渤海湾盆地构造对含油气系统的控制

渤海湾盆地中每个坳陷构成一个大的成熟烃源岩分布区,加上某些凸起的分割,全盆地可划分出13个含油气系统。地堑和半地堑是新生代的基本构造样式,半地堑内含油气系统沿斜坡向外扩展,地堑中的含油气系统基本上限制在两边界断层之间或稍有扩展。盆地早第三纪经历了3个裂陷期,均发育有烃源岩、储层和局部盖层,形成的含油气系统存在着依次改造相互叠加组合的关系。晚第三纪—第四纪属于后裂陷阶段,发育储层和盖层,对早第三纪形成的含油气系统起着增强和改造的作用。构造迁移规律是由南向北、由西向东,由盆地外围向中央。随之主力烃源岩分布、油气生成与运移和油气藏赋存层位也发生有规律变化。使含油气系统在平面上产生差异。

The Control of Tectonism on the Petroleum Systems in the Bohai Bay Basin

Thirteen petroleum systems are recognized in the Bohai Bay basin, considering that each de- pression in it constitutes a big mature hydrocarbon source rock province and that some of them are segmented by rises. Grabens and half-grabens are basic structural styles in the Cenozoic. Petroleum systems in half-grabens extend along the slope, while petroleum systems in grabens are basically restricted between two boundary faults or extend slightly. In the Paleogene the Bo-hai Bay basin experienced 3 syn-rift stages, in which there occurred source rocks, reservoirs and local cap rocks. Petroleum systems formed in the 3 syn-rift stages are characterized by successive reworking and mutual superimposition and association. In the Neogene-Quaternary the post-rift reservoir and cap rocks were developed, thus strengthening and reworking the petroleum systems formed in the Eogene. The tectonic migration from south to north, from west to east and from outside to the center caused regular changes in distribution of major source rocks, petroleum formation and migration and horizons of petroleum occurrence, which further led to lateral differences of petroleum systems.