巨厚层均质砂岩储集层渗流屏障特征及分布规律

针对塔里木盆地塔中4油田CⅢ油藏储集层,以岩心、测井等资料为基础,对研究区泥质、钙质和钙泥质3类渗流屏障特征进行了表征,通过对不同类型渗流屏障的岩心观察、岩性物性分析、测井响应特征分析和形成机理研究,建立了储集层内部不同类型渗流屏障的划分标准。以平行渗流屏障模式为地质模式基础,结合生产动态资料,根据不同渗流屏障对储集层流体渗流的影响,将研究区井间渗流屏障分为完全遮挡型、部分遮挡型和完全不遮挡型3种,并明确了渗流屏障在垂向上和平面上的分布规律。垂向上,不同层段的渗流屏障对流体渗流影响不同,上交互亚段和下交互亚段上部渗流屏障对流体渗流影响最大,而平面上研究区西北部渗流屏障最为发育。充分认识储集层渗流屏障特征、分布规律及其对流体渗流的影响,对油田剩余油的挖潜和采收率的提高具有重要的地质意义。

Characteristics and Distribution of Seepage Barrier in Massive Homogeneous Sandstone Reservoirs

Regarding the CⅢreservoir in Tazhong?4 oilfield of Tarim basin and on the basis of core and logging data,3 types of argilla?ceous,calcareous and argillaceous?calcareous seepage barriers are characterized.Based on the core observation,lithological and physical property analysis,logging response analysis and forming mechanism study of the seepage barriers,a classification standard is established for the different seepage barriers within reservoirs.Taking the parallel seepage barrier model as the basis of geological model and combin?ing with the production performance,fully occluded,partially occluded and non occluded interwell seepage barriers are classified accord?ing to the influences of the barriers on reservoir fluid flowing in the study area,and the vertical and horizontal distribution laws of the barri?ers are verified.Vertically the seepage barriers of different intervals have different impacts on fluid flowing,and horizontally the seepage barriers are very developed in the northwest of the study area.Fully understanding the reservoir seepage barrier characteristics,distribution and impact on fluid flowing will provide an important geological basis for remaining oil potential tapping and oil recovery improvement.