关键词: 基底断裂, 走滑, 断层-岩性油藏, 油气聚集, 长岭凹陷, 松辽盆地

Abstract: There mainly developed three groups of basement faults including the strike orientations of north-east(NE),north-west(NW) and east-west(EW) in the Southern Songliao Basin.The basement faults were controlled by the different tectonic frameworks and stress fields in Mesozoic and have the activities of extension,left-lateral striking slip and compression actions.The regional structure framework and the secondary structure belts of the Southern Songliao Basin were strongly influenced and formed by the basement faults. The relationships between second-order faults developed in overlaying of the Cretaceous strata and basement faults developed in Yingtai-Sifangtuozi area and Changling Sag were analyzed.It is shown that the second-order faults played an important role in the formation of fault-lithological types of hydrocarbon accumulation in the Southern Songliao Basin.The NW striking second-order faults in Changling Sag were resulted from the left lateral action of NE striking basement fault,and the SN striking Tuodong fault in Yingtai-Sifangtuozi area was controlled by NE and NNW striking basement faults.Meanwhile,the NW striking basement faults,acting as tear faults,cut and separate the NE fault belts.The NE striking fault belts and SN striking fault belts near Nenjiang River may be the favorable plays to get new discovery of lithological reservoir in the near future.

Key words: basement fault, striking slip, fault-lithological oil pool, hydrocarbon accumulation, Changling Sag, Songliao Basin