探讨四川南江地区震旦系灯影组白云岩储集层的次生孔洞类型和孔洞充填物成因及特征。通过对次生孔洞充填矿物的形态、阴极发光、稳定同位素等特征的综合对比分析,现存储集空间都是与溶解作用和重结晶作用相关的晶间(溶)孔、粒间溶孔、特大溶孔和残余喀斯特孔洞等次生孔洞,可划分出第一世代纤柱状白云石→第二世代细-粗粒白云石→第三世代自形石英→第四世代他形石英→第五世代巨晶白云石的流体充注序列。孔洞充填矿物使得储集层内次生孔隙度显著降低,不利于灯影组古油藏的形成和保存。
This paper discusses about the secondary pore types and the characteristics of cave fillings in Sinian System Dengying Formation dolomite reservoir of Nanjiang area,Sichuan,China.The existing porosity types are basically secondary pores related to the dissolution and recrystallization,which are inter-crystal dissolution pores,inter-particle dissolution pores,great dissolution pores,and lots of relict karst cavities etc.According to the characteristics of the crystal shape,stable isotope and cathode luminescence of the cave fillings,multi-stage injection sequence of fluid can be reconstructed as follow: 1st generation fibrous-columnar dolomite→2nd generation fine-coarse crystal granular dolomite→3rd generation idiomorphic granular quartz→4th generation xenomorphic granular quartz→5th generation megacryst dolomite.The cave fillings are the main factors to make secondary pore spaces preserved hardly in reservoirs and unfavorable to the formation and preservation of ancient oil reservoirs.