鄂尔多斯盆地延长组不同类型砂岩储层物性及其孔隙成因——以天环凹陷盐池地区长9油层组为例  

Physical properties and pore genesis of different sandstone reservoirs in Yanchang Formation,Ordos Basin:A case study of Chang9 reservoir in Yanchi Area of Tianhuan Depression

作　　者：张晓明 赵军辉 郭龙飞 李航 陈嘉荔 狄晓磊 唐曼 曲梦绯 ZHANG Xiaoming;ZHAO Junhui;GUO Longfei;LI Hang;CHEN Jiali;DI Xiaolei;TANG Man;QU Mengfei(No.8 Oil Production Plant,PetroChina Changqing Oilfield Company,Xi’an 710000,China)

机构地区：[1]长庆油田分公司第八采油厂,西安710000

出　　处：《非常规油气》2023年第5期48-55,64,共9页Unconventional Oil & Gas

基　　金：国家重大油气科技专项“超低渗油藏改善开发效果关键技术”(2017ZX05013004)。

摘　　要：在鄂尔多斯盆地延长组致密背景下,深入探究不同类型砂岩物性特征及其孔隙成因对于油气高效勘探开发具有重要意义。利用铸体薄片和扫描电镜等资料对不同砂岩储层进行系统分类,结果表明:研究区发育中-粗粒岩屑长石砂岩、细-中粒岩屑长石砂岩、细-中粒长石岩屑、不等粒岩屑长石砂岩和不等粒长石岩屑砂岩5种类型砂岩。其中前3种类型砂岩占90%以上。中-粗粒岩屑长砂岩、细-中粒岩屑长石砂岩石英和长石刚性碎屑含量高,结构成熟度高,储层物性最好,以中孔低渗、低孔低渗、低孔特低渗和特低孔超低渗为主,含一定中孔中渗储层,其他3类砂岩岩屑和填隙物塑性组分含量高,为低孔特低渗、特低孔超低渗和特低孔特低渗储层。研究区储层孔隙以原生粒间孔为主,其次为长石溶孔、少量岩屑和浊沸石溶孔,绿泥石胶结作用对成岩过程中原生孔隙的保存起到重要保护作用,长石、浊沸石溶蚀对物性起到一定改善作用。刚性矿物含量高、填隙物含量低、碎屑颗粒大以及磨圆度高是孔隙发育的主因,反之孔隙变差。In order to investigated physical characteristics of different sandstone reservoirs,and further to explore forming reason on their pore characteristics by a classified and systematic analysis of the casting thin sections,scanning electron,physical property data,etc.It showed that there develop five types of sandstone reservoir,and coarse-grained and fine-grained lithic arkose,fine-grained feldspathic litharenite are the mainly types,together accounting for over 90%.Both of coarse-grained and fine-grained lithic arkose display higher content of quartz and feldspar,and structural maturity relatively.The types of sandstone reservoir mainly include medium porosity and low permeability,low porosity and low permeability,low porosity and super-low permeability,super-low porosity and ultra-low permeability,also contain a certain amounts of medium porosity and permeability reservoir.The rest three types of sandstone reservoirs showed higher debris and interstitial material,and the sandstone reservoir types include low porosity and super-low permeability,super-low porosity and ultra-low permeability,a small amount of super-low porosity and permeability reservoir.The genetic type of sandstone reservoirs mainly is primary intergranular pore,secondary is feldspar dissolved pore,and a small amount of debris and laumontite dissolved pore.The reservoir of Chang9 is abundant and diverse,and the pore body is primary porosity,the cementation of chlorite has important effect on protecting primary pore,the partial dissolution of feldspar and laumontite are beneficial to improvement of reservoir physical conditions finitely.Higher rigid mineral particle,lower interstitial material,large particle size and higher psephicity etc are the primary reasons for pore abundance,conversely,the pore condition go obviously worse.

关 键 词：天环凹陷 长9油层组 砂岩储层 储层物性特征 孔隙成因 

分 类 号：TE122.2[石油与天然气工程—油气勘探]