天然气勘探与开发2025，Vol.48Issue(3)：85-96,12.DOI:10.12055/gaskk.issn.1673-3177.2025.03.009
川中地区龙女寺区块茅口组气藏开发有利区优选
Optimization of favorable zones for gas reservoir development in Maokou Formation of Longnvsi block,central Sichuan Basin
摘要
Abstract
The Middle Permian Maokou Formation gas reservoirs in the Longnvsi block of the central Sichuan Basin are characterized by thin reservoir thickness,strong heterogeneity,low porosity and permeability in matrix,making it difficult to optimize favorable zones,which severely impedes the efficient development of the reservoirs.To address the challenge,the reservoir classification characteristics and high-quality reservoir development models were clarified,by deeply analyzing the actual drilling data,distribution patterns of beaches,and presedimentary paleogeomorphy.Combined with the main controlling factors of gas well productivity,a method for optimizing favorable zones in thin reservoirs with strong heterogeneity was formed,and two types of favorable zones selected.The proposed method was verified in subsequent wells.The research results are obtained in four aspects.First,the Maokou Formation gas reservoirs are divided into fractured-vuggy,vuggy,and porous types,with the first two being high-quality reservoirs.Second,two high-quality reservoir development models,i.e.high-energy beach+paleogeomorphic slope,and high-energy beach+paleogeomorphic highland,are established.Combined with the seismic response characteristics of"double wave peak"or"lower strong complex wave"from drilled wells,it is predicted that high-quality reservoirs are mainly developed near Wells MX145 and MX039-H1,with an average thickness of 4.1 m.Third,gas well productivity is primarily controlled by high-quality reservoir type,thickness,and fracture development degree.Gas wells in well-developed fractured-vuggy reservoirs with greater thickness generally reveal higher productivity.Fourth,the favorable zones of the reservoirs can be categorized into two classes,covering a total area of 429.66 km2.Dominated by fractured-vuggy reservoirs,the Class I exhibits strong dolomitization in reservoir,high-quality reservoir thickness exceeding 4 m,stable well production no less than 20×104 m3/d,and dynamic gas reserves no less than 20×108 m3.Dominated by vuggy reservoirs,the Class II shows moderate to strong dolomitization in reservoir,high-quality reservoir thickness of 2-4 m,stable well productivity of 10×104-20×104 m3/d,and dynamic gas reserves less than 20×108 m3.The proposed method of favorable zone optimization for the development of gas reservoirs with thin thickness and strong heterogeneity can provide ideas and references for the efficient development of similar gas reservoirs.关键词
四川盆地中部/龙女寺区块/二叠系中统茅口组/优质储层/白云石化作用/薄储层/强非均质性/天然气开发/有利区优选Key words
Central Sichuan Basin/Longnvsi block/Middle Permian Maokou Formation/High-quality reservoir/Dolomitization/Thin reservoir/Strong heterogeneity/Natural gas development/Optimization of favorable zone引用本文复制引用
李文,杨东凡,李滔,兰雪梅,惠栋,闫梦楠,张锐铎,徐睿..川中地区龙女寺区块茅口组气藏开发有利区优选[J].天然气勘探与开发,2025,48(3):85-96,12.基金项目
四川省自然科学基金项目(编号:2023NSFSC0261). （编号:2023NSFSC0261）
