摘要:
英买潜山区白云岩油气藏受白云岩物性夹层控制,在开发后期局部富集的剩余油,是开发挖潜稳产的重要目标。文章通过对白云岩岩心、薄片、物性和测井资料的分析,描述和识别了英买潜山区寒武系-下奥陶统蓬莱坝组白云岩特征,认为本区主要发育泥晶白云岩夹层、泥粉晶白云岩夹层、粉晶白云岩夹层三套。垂向上,白云岩夹层主要发育在各米级旋回向上变浅序列的下部,成透镜状、条带状分布,厚度为0.5~2.5 m 不等。该区夹层起着渗流屏障作用,控制着剩余油分布,影响生产井的无水采油期时间和含水率上升速度。
Abstract:
The crack-cave type dominates dolomite reservoirs in the Yingmai buried-hill area,which include dissolved holes,karst caves and karst cracks,as well as local big unfilled caves as storage space.The bottom water massive reservoirs in dolomite buried hills are controlled by dolomite intercalation with special physical properties.Local residual oil enrichment areas are the main object in the late exploitation.Basing on analyses of cores,thin sections,physical properties and well logging data,this work made a description and identifi-cation of dolomite from Cambrian to lower Ordovician in the Penglaiba formation of the Yingmai buried-hill area.The results show that,the intercalation in this area can be classified into 3 categories,micritic dolomite intercalation,mud dolomite intercalation and powder dolomite intercalation.Vertically,dolomite intercala-tion mainly developed in the lower part of the shallow upward sequence in each meter scale cycles,and al-ways spread as lens or bands of which the thickness is between 0.5 and 2.5 meters.In this area,the interca-lation played the screen role to seepage and controlled the distribution of residual oil,and also affected the water breakthrough time and the rising rate in production.
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