摘要
四川盆地北部须家河组须四段为辫状河三角洲前缘沉积,砂体极其发育,而因须四段整体埋深大、储层非均质性强、孔隙结构复杂,储层“甜点”识别和综合评价成为制约该区低渗透致密砂岩储层勘探开发的关键。基于大量薄片观察鉴定,结合测井、录井资料,分析了控制特低渗透致密砂岩储层的关键地质因素,提出因子分析法定性识别致密砂岩储层“甜点”模型和定量评价标准,并对四川盆地北部目标区块须四段储层进行综合评价。结果证实:①致密砂岩储层局部存在物性较好的“甜点”区;②因子分析法提取的3个参数因子能定性解释致密砂岩储层特征,准确识别“甜点”段;③因子分析法定量评价结果与四川盆地北部须四段实际勘探开发效果吻合,相对于常规评价方法准确率大幅提高;④川北地区须四段储层可划分为三类,目标区块主要发育Ⅱ类储层,该区块东南部北东向为天然气富集区,是气藏开发的重点区域。
Located in the north of the Sichuan Basin,the 4th Member of Xujiahe Formation features braided-river,delta-front deposits,and extremely developed sand body.Due to the large burial depth,strong reservoir heterogeneity,and complex pore structure,the exploration and development of low permeability tight sandstone gas reservoir are greatly constrained by the identification and comprehensive evaluation of"sweet spots".Based on the extensive observation and identification of thin-section and in reference to logging data,this paper analyzes the key geological factors controlling the ultra-low permeability tight sandstone gas reservoir,puts forward a qualitative"sweet spots"identification model based on factor analysis for tight sandstone gas reservoir,and conducts comprehensive evaluation of the 4th Member of Xujiahe Formation in the target block in northern Sichuan Basin.The results show,①"Sweet spots"region with good physical properties exists in some areas of tight sandstone gas reservoir;②The three parameter factors extracted by the factor analysis can qualitatively explain the characteristics of tight sandstone gas reservoir and accurately identify the"sweet spots"section;③The quantitative evaluation results of the factor analysis are in good agreement with the actual exploration and development effect of the 4th Member of Xujiahe Formation in northern Sichuan Basin,and are much more accurate than those of the common evaluation methods;④Reservoir of the 4th Member of Xujiahe Formation in North Sichuan can be divided into three types,and the target block has mostly developed type Ⅱ reservoir,and the key area of gas reservoir development rests in the NE trending gas-rich region in the southeastern part of the block.
作者
周林
刘皓天
周坤
郝景宇
汪鑫
Zhou Lin;Liu Haotian;Zhou Kun;Hao Jingyu;Wang Xin(Exploration and Production Research Institute,Jianghan Oilfield Company,SINOPEC,Wuhan 430223,China;Northeast Sichuan Gas Field,Southwest Oil&Gas Field Company,PetroChina,Dazhou Sichuan 635000,China;SINOPEC Exploration Company,Chengdu 610041,China;Oil and Gas Development Department of Center Tarim,Oilfield Company,PetroChina,Korla Xinjiang 841000,China)
出处
《地质科技通报》
CAS
CSCD
北大核心
2020年第4期165-173,共9页
Bulletin of Geological Science and Technology
基金
国家科技重大专项(2016ZX05002-004-011)
四川省基础应用研究项目(2017JY0176)。
关键词
甜点
识别
综合评价
致密砂岩
因子分析
须四段
sweet spot
identification
comprehensive evaluation
tight sandstone
factor analysis
the 4th Member of Xujiahe Formation