古地理学报2025，Vol.27Issue(3)：696-713,18.DOI:10.7605/gdlxb.2025.028
川东地区侏罗系自流井组东岳庙段陆相页岩岩相类型及储集层特征
Lithofacies types and reservoir characteristics of continental shale in the Dongyuemiao Member of Jurassic Ziliujing Formation,eastern Sichuan Basin
摘要
Abstract
The physical properties of shale reservoirs are crucial to the enrichment mechanism of shale oil and gas.This study focuses on investigating the reservoir's physical properties and the key factors controlling various lithofacies of continental shale in the Jurassic Dongyuemiao shale in the eastern Sichuan Basin.On the basis of lithofacies division,the research employs core observation,scanning electron mi-croscope,low-temperature nitrogen adsorption,and other methods to analyze the reservoir space type,physical properties,and the primary controlling factors.The study findings reveal that:(1)The Dongyuemiao Member shale in the eastern Sichuan Basin are primarily composed of clay minerals and quartz,followed by calcite,and minor amounts of feldspar,dolomite,pyrite,and rhodochrosite.Four main lithofacies are identified in the study area:high-medium total organic carbon(TOC)argillaceous shale(Ⅰ2),medium TOC and TOC bearing mixed shale(Ⅱ1),medium-low TOC silt(argillaceous)mixed shale(Ⅱ2),and low TOC and TOC bearing argillaceous siltstone(Ⅲ2).(2)The shale reservoir space is mainly composed of micropores and microfractures.The micropores are dominated by intergranular pores between clay minerals,followed by pores within organic matter and,locally,shell dissolution pores.Microfractures mainly include bedding fractures and edge fractures around shell fragments.(3)High organic matter abundance(＞1％),high content of clay minerals(＞40％),and moderate carbonate mineral content(8％～12％)in the shale of the study area are conducive to pore development.In contrast,high quartz and feldspar mineral content(＞50％)and either excessive or insufficient car-bonate mineral content(＞12％or＜8％)hinder shale pore development.(4)Among the lithofacies types,the medium-low TOC silty(argillaceous)mixed shale(Ⅱ2)is the most favorable for reservoir de-velopment,followed by high-medium TOC argillaceous shale(Ⅰ2).The medium TOC and TOC bearing mixed shale(Ⅱ1)is less favorable,while the low TOC and TOC bearing argillaceous siltstone(Ⅲ2)is the least favorable.Based on the vertical distribution of lithofacies,the middle to upper intervals of the Dong 2 sub-member are identified as the most favorable reservoir development zones in the study area.关键词
陆相页岩/岩相类型/储集层特征/东岳庙段/川东地区Key words
continental shale/lithofacies types/reservoir characteristics/Dongyuemiao Member/eastern Sichuan Basin分类
天文与地球科学引用本文复制引用
陈旺,周红飞,王兴志,韦明洋,曾德铭,康家豪,李阳,刘凯铭,李钥,洪海涛..川东地区侏罗系自流井组东岳庙段陆相页岩岩相类型及储集层特征[J].古地理学报,2025,27(3):696-713,18.基金项目
中国石油—西南石油大学创新联合体项目(编号:2020CX050000)和四川省自然科学基金重点项目(编号:24NSFSC0093)联合资助.Co-funded by the Innovation Consortium Project between China National Petroleum Corporation and Southwest Petroleum University(No.2020CX050000)and the Natural Science Foundation of Sichuan Province(No.24NSFSC0093) （编号:2020CX050000）
