鄂尔多斯盆地西缘断裂特征与油气运聚研究

The fault feature and hydrocarbon accumulation in the western Ordos Basin

长庆油田勘探开发研究院,陕西西安 710021

Changqing Oil Field Branch Company of China Petroleum, Xi'an 710021, China

针对鄂尔多斯盆地西缘断裂复杂的特征,采用地震剖面解释方法,总结归纳出3种主要的构造样式.即逆冲推覆、扭动构造及反转构造。不同构造样式在平面上的分布各异,其中,逆冲推覆构造的下盘是油气聚集的有利场所。断裂对沉积体系控制作用的分析表明,在海相和湖相沉积体系中,单一断裂以及断裂组合的坡折带位置都是油气富集的主要区域;断裂的多期活动性,不仅改善了断裂附近储层的储集性能,而且造成了储盖组合的横向差异和纵向叠加,油气运聚受断裂活动差异的控制。

It is very close between fault structure and oil-gas accumulation, according to complicated characteristic of faults in the western Erdos Basin, adopt the seismic interpretation, structural styles are divided into three types, namely overthrust nappe, shear structural system and retrograde structural. Different structural styles are distributed into different areas on the plane. In these different structuralpatterns, the hang walls of overthrust nappe are the main location of oil-gas accumulation. With the analysis of faults and sedimentary systems, the slope break zones of lonely fault or fault combination are mainly locations of oil-gas accumulation in the sedimentary system of marine and lacustrine facies. The fault movement, not only the reservoir bed are improved, but also the assemblage of reservoir bed and capping bed are repeated on the portrait, altered on the landscape orientation. In a word, the movement and accumulation of oil and gas are influenced by the different of fault characteristic.