鄂尔多斯盆地中部姚店油田上三叠统长4+5储层砂岩的成岩作用  

Sandstone diagenesis of Chang 4+5 reservoir group of the Upper Triassic Yanchang Formation in Yaodian oilfield,central Ordos basin,China

作　　者：雷晓岚[1,2] 张林 于波 李江 吴剑 

机构地区：[1]中国科学院地质与地球物理研究所,北京100029 [2]陕西延长石油(集团)有限责任公司,陕西延安717208 [3]中国石油川庆钻探工程有限公司工程技术研究院,陕西西安710021 [4]陕西延长石油(集团)有限责任公司研究院,陕西西安710069

出　　处：《地质通报》2009年第5期603-608,共6页Geological Bulletin of China

基　　金：国家自然科学基金项目(编号:90210022)资助

摘　　要：根据砂岩薄片、铸体薄片、扫描电镜、X-衍射等分析,对姚店油田三叠系延长组长4+5油层砂体的岩石学特征、成岩作用阶段划分、成岩作用类型及其对孔隙的影响进行了研究。研究结果表明,该区长4+5储层储集砂体成分主要以长石砂岩为主。成岩作用类型包括压实作用、胶结作用和溶蚀作用。砂岩经历了早期成岩阶段A、B期和晚期成岩阶段A期(A1、A2期)的成岩演化过程。早期的压实作用、多种矿物胶结作用是使物性变差的2个重要因素,但早成岩阶段形成的绿泥石膜保护了一些砂岩的原生孔隙;晚成岩阶段A期的溶蚀作用,特别是长石的溶蚀是储层物性变好的重要成岩控制因素。Based on the analysis of casting lameUa, scan electron microscope and X-ray diffractions of sandstone lamella ,this paper has conducted research on the petrology characteristic, diagenesis stage division and its influence on porosity of Chang-4＋5 Reservoir in Yaodian oilfield of central Ordos Basin. It is indicated that the main reservoir sand in the area is arkose with diagenesis type including compaction, cementation and dissolution. Overall diagenesis process includes early stage （A and B phases） and late stage （A1 and A2 phases）. The early compaction and multi-mineral cementation are the major factors that leads to poor petrophysical property of Chang-4＋5 Reservoir, but the ehlorite film formed during the early stage helps to preserve some primary poriosity; dissolution at the phase A during the late stage, especially feldspar dissolution is one of significant factor controlling the quality of reservoir.

关 键 词：鄂尔多斯盆地 成岩作用 上三叠统延长组 长4+5储层 

分 类 号：P534.51[天文地球—古生物学与地层学] P588.2[天文地球—地质学]