四川盆地灯影组多类型流体多期次改造作用下孔隙度演化的定量研究OA北大核心CSTPCD

In this study,the fourth member of Dengying Formation in Sichuan Basin was examined.On the basis of traditional petrological testing,the reactive solute transport simulation technology was utilized to calculate the superposition and transfor-mation of reservoir pores due to multi-stage fluids and quantitatively restore the porosity evolution history.Results indicate that the reservoir experienced influences from atmospheric freshwater,seawater,organic acid,and hydrothermal fluid.The primary diagenetic processes controlling porosity were dissolution,dolomite formation and cementation,with transformed min-erals primarily comprising calcite,magnesium calcite,and dolomite.Different fluid types exhibited varying effects on reservoir reconstruction.Adequate atmospheric fresh water acted as a constructive fluid,while seawater,organic acids,and hydrother-mal fluids had both constructive and destructive impacts.Multi-stage fluids contributed to a superimposed effect on the reser-voir transformation,with the ultimate physical conditions of the reservoir contingent upon the comprehensive transformation of these fluids.Notably,the sequence of fluid modification significantly influenced the evolution of reservoir porosity.Simutane-ously,the sequence of fluid transformation played a pivotal role in shaping the evolution of reservoir porosity.