迈陈凹陷东部构造特征及其对油气成藏的影响

为了明确迈陈凹陷东部构造特征与油气成藏的关系，利用地震、钻井等资料对新生代断裂几何学特征、活动性进行了分析。结果表明，研究区经历了断陷、断坳过渡、坳陷等演化过程，受到多期次构造运动的影响，分层差异变形，发育了上、下两套断裂体系，分别为早期张性断裂和晚期张扭性断裂，这些断裂既具有新生性，也具有对早期断裂的继承性、改造性。因此构成了丰富多样的组合样式。不同断裂类型及组合对油气成藏的控制作用也存在差异，边界断层控制了该区的基本构造格架及烃源岩的形成分布；断裂组合的多样性使得圈闭类型多样；早期消亡的断裂可起到良好的遮挡作用，继承性活动断裂或向下断至源岩层的晚期断裂可起到油气向浅层圈闭运移的通道作用。

Tectonic characteristics and their impacts on hydrocarbon accumulation in Eastern Maichen Sag

In order to clearly make out the relation between tectonic characteristics of eastern Maichen Sag and hydro- carbon accumulation, the data of seism, drilling, etc. were used to analyze Cenozoic fault geometry feature and activity. And the result indicates that the Maichen sag has experienced evolution processes of rifting stage, rifting and sagging stage and sagging stage. By the influences of multistage tectonic movements, the sag had characteristics of differential delaminating deformation and developed two sets of fault systems which are early extension faults and late tensional shear faults, respec- tively. These faults have both new ones and,inherited and reconstruction ones from early stage fractures. As a result, these faults contributed to a variety of combination styles. Different fault types and combinations have different controls on hydrocarbon accumulation. Boundary faults controlled basic tectonic framework and source rocks distribution. The diversity of fault combination resulted in various entrapment types. The early disappearing faults have good blocking effect, and inheritance active faults or other later faults, which broken down to source rock, can be the hydrocarbon migration channel to the shallow traps.