松辽盆地敖古拉断裂带的封闭性及其对西斜坡油气运聚的控制作用研究

Sealing of Aogula Faulted Zone and Its Control on Oil and Gas Migration and Accumulation of the West Slope of Songliao Basin

敖古拉断裂带位于松辽盆地北部,由北部小林克断裂、中部敖古拉断裂和南部他拉海断裂构成。选取过断裂带的5条地震剖面,利用对接概率方法研究了敖古拉断裂侧向封闭性和断面压力法研究了敖古拉断裂垂向封闭性,结果表明,敖古拉断裂带在主要目的层青山口组、姚家组、嫩江组一段和二段的侧向封闭性良好,垂向封闭性中等到较好;敖古拉断裂带对齐家—古龙凹陷西运的油气起遮挡、转向和汇聚作用,使断裂带以西的油气呈线状分布。

Aogula fault zone locates in the north of the Songliao basin. It includes Xiaolinke fault, Aogula fault and Talahai fault from north to south. Through the analysis of five seismic section data, this paper studies the fault lateral sealing using the docking probability method and the fault vertical sealing using the sectional pressure method. The development characteristics cff the fault zone and the fault sealing indicate that its main formations of K2qn, K2y, K2n^1and K2n^2 have good lateral sealing and its vertical sealing is average to good. Oil-source correlation shows that the oil and gas comes from the Qijia-Gulong sag. The Aogula fault zone may hinder the oil and gas migration, and it can also divide and accumulate the oil and gas migrating to the west slope. This makes oil and gas distribute in strings to the west of the Aogula fault zone.