姬塬油田长2储层成岩作用研究及其对物性的影响

Diagenesis of Chang-2 reservoir and its influence on physical properties in Jiyuan oilfield

通过扫描电镜、铸体薄片、高压压汞、X-衍射及薄片鉴定等方法定性分析了姬塬地区成岩作用对长2储层物性的影响,用定量计算的方法表征各类成岩作用之后孔隙的演化情况。研究结果表明:长2储层砂岩原始孔隙度为37.65%,其中未固结砂岩49.17%的原生粒间孔被压实损失,25.83%的粒间孔被胶结充填,研究区长石溶蚀较发育,产生大量次生孔隙,增加了4%的孔隙。定量计算结果与定性认识较一致。

By using scanning electron microscopy(SEM),casting thin sections identification,mercury injection and X-ray diffraction and based on qualitative identification,the diagenesis and its influence on physical properties in the study area were studied,and then the quantitative calculation was used to show the characterization of pore evolution after all kinds of diagenesis.Research results indicate the original porosity through calculation restoration is 37.65%,among which the impact of compaction is greatest and its loss-rate of porosity is 49.17%,and the loss-rate of porosity of cementation is 25.83%.In the study area,the feldspar dissolution was well developed,a large number of secondary porosity was produced and the dissolution of the reservoir sandstone improved porosity about 4%.The quantitative results and the laboratory test results are basically consistent.