阿尔金山山前带东段构造特征与油气成藏的关系

The relationship between structural features and hydrocarbon entrapment in the east part of Altyn Tagh piedmont

通过对区域地质资料结合地球物理资料的综合研究表明,柴达木盆地阿尔金山山前带东段发育两组成因不同的断裂体系,分别受控于阿尔金走滑作用和东昆仑冲断作用。坪东、鄂东、牛北等主要断裂控制了"隆坡相间"的构造格局,各构造单元的形成演化差异性明显,导致了油气成藏特征的不同。早期活动的NNW向深大气源断裂控制油气富集带的形成,不同类型构造单元控制了油气藏的主要类型,晚燕山构造运动控制了油气长期运移的优势指向区和富集层系。

Based on both geological and geophysical data,our research finds out that two fault systems with different structural origins were developed in the east part of Altyn Tagh piedmont.One of the fault systems is controlled by the Altyn Tagh strike-slip effect,and the other is controlled by the east Kunlun thrusting effect. The structural framework influenced by the faults in Pingdong,Edong,and Niubei is the uplift slope phase in the region.The difference of the evolution of each tectonic unit is obvious and the feature of hydrocarbon entrapment is different.The NNW discordogenic faults are gas source faults,which are active at the early stage.Their tectonic activity controls the formation of hydrocarbon accumulation belt.The type of oil and gas reservoir is decided by the type of the tectonic unit.Late Yanshanian movement controls the direction of oil and gas migration in a long period,which indicates the enrichment layer series.