演武地区延8段储层微观孔隙结构特征及成因  

Characteristics and genesis of microscopic pore structure of Yan 8 Member reservoir in Yanwu area

作　　者：肖胜东 王震亮[1,2] 潘星 王联国[5] 朱立文 刘一婷 XIAO Shengdong;WANG Zhenliang;PAN Xing;WANG Lianguo;ZHU Liwen;LIU Yiting(State Key Laboratory of Continental Dynamics(Northwest University),Xi′an 710069,China;Department of Geology,Northwest University,Xi′an 710069,China;Research Institute of Shaanxi Yanchang Petroleum(Group)Co.,Ltd.,Xi′an 710065,China;Exploration and Development Research Institute,Changqing Oilfield Company,PetroChina,Xi′an 710018,China;No.11 Oil Production Plant,Changqing Oilfield Company,PetroChina,Qingyang 745000,China)

机构地区：[1]大陆动力学国家重点实验室(西北大学),陕西西安710069 [2]西北大学地质学系,陕西西安710069 [3]陕西延长石油(集团)有限责任公司研究院,陕西西安710065 [4]中国石油长庆油田分公司勘探开发研究院,陕西西安710018 [5]中国石油长庆油田分公司第十一采油厂,甘肃庆阳745000

出　　处：《断块油气田》2024年第1期86-95,105,共11页Fault-Block Oil & Gas Field

基　　金：中国石油长庆油田分公司科学研究与技术开发项目“殷家城-合道地区侏罗系油藏富集规律及建产目标区优选”(技2021-90-5)。

摘　　要：鄂尔多斯盆地演武地区侏罗系延安组是主要的含油气层,为明确该区储层复杂多样的孔隙结构特征及成因,运用精细岩心描述、铸体薄片鉴定、阴极发光、扫描电镜和高压压汞分析等技术,对侏罗系延8段储层微观孔隙结构特征进行详细表征,并综合分析了宏观沉积作用、微观成岩作用对孔隙结构的双重控制。结果表明:延8段储层岩性主要为长石石英砂岩,孔隙度平均为13.99%,渗透率平均为177.33×10^(-3)μm^(2),孔隙类型主要为残余粒间孔和粒间溶孔,孔隙结构以中孔中细喉道为主,属于低孔中渗透储层。储层物性平面上受沉积相带的控制,垂向上明显受成岩作用的影响。不同成岩相储层孔隙结构差异明显:压实胶结相和含铁碳酸盐胶结相绝大多数孔隙和喉道被假杂基化的塑性颗粒或碳酸盐胶结物充填,孔隙类型主要为残余粒间孔,孔隙结构类型以小孔细喉道为主,物性较差;强溶蚀相和自生石英-长石弱溶解相次生溶孔发育,储层物性得到改善,孔隙连通性好,孔隙结构类型以中孔粗喉道为主,是油气富集的有利相带。The Jurassic Yan′an Formation in the Yanwu area of the Ordos Basin is the main oil and gas bearing layer,and in order to clarify the complex and diverse pore structure characteristics and genesis of reservoirs in this area,the microscopic pore structure characteristics of the Yan 8 Member reservoir in the study area were characterized in detail through tecniques such as fine core descriptions,casting thin section identification,cathodoluminescence,scanning electron microscopy and high pressure mercury injection.At the same time,the dual control of pore structure by macroscopic sedimentary and microscopic diagenesis are comprehensively analyzed.The results show that the lithology of the reservoir in Yan 8 Member is mainly feldspar quartz sandstone,the average porosity of the reservoir is 13.99%,and the average permeability is 177.33×10^(-3)μm^(2).The pore type is dominated by residual intergranular pores and intergranular dissolved pores,and the pore structure is dominated by mesopore-thin throat.The reservoir is a low-porous and moderately permeable reservoir.The physical properties of the reservoir are controlled by the sedimentary facies belt in the plane,and obviously affected by the diagenesis in the vertical direction.The pore structures of reservoirs with different diagenetic facies are obviously different:most of the pores and throats in the compacted cemented facies and the iron-containing carbonate cemented facies are filled with pseudomatrix plastic particles or carbonate cement.The types of pores are mainly residual intergranular pores,and the pore structure is mainly small pores and fine throats,which have poor physical properties.The secondary dissolution pore of strong dissolution facies and the authigenic quartz-feldspar weak dissolution facies are well developed.Therefore,reservoir physical properties have been improved and pore connectivity is good.The pore structure is mainly mesopore-thick throat type,which is a favorable facies belt for oil and gas enrichment.

关 键 词：成岩相 成岩作用 孔隙结构 储层特征 延安组 鄂尔多斯盆地 

分 类 号：TE122.23[石油与天然气工程—油气勘探]