库木库里盆地第三系储层成岩作用及孔隙演化研究

Diagensis And Porosity Evolution of Tertiary Reservoirs in Kumukuli Basin

库木库里盆地是一个以第三系为主体的沉积盆地,该盆地储层岩性主要为岩屑长石砂岩、长石岩屑砂岩,为低孔低渗储集岩。通过岩心观察,结合薄片鉴定、扫描电镜、阴极发光和物性等资料分析后认为,储层经历了压实作用、胶结作用、交代作用、溶解作用等成岩作用,目前已达到了晚成岩阶段。储集砂岩经成岩演化其原生孔隙大部分被破坏,主要以次生孔隙为主,可见成岩作用是控制该区储层物性特征的一个关键因素。在孔隙演化过程中,压实、胶结作用起主要破坏性作用,溶解作用起建设性作用。

Kumukuli Basin is a tertiary dominated depositional basin.It is between Qimatage Mountain and East Kunlun Aerjin Mountain,in the form of delta,and it's widest place is about 255km in the west.It covers 1.6×104 km2.The reservoir of Kumukuli mainly is feldspathic lithic sandstone,lithic feldspathic sandstone and little lithic sandstone.The reservoir sandstone is typical low porosity and low permeability.Based on core observation,and by using thin section observation,scanning transmission electron microscope observation,cathodolum inesconce and physical property,it is considered that the sandstone of Kumukuli Basin goes through the compaction,cementation,metasomasis,solution and split during the diagenesis.And now it is at the late diagenesis stage.During the diagenesis evolution,most original porosity of the reservoir sandstone of Xujiahe Formation is destroyed.In the porosity evolution,the compaction and the cementation are mainly of destruction,the solution is of construction.