超深层复杂岩溶型底水气藏高产稳产主控因素——以安岳气田GS1井区灯二段气藏为例  

Main factors controlling high and stable production of ultra-deep complex karst bottom-water gas reservoirs:A case study of gas reservoir of Deng 2 Member,GS1 well block,Anyue gas field

作　　者：申艳 施延生[1,3] 刘耘 陈洋 孙启蒙 苏琛[1,2] 王俊杰 鄢友军 SHEN Yan;SHI Yansheng;LIU Yun;CHEN Yang;SUN Qimeng;SU Chen;WANG Junjie;YAN Youjun(National Energy R&D Center of High Sulfur Gas Exploitation,Chengdu,Sichuan 610051,China;Exploration and Development Research Institute,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610041,China;Sichuan Kelite Oil and Gas Technological Service Company,Ltd.,Chengdu,Sichuan 610041,China)

机构地区：[1]国家能源高含硫气藏开采研发中心 [2]中国石油西南油气田公司勘探开发研究院 [3]四川科力特油气技术服务有限公司

出　　处：《天然气勘探与开发》2023年第3期59-66,共8页Natural Gas Exploration and Development

基　　金：国家科技重大专项“四川盆地大型碳酸盐岩气田开发示范工程”(2016ZX05052);四川省自然科学基金项目“超高压特低孔强非均质碳酸盐岩气藏有效储层物性下限研究”(编号:2023NSFSC0261)项目。

摘　　要：安岳气田GS1井区震旦系上统灯影组二段为四川盆地目前重点开发层系,该气藏为典型超深层低孔复杂岩溶型底水气藏,埋深超5000 m,储层平均孔隙度为3.2%,受丘滩相沉积和多期岩溶作用共同影响,储层非均质性强,气井产能差异大,且底水广泛发育,气藏高产稳产面临重大挑战。为此,综合测井、地质、动态等资料,系统开展优质储层特征研究,明确气藏高产稳产主控因素。研究结果表明:①GS1井区灯二段储层分为孔洞型、裂缝-孔洞型及孔隙型3种类型,其中孔洞型和裂缝-孔洞型为优质储层;②优质储层发育主要受沉积和成岩作用控制,沉积作用是优质储层形成的基础,岩溶作用控制了优质储层的品质;③气井高产稳产受优质储层规模、开发井型、避水高度等因素的多重影响,优质储层越发育气井产能越高,水平井可大幅提高气井产能,且合理的无因次避水高度为0.4。该研究成果为安岳气田GS1井区灯二段气藏开发井部署提供了可靠依据,为气藏高效开发奠定了基础。The second member of Upper Sinian Dengying Formation(Deng 2 Member)in the GS1 well block of the Anyue gas field is currently a key development stratum in the Sichuan Basin.Gas reservoir in it shows typical characteristics of an ultra-deep low-po-rosity complex karst bottom-water reservoir,with the burial depth exceeding 5000 m and average porosity of 3.2%.Influenced by both the deposition of mound-beach facies and multi-period karstification,the reservoir exhibits strong heterogeneity,varying well produc-tivity,and widespread occurrence of bottom water,posing huge challenges to high and stable production.To address these challenges,a systematic study was conducted on the characteristics of high-quality reservoirs based on well logging,geological,and dynamic data to identify the key factors controlling high and stable production.The following results are obtained:(i)Reservoirs in the Deng 2 Member can be classified into three types,i.e.vuggy,fractured-vuggy,and porous,of which the vuggy and fractured-vuggy reservoirs reveal high quality.(ii)The development of high-quality reservoirs is controlled mainly by sedimentation and diagenesis,the former is a fundament forming reservoir,and the karstification in the latter decides reservoir quality.(iii)High and stable production of gas well is influenced by multiple factors,including the scale of high-quality reservoirs,type of development well,and water avoidance height.The more developed the high-quality reservoirs,the higher the well productivity.Horizontal wells can significantly improve gas pro-ductivity,and the rational dimensionless height of water avoidance is determined to be 0.4.These research findings provide reliable guidance for deploying development wells in the Deng 2 Member of the GS1 well block,and lay a foundation for efficient develop-ment of gas reservoir.

关 键 词：安岳气田 灯影组 底水气藏 优质储层 高产稳产 主控因素 岩溶作用 避水高度 

分 类 号：P618.13[天文地球—矿床学]