A pre-Paleogene unconformity surface of the Sikeshu Sag, Junggar Basin: Lithological, geophysical and geochemical implications for the transportation of hydrocarbons  

作　　者：Xiaoyue Gao Luofu Liu Zhenxue Jiang Xiaoqing Shang Guodong Liu 

机构地区：[1]State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum (Beijing) [2]Basin and Reservoir Research Center,China University of Petroleum (Beijing)

出　　处：《Geoscience Frontiers》2013年第6期779-786,共8页地学前缘（英文版）

基　　金：fnancially supported by the National Key Project of Science and Technology for Development of Large-size Oil&Gas Fields and Coal-bed Gas(Grant No.2008ZX05003-002);by the State Key Laboratory of Petroleum Resources and Prospecting(No.prp2009-02);The study is a contribution to IGCP#592 Project

摘　　要：The unconformity surface at the bottom of the Paleogene is one of the most important migration pathways in the Sikeshu Sag of the Junggar Basin,which consists of three layers：upper coarse clastic rock,lower weathering crust and leached zone.The upper coarse clastic rock is characterized by higher density and lower SDT and gamma-ray logging parameters,while the lower weathering crust displays opposite features.The transport coefficient of the unconformity surface is controlled by its position in respect to the basal sandstone; it is higher in the ramp region but lower in the adjacent uplifted and sag areas.The content of saturated hydrocarbons increases with the decrease of the content of nonhydrocarbons and asphaltenes.The content of benzo[c] carbazole decreases as the content of benzo[a]carbazole and [alkyl carbazole]/[alkyl ＋ benzo carbazole] increases.This suggests that the unconformity surface is an efficient medium for the transportation of hydrocarbons.The unconformity surface at the bottom of the Paleogene is one of the most important migration pathways in the Sikeshu Sag of the Junggar Basin,which consists of three layers：upper coarse clastic rock,lower weathering crust and leached zone.The upper coarse clastic rock is characterized by higher density and lower SDT and gamma-ray logging parameters,while the lower weathering crust displays opposite features.The transport coefficient of the unconformity surface is controlled by its position in respect to the basal sandstone; it is higher in the ramp region but lower in the adjacent uplifted and sag areas.The content of saturated hydrocarbons increases with the decrease of the content of nonhydrocarbons and asphaltenes.The content of benzo[c] carbazole decreases as the content of benzo[a]carbazole and [alkyl carbazole]/[alkyl ＋ benzo carbazole] increases.This suggests that the unconformity surface is an efficient medium for the transportation of hydrocarbons.

关 键 词：Transportation and accumulation of hydrocarbons LITHOLOGY Rock density SDT and gamma-ray logging Benzo carbazole Alkyl carbazole 

分 类 号：P618.13[天文地球—矿床学]