鄂尔多斯盆地清涧地区山2 3致密砂岩储层成岩作用与有利成岩相带  

Diagenesis and favorable diagenetic facies tract of tight sandstone of Shan23 reservoirs in Qingjian region of Ordos Basin

作　　者：杨国平[1] 樊志强[1] 贾连超[1] 丁熙[1] 李元觉[2] 段雨辰 马俊明[1] 

机构地区：[1]中国石油长庆油田分公司第二采气厂 [2]西安石油大学理学院

出　　处：《低渗透油气田》2014年第2期30-36,共7页

摘　　要：鄂尔多斯盆地清涧地区山23段砂岩为一套典型的低孔、低渗储层，平均孔隙度为4．56％，平均渗透率为0.67mD，主要孔隙类型有剩余粒问孔、溶蚀孔和晶间孔。孔隙结构以中粗孔径一细喉道为主。山2、致密砂岩储层经历了复杂的成岩作用，如压实压溶、胶结、溶蚀等作用，其中压实和胶结等破坏性成岩作用使储层的原生孔隙大大减少．使储层的孔隙度和渗透率降低，导致储层变得致密，而溶蚀作用可在一定程度上改善储层的物性。综合多项成岩阶段划分指标，清涧地区山23段砂岩已进入晚成岩B期，部分指标进入C期。根据成岩作用特点，将研究区山2，段划分出5种成岩相，清涧地区主要发育弱压实、石英加大较强、溶蚀相和强压实、高岭石胶结相两大成岩相，其中弱压实、石英加大较强、溶蚀相是最有利成岩相带。The sandstone of Shan23 Member in Qing, iian area of Ordos Basin is typieally a set of low porosity and low permeability reservoirs, with the average pornsity of 4.56% and the average permeability of 0.67 roD. The main pore types are residual intergranutar pores, corrusiun pores and intercrystalline pores. The pore structure is mainly the coarse pores - thin throats. The Shan23 tight sandstone reservoir has experieneed a complex diagenesis, such as pressure solution eompaction, cementation, dissolution and other effect. The compaction, cementation and other destructive diagenesis make primary pores reduced greatly. The reservoir porosity and permeability decreased. This caused the reservoir tight, while the corrosion action can improve the properties of the reservoir to some extent. With muhiple integrated diagenetic classification indexes, the sandstone in Qingjian Shan23 Member has entered the later diagenctic B stage and parts of indexes into the C period. According to the diagenesis characteristics, the Shan23 are divided into 5 diagenetic facies for the study areas. There were mainly two diagenetic facies nf the weak compaction, strong quartz growth, corrosion faeies, and the strong compaction, kaolinite cementation facies developed in Qingjian region, of which the weak compaction, strung quartz growth, corrosion facies are the most favorable diagenetic facies tracts.

关 键 词：鄂尔多斯盆地 清涧地区 致密砂岩 储层特征 孔隙结构 成岩作用 成岩相 

分 类 号：TE373[石油与天然气工程—油气田开发工程]