天然气勘探与开发2025，Vol.48Issue(5)：70-80,11.DOI:10.12055/gaskk.issn.1673-3177.2025.05.007
不同气水组合模式下底水气藏水侵机理
Water invasion mechanisms of bottom-water gas reservoirs under different gas-water combinations
摘要
Abstract
In recent years,significant breakthroughs have been made in the exploration and development of the bottom-water gas reservoir in the second member of the Upper Sinian Dengying Formation(hereinafter referred to as Deng 2 Member),Penglai gas field,Sichuan Basin.These advancements have provided an important support for increasing gas reserves and production in this area.The multi-scale fractures and the nonuniformly distributed lithologic interlayers developed in the Deng 2 Member gas reservoir complicate the water invasion mechanisms,making it difficult to predict the water invasion dynamics in the early stage of development.Taking the Deng 2 Member gas reservoir as the research object,the water invasion characteristics of bottom-water gas reservoirs with developed multi-scale fractures and interlayers were revealed through indoor physical simulation experiments and theoretical analysis,and the limit of the critical flow pressure difference of multi-scale fractures was quantified.A chart for evaluating the sealing capacity of interlayers was constructed for the first time,identifying the water invasion risks in the Deng 2 Member gas reservoir.The results show that,(i)in the reservoirs with small-scale fractures developed,the bottom-water invasion exhibits typical"controllable and treatable"characteristics,and controlling the production pressure difference can effectively suppress nonuniform water invasion;the critical flow pressure difference required for water invasion in small-scale fractures is five times that in large-scale fractures;(ii)large-scale fractures are characterized by"more severe water invasion hazards and greater challenges in water control";the water breakthrough time is shortened by 1/9 and the recovery factor is reduced by 20%under the same pressure difference;additionally,the adjustable range of the critical pressure difference is limited,making water control development more challenging;and(iii)the sealing capacity of interlayers is jointly controlled by their physical properties,thickness and distribution characteristics;a quantitative evaluation chart for the sealing capacity of interlayers is constructed for the first time,which illustrates the vertical water-blocking effects of interlayers in different zones.It is concluded that the research results provide a beneficial guidance for the scientific and efficient development of bottom-water gas reservoirs in the Sichuan Basin.关键词
四川盆地蓬莱气田/震旦系上统灯影组二段/底水气藏/多尺度裂缝/临界压差/见水时间/隔夹层/水侵动态Key words
Penglai gas field of the Sichuan Basin/Deng 2 Member/Bottom-water gas reservoir/Multi-scale fracture/Critical pressure difference/Water breakthrough time/Interlayer/Water invasion dynamics分类
能源科技引用本文复制引用
杨玉斌,彭先,江俊,张春,戚涛,李秋,庞榆..不同气水组合模式下底水气藏水侵机理[J].天然气勘探与开发,2025,48(5):70-80,11.基金项目
中国石油天然气集团有限公司重大专项课题三"复杂碳酸盐岩气藏效益上产与提高采收率技术研究"(编号:2023ZZ16-03). （编号:2023ZZ16-03）
