广安地区须家河组须六段储层控制因素研究

Study on Xu-6 Reservoir Controlling Factors of Xujiahe Formation in Guang’an Area

广安地区须家河组须六段是河流相沉积。储层物性以三角洲平原水上分支主河道为最好。储集岩类以长石砂岩和岩屑砂岩为主,总体具有低孔、低渗的特征。其储集空间以原生成因的残余粒间孔为主,其次为次生成因的粒间和粒内溶孔。研究表明,沉积作用对储层的影响主要通过对砂体展布与厚度、岩石组构、物性等方面的控制来体现,经过强烈的压实、压溶和胶结作用改造后,储层的物性明显降低,而埋藏期的长石颗粒的溶蚀使得储集空间变好。

The Xu-6 reservoir of Xujiahe formation in Guang＇an area are fluvial sendiments, and the reservoir with best physical property are developed on the main branch river channel of the deltaplain. The reservoir rocks are mainly arcose and lithic sandstone, which are of low porosity and low permeability characteristics. The reservoir spaces are mainly original residual intergranular pores, and the secondary intergranular or intragranular pores. The study shows that the affection on reservoir of sedimentation are mainly by the controlling of sand distribution, rock fabric and physical property and so on. The physical property obviously decreased by the reconstruction of intensely compaction, pressolution and cementation, but the dissolution of feldspar in buffed period improved the spaces.