塔中北斜坡地区奥陶系鹰山组储层差异性分析

Reservoir differences of the Ordovician Yingshan Formation in the northern slope of Tazhong

奥陶系鹰山组海相碳酸盐岩为塔中北斜坡地区的主体产层和储集层,区内多个井区的沉积环境和储层岩性十分相似,但储层物性差别很大。利用层间岩溶、埋藏岩溶、构造作用以及流体性质等方面的差异,详细分析了鹰山组储层差异性。结果表明:层间岩溶期孔洞层发育的区块差异性是导致储层差异性的根本原因;断裂裂缝发育的区块差异性造成了流体运移通道的差异性;埋藏期3期流体运移方向的差异性最终导致了储层发育及油气聚集的差异性。

The marine carbonate rocks of the Ordovician Yingshan Formation are regarded as the main producing formation and reservoir in the northern slope of Tazhong.The depositional environment and lithology in different well areas are very similar,while the reservoir properties show a great difference.This paper applied the information of interstratal karst,buried karst,tectonic action and fluid property to analyze the reservoir differences of Yingshan Formation.The result shows that the block differences of cavity development in the interstratal karst period lead to the reservoir differences,fracture development leads to the differences of fluid migration pathways,and the differences of fluid migration direction of the third buried period eventually result in the differences in reservoir development and hydrocarbon accumulation.