济阳坳陷沾化凹陷罗家地区古近系沙河街组页岩储集特征分析*

利用岩石薄片和扫描电镜分析等测试技术, 可以将济阳坳陷罗家地区古近系沙河街组页岩段储集空间分为孔隙和裂缝两大类。孔隙又可以分为黏土矿物晶间孔、碳酸盐矿物晶间孔、黄铁矿晶间微孔、碎屑颗粒溶孔和砂质粒间微孔5个亚类；裂缝分为成岩裂缝和构造裂缝两大类, 成岩裂缝又可以分为层间裂缝和粒缘裂缝两类。裂缝与基质孔隙之间, 存在一个微米尺度的重合带, 反映了储集空间发育继承性的特点, 油气聚集在以层间裂缝为中心, 粒缘裂缝等次级裂缝和较大的碳酸盐晶间孔为骨架, 以各类晶间孔隙、黏土微孔和溶蚀孔隙为基质的储集空间网络中。储集空间发育与岩性关系密切, 纹层状泥质灰岩物性较好, 相应的页岩物性具有基质渗透率极低和裂缝导流能力较强的特点。

Shale reservoir characteristics analysis of the Paleogene Shahejie Formation in Luojia area of Zhanhua sag,Jiyang Depression

Using rock thin section and scanning electron microscopy analysis of micro-testing techniques, Jiyang Depression Luojia area shale reservoir space can be divided into two major categories of pores and fractures. Pores can be divided into intercrystalline pores of clay minerals, carbonates minerals intercrystalline pores, pyrite intercrystalline pores, dissolved pores in clastic grains and micro-dissolved pores of grains five sub-categories. The fractures can be divided into diagenetic fractures and structure fractures, and the former can be subdivided into interlaminar fractures and grain boundary fracture. Fractures and matrix porosity exist between a micron scale coincides with, reflecting the development of reservoir space inherited characteristics. Oil and gas accumulate in a framework, where inter-layer cracks as the center, grain boundary cracks and other cracks and larger secondary carbonates intercrystalline pores for the skeleton, various types of intercrystalline porosity, clay pores and dissolved pores as the matrix. Lithologic reservoir space development are closely related with laminated argillaceous limestone and argillaceous limestone has better properties, physical properties, the corresponding shale has very low matrix permeability and good fracture conductivity.