ACCUMULATION CONDITIONS AND PERSPECTIVES OF COAL-DERIVED HYDROCARBON OF CARBONIFEROUS-PERMIAN IN NORTHERN JIZHONG DEPRESSION, BOHAI BAY BASIN

Suqiao—Wenan is the first area in the Bohai Bay Basin where coal-derived hydrocarbon of the Carboniferous—Permian is found.New discoveries have been made till now.In order to clarify accumulation rules of hydrocarbon from the Carboniferous—Permian in the research area,analyses of accumulation background such as secondary hydrocarbon generation of coal source rocks have been made.3 accumulation models have been concluded: 1)self-generation and self-accumulation model of the Carboniferous—Permian;2)P_z2 generation and P_z1 accumulation model in buried hills;3)P_z2 generation and Paleogene accumulation model.Oil generation window in 3 500—5 000 m interval of the Carboniferous—Permian is the key factor for the 1st model.The Ordovician buried hills contacting with the Carboniferous—Permian source kitchen by faults over 300 m wide are the key factors for the 2nd model.Active faults communicating reservoirs with source kitchen control the 3rd model.3 favorable zones are pointed out for further exploration.