摘要
以济阳坳陷东营凹陷古近系页岩储层为研究对象,利用岩石薄片观察、X射线衍射全岩矿物含量分析、电子探针分析、碳氧同位素测试分析、氩离子抛光和场发射环境扫描电镜分析、低温氮气吸附实验等技术方法,研究孔隙类型及组合样式,分析成岩流体环境及架构矿物演化特征,划分成岩阶段,明确孔隙的发育演化主要受控于黏土矿物转化和碳酸盐矿物的含量、成岩作用强度及其溶蚀程度,增孔和减孔机制的界限并不严格.研究结果表明:东营凹陷页岩储层发育基质孔隙组合、基质孔隙-有机孔隙组合、裂缝沟通基质孔隙组合等多种类型孔隙组合(包含微裂缝),孔隙面貌复杂;受地层水介质及原始沉积环境影响,局部层段酸性碱性流体交替控制细粒物质的成岩演化,总体呈现由碱性—弱碱性—酸性—弱碱性的成岩环境变化特征;有机质成熟度较低(Ro<1.0%),成岩阶段处于中成岩阶段,早成岩B期—中成岩B期是孔隙演化的关键时期;压实作用下黏土矿物的脱水转化与催化生烃、溶蚀与沉淀作用共存、方解石近源重结晶与有机质生烃排酸的共同作用造成了孔隙的动态演化;黏土矿物转化、有机质生烃、方解石等脆性矿物的成岩作用对储层孔隙体系的演化起到了重要的作用.
A study was conducted on the mud-shale in Paleogene Shahejie formation,Dongying sag,Jiyang depression to investigate the pore types and their combinations,using the rock thin section observation,X-ray diffraction analysis,electron probe micro element scanning,carbonoxygen isotopic test,argon ion polishing and scanning electron microscopy（SEM）analysis and nitrogen adsorption-desorption method.The diagenetic fluid environment and architecture mineral evolution characteristics were analyzed,and the diagenesis stage was divided.the development and evolution of pores are mainly controlled by the conversion of clay minerals,the content of carbonate minerals,the strength of diagenesis and the degree of dissolution.The in-crease and reduction mechanism of boundary is not strict.Results show that there are three major pore assembly types in shale reservoirs of Dongying sag：matrix pores,matrix-organic pores and microfissure matrix pores.The pore structures are complex.Affected by formation water medium and depositional environment,local layer acidic and alkaline fluids alternately control the diagenetic evolution of fine grained material.The general variation trend of diagenetic environment is alkaline,weak alkaline,acid,weak alkaline.The maturity of organic matter is low（Ro〈1.0%）.The diagenetic is in the middle diagenesis phase,and the early diagenetic B stage to middle diagenetic B stage is the crucial time period for porosity evolution.Under the compaction effect,the mutual impact of clay minerals dehydration and catalysis of organic hydrocarbon generation,the dissolution and deposition coexistence,the calcite nearsource recrystallization,the hydrocarbon generation and acid discharge of organic matter lead to the pores dynamic evolution.Clay minerals transformation,organic matter hydrocarbon generation and the calcite and other brittleness minerals diagenesis play an important role in the evolution of reservoir pore system.
作者
张顺
ZHANG Shun(Reserch Institute of Petroleum Exploration and Development,Shengli Oilfield, SINOPEC, Doingying, Shandong 257022,China;Working Stations for Postdoctors of Shengli Oilfield,Doingying, Shandong 257000,China)
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2018年第3期562-578,共17页
Journal of China University of Mining & Technology
基金
中石化胜利油田博士后课题基金(K26)
国家重点基础研究发展计划(973)项目(2014CB239102)
国家自然科学基金项目(41372107)
关键词
页岩储层
孔隙组合
成岩演化
增孔和减孔机制
东营凹陷
古近系
shale oil reservoir
pore assembly types
diagenesis evolution
mechanism of pore increase and reduction
Paleogene
Dongying sag
