伊通盆地鹿乡断陷双阳组储层孔隙结构特征及其控制因素

通过对钻井岩芯及铸体薄片、扫描电镜观察,结合压汞分析测试,研究了伊通盆地鹿乡断陷双阳组储层的孔隙结构特征。结果表明:储层成因类型主要为扇三角洲砂体,部分为水下扇砂体;储层砂体孔隙类型以次生溶蚀孔隙为主,部分为原生粒间孔隙,具体可见粒内溶孔、原生粒间孔和粒间溶蚀扩大孔等;孔隙喉道较小,分选不好,连通性差,总体为低孔低渗型储层,其中,双阳组二段储层略好于双三段,双一段最差。双阳组储层孔隙结构特征主要受砂体成因类型和成岩作用的控制,此外,岩石粒度和构造作用也对孔隙结构有一定的控制作用。

Pore structure characteristics and controlling factors of Shuangyang Formation reservoir in Luxiang fault depression, Yitong Basin

Through the observation of drilling cores,casting slides and scanning electron microscope,combined with intrusive mercury analysis test,the authors studied the pore structure characteristics of Shuangyang Formation reservoir in Luxiang fault depression of Yitong Basin. The results show that the main genetic type of reservoir is fan-delta sand body,partly is underwater fan sand body. The main sand pore type is secondary solution pore, partly is primary intergranular pore,such as intragranular dissolution pore,primary intergranular pore and intergranular corrosion expansion pore. The reservoirs are low in porosity and permeability in general,with small pore throat,poor sorting and connectivity,on which,the second member of Shuangyang Formation is a little better than the third one,and the first one is the worst. The pore structure characteristics of Shuangyang Formation reservoir are mainly controlled by sand genetic types and diagenesis. In addition,particle size of rocks and tectonism also have some control actions to pore structure.