中国东北区晚中生代盆地构造与含油气系统

TECTONICS AND PETROLIFEROUS SYSTEMS OF LATE MESOZOICBASINS IN NE CHINA

中国东北区晚中生代含油气盆地形成有两期，各具不同的构造环境。第一期盆地（Ｊ_（１＋２））为断陷盆地；第二期盆地（Ｊ_３－Ｋ）为ＮＥ向分布的裂陷盆地群。晚白垩世在松辽盆地发育大型湖泊，形成规模巨大的陆相油气聚集。郊－庐断裂左行走滑作用及周边构造应力场变化导致盆地内平移断层和一系列的反转构造，为油气聚集提供了优越的圈闭条件。根据盆地构造发育史、充填特征及热演化史，将东北区中生代含油气系统划分为单源型和多源叠合型两大类，各自有自身的分布特征。

The formation process of late Mesozoic petroliferous basins in the NE China can be divided into two development stages which were formed in different tectonic environments. The first－stage basins (J_(1+2))belonged to faulted basins,and the second－stage basins (J_3－K)were rift basin group with NE strike. During Late Cretaceous, Songliao basin became a large－scale lake basin,which became a large continental petroleum－rich basin. The sinistral strike－slip movement of the Tan－Lu fault and the changes of tectonic stress field resulted in many parallel faults and a series of inversion structures within Songliao basin. These structures provided excellent traps for oil and gas accumulations. Based on the tectonic development history of the basins, filling characteristics and thermal evolution history, the petroliferous systems of late Mesozoic basins in the NE China can be classified into single－source systems and superimposed systems with multiple sources,each of them has its own distribution characteristics.