天然气勘探与开发2025，Vol.48Issue(3)：27-36,10.DOI:10.12055/gaskk.issn.1673-3177.2025.03.003
简阳地区须家河组四段致密气地质特征及富集高产主控因素
Geological characteristics and main controls on the enrichment and high yield of tight gas in Xujiahe 4 Member,Jianyang area,Sichuan Basin
摘要
Abstract
To figure out the main controls on the enrichment and high yield of tight gas in the fourth member of the Upper Triassic Xujiahe Formation(Xujiahe 4 Member)in Jianyang area,reservoir-forming conditions were discussed for tight gas in this member through the analysis of source-rock distribution,evaluation on reservoirs'physical properties,fault interpretation,and identification of source-reservoir assembly.Results show that(i)dominated by dark mud shale in the upper Xujiahe 3 and Xujiahe 5 members,source rocks in the study area are characterized by the total organic carbon content ranging from 0.32%to 71.40%and the hydrocarbon-generating intensity of(7-60)×108 m3/km2.And the assembly represents two features of lower source and upper reservoir as well as side source and side reservoir;(ii)for Xujiahe 4 reservoirs,as tight ones with extra-low porosity and permeability,the porosity changes from 6%to 8%and the permeability from 0.01 mD to 1 mD,respectively.And the mercury-injection curves reflect the median pore-throat radius of 1.08 μm,also indicating fine-throat porous reservoirs;(iii)Xujiahe 4 gas reservoirs whose production exceeds 20×104 m3/d in some high-yield wells and the absolute open flow achieves 50×104 m3/d belong to lithological trap gas reservoirs.There exists the positive correlation between fracture growth and fault throw vs.the distance to fault surface;and(iv)quality reservoirs are mostly extended in fracture zones associated with fourth-order faults(the ratio of fault throw to the distance to fault surface greater than 0.08),where the fracture openness has the angle smaller than 30º with the geostress direction.It is concluded that the superimposed zone of both predominant source below slope break belts and the fourth-order fault-controlled fractures is served as an optimal exploration target for Xujiahe gas reservoirs in Jianyang area.These above findings may provide theoretical foundation for fine exploration on tight gas reservoirs in the foreland slope of Sichuan Basin and thus allow for more rational exploration deployment.关键词
四川盆地简阳地区/三叠统上统须家河组/致密气/富集高产/气藏形成/主控因素/勘探有利区Key words
Jianyang area in Sichuan Basin/Upper Triassic Xujiahe Formation/Tight gas/Enrichment and high yield/Gas reservoir forming/Main control/Favorable exploration area引用本文复制引用
赵正望,邱玉超,李楠,郑超,金值民,杨强..简阳地区须家河组四段致密气地质特征及富集高产主控因素[J].天然气勘探与开发,2025,48(3):27-36,10.基金项目
中国石油天然气股份有限公司科技重大专项(编号:2021DJ210103). （编号:2021DJ210103）
