断背斜储层物性演化及流固耦合数值模拟OA北大核心

To better study the effects of structural strain and fluid overpressure on reservoir properties,this research focuses on the thrust-related folds in the Kelasu Structural Belt,Kuqa Depression.The in-tergranular volume distribution characteristics of the reservoir and a fluid-solid coupling numerical meth-od are applied to analyze the formation process and property evolution of the faulted anticline.The study quantitatively evaluated the controlling effects of tectonic compression and fluid flow on the evolution of reservoir physical properties.The results showed that during the formation of a fault-related anticline on Kelasu Structural Belt,Kuqa Depression,the reservoir formation would be under compressive strain.Due to the stretching of the outer-arc of an anticline and associated thrust faulting,the hinge and back-limb of the fault-related anticline would become favorable reservoirs with relatively high porosity.In the late-stage,tectonic compression-induced overpressure would provide little protection on reservoir porosi-ty,with merely 0.25％-0.47％ and 0.18％-0.43％ increases at the hinge and back-limb of the fault-re-lated anticline,respectively.The evolution paths of the compressive strain controlled the porosity evolu-tion of the reservoir.Early-stage strong compressive strain may cause a rapid decrease of porosity,while the late-stage outer-arc tensile can partially offset of the compressive strain.The porosity loss of the res-ervoir during the early-stage compression cannot be fully restored.This study provides a theoretical ba-sis for predicting the distribution of high-quality reservoirs on the fault-related anticline under the com-pressional tectonic condition.