Principles of Trap Development and Characteristics of Hydrocarbon Accumulation in a Simple Slope Area of a Lacustrine Basin Margin:An Example from the Northern Section of the Western Slope of the Songliao Basin,China  

作　　者：Hongyu Wang Tailiang Fan Xuesong Fan 

机构地区：[1]School of Energy Resources,China University of Geosciences [2]Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Accumulation Mechanism,Ministry of Education,China University of Geosciences

出　　处：《Journal of Earth Science》2016年第6期1027-1037,共11页地球科学学刊（英文版）

基　　金：sponsored by the University Science Fund of China (No.292013124)

摘　　要：The western slope of the Songliao Basin is a gently dipping monoclinal slope featured by stratum overlap, gradual change of stratum inclination and limited fault development, which formed during basin depression interrupted by a tectonic inversion stage. Structure, sedimentation and reser- voir characteristics show that the development of the slope and its sand bodies＇ depositional genesis de- termined the types, distribution and evolution of traps. Up-dip wedge-out traps in distributary channels, lenticular traps in distal sand bars and sand sheets in the delta front are the main lithologic trap types and usually have thin reservoir beds, small areas, and are distributed in clusters and belts. The episode of tectonic inversion led to the formation of structural traps and combination traps. The combination traps are characterized by large numbers of thin oil-bearing beds occurring along fold belts. Matching axial directions of distributary channel sand bodies in delta fronts with channel morphology during the period between deposition of sand bodies and sealing by an unconformity above is the key to the search for large scale traps in a simple slope area.The western slope of the Songliao Basin is a gently dipping monoclinal slope featured by stratum overlap, gradual change of stratum inclination and limited fault development, which formed during basin depression interrupted by a tectonic inversion stage. Structure, sedimentation and reser- voir characteristics show that the development of the slope and its sand bodies＇ depositional genesis de- termined the types, distribution and evolution of traps. Up-dip wedge-out traps in distributary channels, lenticular traps in distal sand bars and sand sheets in the delta front are the main lithologic trap types and usually have thin reservoir beds, small areas, and are distributed in clusters and belts. The episode of tectonic inversion led to the formation of structural traps and combination traps. The combination traps are characterized by large numbers of thin oil-bearing beds occurring along fold belts. Matching axial directions of distributary channel sand bodies in delta fronts with channel morphology during the period between deposition of sand bodies and sealing by an unconformity above is the key to the search for large scale traps in a simple slope area.

关 键 词：Songliao Basin simple slope sand body deposition lenticular trap combination trap. 

分 类 号：P618.13[天文地球—矿床学]