A new model for predicting irreducible water saturation in tight gas reservoirs

作     者：Yu-Liang Su Jin-Gang Fu Lei Li Wen-Dong Wang Atif Zafar Mian Zhang Wei-Ping Ouyang Yu-Liang Su;Jin-Gang Fu;Lei Li;Wen-Dong Wang;Atif Zafar;Mian Zhang;Wei-Ping Ouyang

作者机构：School of Petroleum EngineeringChina University of Petroleum(East China)Qingdao 266580ShandongChina Department of Petroleum TechnologyUniversity of KarachiKarachiPakistan Changqing Downhole Technology CompanyChuanqing Drilling Engineering Co.LtdCNPCXi’an 710018ShaanxiChina 

出 版 物：《Petroleum Science》 (石油科学（英文版）)

年 卷 期：2020年第17卷第4期

页      面：1087-1100页

核心收录：

学科分类：081803[工学-地质工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：supported by the National Science Foundation (51904324, 51674279, 51804328) the Major National Science and Technology Project (2017ZX05009-001, 2017ZX05072) the Key Research and Development Program (2018GSF116004) the China Postdoctoral Science Foundation (2019T120616) the Funding for Scientific Research of China University of Petroleum East China (YJ20170013) Graduate Innovative Engineering project (YCX2019023) 

主　　题：Fractal theory Stress dependence effect Capillary model Tight sandstone gas reservoir Irreducible water saturation 

摘      要：The irreducible water saturation(Swir) is a significant parameter for relative permeability prediction and initial hydrocarbon reserves ***,the complex pore structures of the tight rocks and multiple factors of the formation conditions make the parameter difficult to be accurately predicted by the conventional methods in tight gas *** this study,a new model was derived to calculate Swir based on the capillary model and the fractal *** model incorporated different types of immobile water and considered the stress *** dead or stationary water(DSW) was considered in this model,which described the phenomena of water trapped in the dead-end pores due to detour flow and complex pore *** water film,stress effect and formation temperature were also considered in the proposed *** results calculated by the proposed model are in a good agreement with the experimental *** proves that for tight sandstone gas reservoirs the Swir calculated from the new model is more *** irreducible water saturation calculated from the new model reveals that Swir is controlled by the critical capillary radius,DSW coefficient,effective stress and formation temperature.