摘要
琼东南盆地深水区天然气水合物富集条件优越,具有巨大的勘探开发前景。基于近年来新获取的海洋地质地球物理关键参数,反演了琼东南盆地深水区上新世(约5 Ma)以来的天然气水合物稳定域迁移过程。研究表明:琼东南盆地现今天然气水合物稳定域主要存在于水深>600 m的海底,约在水深1800~2400 m处水合物稳定域厚度达到最大值,约190 m;冰期海平面下降导致水合物稳定域向深海平原迁移,而陆坡-深海平原转换带的水合物稳定域厚度则相对于现今减薄约80 m;岩浆热事件导致深海平原水合物稳定域厚度减薄约50 m,天然气水合物随之分解后释放大量气体导致多边形断层形成。
The deepwater area of the Qiongdongnan Basin is beneficial to the enrichment of natural gas hydrate,where great potential occurs for commercial exploration and development of the hydrate.Utilizing the key parameters obtained in recent years,the dynamic migration of gas hydrate stability zone in the deepwater area of the basin since Pliocene(approximate 5 Ma)is carefully studied in this paper.The results suggest that the gas hydrate stability zone in the Qiongdongnan Basin currently occurs under the seafloor with a water depth>600 m and the maximum thickness may approach 190 m in the area with water depths around 800~2400 m.Sea level falling during the glacial period might drive the gas hydrate stability zone migrating toward the abyssal plain,and there was an approximately 80 m reduction of gas hydrate stability zone in the transitional zone between the continental slope and abyssal plain.Thickness of the gas hydrate stability zone in the abyssal plain was thinned by approximately 50 m due to magmatic thermal events,and hydrate decomposition may cause the formation of polygonal faults.
作者
江定川
刘睿
赵晓明
方小宇
葛家旺
陆江
姚哲
朱继田
宋鹏
JIANG Dingchuan;LIU Rui;ZHAO Xiaoming;FANG Xiaoyu;GE Jiawang;LU Jiang;YAO Zhe;ZHU Jitian;SONG Peng(Guangdong Laboratory of Southern Marine Science and Engineering-Zhaiijiang,Zhanjiang 524000,China;School of Geoscience and Technology,Southwest Petroleum University,Chengdu 610500,China;Zhanjiang Branch of CNOOC Limited,Zhanjiang 524057,China)
出处
《海洋地质前沿》
CSCD
北大核心
2021年第7期43-51,共9页
Marine Geology Frontiers
基金
南方海洋科学与工程广东省实验室(湛江)“南海水合物富集规律及固态流化开采机理研究(一期)”(ZJW-2019-03)
国家自然科学基金(42072184,41702157)。
