Characteristics of Oil and Gas Accumulation in Yong'an-Meitai Area of the Fushan Depression,Beibuwan Basin,South China Sea

作     者：Li Meijun Wang Tieguan Liu Ju Zhang Meizhu Lu Hong Ma Qinglin Gao Lihui 

作者机构：Key Laboratory for Hydrocarbon Accumulation Mechanism Ministry of Education School of Resources and lnformation China University of Petroleum Beo＇ing 102249 China South Oil Exploration and Development Company PetroChina Guangzhou Guangdong 510240 China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou Guangdong 510640 China 

出 版 物：《Petroleum Science》 (石油科学（英文版）)

年 卷 期：2007年第4卷第4期

页      面：23-33页

核心收录：

学科分类：0820[工学-石油与天然气工程] 08[工学] 082002[工学-油气田开发工程] 

基　　金：This research was financially supported by the Natural Science Foundation of China(Grant No.40672093) CNPC Innovation Fund(07El001) the ESS-China Hydrocarborn Geoscience Collaboration Project under Natural Resources Canada's International 0pportunities Program.We extend our thanks to South 0il Exploration and Development Company of PetroChina for samples collection 

主　　题：Reservoir geochemistry homogenization temperature burial and thermal history oil migration and accumulation the Fushan Depression 

摘      要：The Yong＇an-Meitai area is the focus of the present exploration in the Fushan Depression, Beibuwan Basin, South China Sea. All oils from this area are geochemically characterized by higher Pr/Ph ratio, higher proportion of heavy molecular weight hydrocarbons, and higher proportion of C29 regular steranes, which indicate that the organic matter of source rocks might have been deposited in an oxidizing palaeoenvironment and be dominated by higher plant organic matter input. The oil from E3w2 （the second member of Weizhou Fro. of the Oligocene） has a much higher density, relatively higher Pr/nC17 and Ph/nC18 ratios, and a ＂UCM--unresolved complex mixture＂ on gas chromatograms, which indicate that it has been slightly biodegraded. CPI and other terpane and sterane isomer ratios suggest they are all mature oils. The timing of oil charging in E3w2 and E2I1 （the first member of the Liushagang Fro. of the Eocene） determined by the homogenization temperatures of fluid inclusions and thermal evolution history are from 9-3 Ma and 8-3 Ma, respectively. Thus, the interpretation of E3w2 as a secondary reservoir is unlikely. The timing of oil charging is later than that of hydrocarbon generating and expulsion of Liushagang Fin. source rocks and trap formation, which is favorable for oil accumulation in this area. All molecular parameters that are used for tracing oil filling direction decrease with shallower burial depth, which suggests vertical oil migration. The widely occurring faults that penetrate through the source rocks of the Liushagang Fro. may serve as a fine oil charging conduit.