渤海湾盆地冀中坳陷北部石炭—二叠系煤成油气成藏条件及勘探前景

苏桥—文安是渤海湾盆地最早发现石炭—二叠系煤成油气的地方,近期仍有新的发现。为查明研究区源于石炭—二叠系的油气成藏规律,进行了煤系烃源岩二次生烃等成藏背景分析,发现该区存在3种成藏模式:石炭—二叠系自生自储、上古生下古储潜山以及古生新储第三系混源。3 500～5 000 m的石炭—二叠系生油窗是自生自储型油气成藏的控制要素;断距超过300 m,造成奥陶系与石炭—二叠系烃源灶对接,是潜山油气成藏的控制要素;活动性断层沟通煤系源灶,是第三系混源成藏的条件。还指出了3个有利前景区,明确了进一步勘探方向。 

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.