期36-50,共15页中国地质（英文）

基　　金：supported by the National Natural Science Foundation of China(42376221,42276083);Director Research Fund Project of Guangzhou Marine Geological Survey(2023GMGSJZJJ00030);National Key Research and Development Program of China(2021YFC2800901);Guangdong Major Project of Basic and Applied Basic Research(2020B030103003);the project of the China Geological Survey(DD20230064).

摘　　要：Many locations with concentrated hydrates at vents have confirmed the presence of abundant thermogenic gas in the middle of the Qiongdongnan Basin(QDNB).However,the impact of deep structures on gasbearing fluids migration and gas hydrates distribution in tectonically inactive regions is still unclear.In this study,the authors apply high-resolution 3D seismic and logging while drilling(LWD)data from the middle of the QDNB to investigate the influence of deep-large faults on gas chimneys and preferred gasescape pipes.The findings reveal the following:(1)Two significant deep-large faults,F1 and F2,developed on the edge of the Songnan Low Uplift,control the dominant migration of thermogenic hydrocarbons and determine the initial locations of gas chimneys.(2)The formation of gas chimneys is likely related to fault activation and reactivation.Gas chimney 1 is primarily arises from convergent fluid migration resulting from the intersection of the two faults,while the gas chimney 2 benefits from a steeper fault plane and shorter migration distance of fault F2.(3)Most gas-escape pipes are situated near the apex of the two faults.Their reactivations facilitate free gas flow into the GHSZ and contribute to the formation of fracture‐filling hydrates.

关 键 词：Venting gas hydrates Deep-large faults Gas chimney Gas-escape pipes High-resolution 3D seismic Logging while drilling Qiongdongnan Basin South China Sea 

分 类 号：P618.13[天文地球—矿床学]