坪北油田延长组储层岩石物理相分类研究  

Petrophysical Facies Classification of the Reservoir in Yanchang Formation of Pingbei Oilfield

作　　者：王建[1] 梁文川 龚鑑铭[1] 张国威[2] Wang Jian;Liang Wenchuan;Gong Jianming;Zhang Guowei(Research Institute of Exploration and Development, Jianghan Oilfield Branch of SINOPEC, Wuhan 430223, China;College of Petroleum Engineering,Yangtze University, Wuhan 430100, China)

机构地区：[1]中国石化江汉油田分公司勘探开发研究院,武汉430223 [2]长江大学石油工程学院,武汉430100

出　　处：《地质科技情报》2018年第1期53-60,共8页Geological Science and Technology Information

基　　金：中国石化股份有限公司重点攻关项目"坪北特低渗透油藏深度水驱技术与应用"(P15141)

摘　　要：鄂尔多斯盆地坪北油田延长组广泛发育一套低孔特低渗透储层。各小层渗透率差异性较小,均在1×10-3μm2左右,开发上却表现出了强烈的平面、纵向非均质性特征。目前行业内并没有形成成熟的方法对该类储层进一步细分来体现这种特征。基于岩心、薄片、X射线衍射、压汞等各类分析测试资料,针对研究区强非均质性特征,从储层岩石物理相的角度开展了储层分类方法的研究,得到了几项重要成果:(1)经典岩石物理相概念中的裂缝相描述在坪北油田受到资料情况限制较难实现,可以扩展为孔隙结构相的概念加以描述分析;(2)该区域特低渗透储层沉积相可分为水下分流河道、河口坝、分支间湾3种;成岩相可分为碳酸盐胶结相、强压实致密相、弱压实-弱溶蚀相、不稳定组分强溶蚀相4类;孔隙结构相可分为小孔微喉相、中孔细喉相、中孔中喉相3类;(3)结合沉积相、成岩相与孔隙结构相,可将研究区岩石物理相划分为4类,对应储层级别为非-差、较差、中等、好。采用改进的岩石物理相划分方法能够有效地将低孔特低渗透油藏进一步细分,该成果对油田当前的滚动勘探油藏评价及老区细分开发调整具有较大的现实意义,同时对于相似油藏的储层分类研究提供了一种有效方法。A low porosity and low permeability reservoir is widely developed in Yanchang Formation of Pingbei Oilfield in Ordos Basin.Each layer has a small difference of permeability about 1×10-3μm2,but there has a strong heterogeneity in the oilfield development from plane and longitudinal aspects.At present,there is no mature method in the industry to further subdivide the reservoir to reflect the characteristics.Based on the data of cores,thin sections,X-ray diffraction and mercury intrusion,as well as the strong heterogeneity characteristics of this area,this paper studies the reservoir classification method from the point of view of reservoir petrophysical facies,and has reached several important achievements：（1）The concept of fractures in the concept of classical petrophysical facies is described in the Pingbei Oilfield,which is difficult to be realized by the data case.It can be extended to describe the concept of pore structure.（2）This ultra-low permeability reservoir can be divided into three kinds：underwater diversion channel,estuary dam,and river bay;diagenetic facies can be divided into four kinds：carbonate cement,strong compaction dense,weak compaction-weak dissolution,unstable components strong dissolution.Pore structure facies can be divided into small hole micro-throat,medium-hole throat,medium hole in the throat three categories.（3）Combining the sedimentary facies,diagenetic facies and pore structure facies,the petrophysical facies of the research area can be divided into four categories,correspondingly to the reservoir level is not bad,poor,medium and good.The improved method of petrophysical facies can effectively subdivide the low-porosity and ultra-low permeability reservoirs.The research results prove to be of great practical significance in the evaluation of the current rolling exploration reservoir and the subdivision adjustment of the old oil field.Simultaneously,this study provides an effective method for reservoir classification in similar reservoirs.

关 键 词：鄂尔多斯盆地 延长组 岩石物理相 孔隙结构相 

分 类 号：P618.130[天文地球—矿床学]