摘要
基于岩心观察、铸体薄片、扫描电镜、压汞曲线、物性分析等资料,对鄂尔多斯盆地王沟门地区延长组长8储层特征、成岩作用特征及孔隙发育的控制因素进行分析。结果表明,长8储层岩石类型主要为长石砂岩及岩屑长石砂岩,岩屑及填隙物成分较高;储层非均质性强、物性差,长8储层孔隙度平均为8.60%,渗透率平均为0.39×10^(-3)μm^(2),均属特低孔、特低渗储层;储层物性受沉积与成岩作用控制,水下分流河道砂体为有利沉积相带;中成岩A期,以机械压实、胶结及少量溶蚀作用为主,长石及塑性岩石的快速压实及碳酸盐、黏土矿物的胶结致使储层孔隙大幅度减少;中成岩B期,溶蚀作用增强,次生孔隙发育,利于孔隙的生成和保存,但压溶及中晚期胶结作用进一步加大了储层致密程度。
Based on core observation,casting thin section,scanning electron microscope,mercury injection curve,and physical property analysis,the characteristics of reservoir and diagenesis,and controlling factors of reservoir pore development of Chang 8 reservoir in Yanchang Formation,Wanggoumen area of Ordos Basin are studied and analyzed.The results show that the feldspathic and lithic feldspathic sandstones are the main types,the composition of lithic and interstitial materials is high,with strong heterogeneity and poor physical properties.The average porosity and permeability are 8.60%and 0.39×10-3μm 2 respectively,belonging to ultra-low type.Controlled by sedimentation and diagenesis,the underwater distributary channel sand body is a favorable sedimentary facies zone.In the middle diagenetic stage A,it is mainly of mechanical compaction,cementation and a small amount of dissolution.The rapid compaction of feldspar and plastic rocks and the cementation of carbonate and clay minerals lead to a sharp reduction in reservoir porosity.In the middle diagenetic stage B,the dissolution is enhanced and secondary pores are developed,which is good for the formation and preservation of pores,while the pressure solution and the middle-to-late cementation further increase the density of the reservoir.
作者
张聪
郭峰
陈一凡
郭睿婷
张颖
ZHANG Cong;GUO Feng;CHEN Yifan;GUO Ruiting;ZHANG Ying(School of Earth Sciences and Engineering,Xi’an Shiyou University,Xi’an,Shaanxi 710065,China;Shaanxi Provincial Key Laboratory of Oil and Gas Accumulation Geology,Xi’an,Shaanxi 710065,China;Qinghai Oilfield Company,PetroChina,Mangya,Qinghai 816400,China)
出处
《石油地质与工程》
CAS
2023年第3期31-37,共7页
Petroleum Geology and Engineering
