天然气勘探与开发2023，Vol.46Issue(4)：27-34,8.DOI:10.12055/gaskk.issn.1673-3177.2023.04.003
川中地区中二叠统茅口组白云岩储层特征及发育主控因素
Dolomite reservoirs of the Middle Permian Maokou Formation,central Sichuan Basin:Characteristics and main influential factors
摘要
Abstract
There developed varying dolomitized reservoirs in the Middle Permian Maokou Formation,central Sichuan Basin,in which significant gas discoveries have been made recently.Thus,the reservoir characterization,the enquiry of dolomitization mechanisms and the identification of main controls are very meaningful tasks for next exploration and deployment.Based on the macroscopic and microscopic observation on cores and outcrop samples,as well as some analysis on geochemical features,the characteristics,genesis and main controlling factors were investigated for the dolomite reservoirs.Results show that(i)these Maokou reservoirs in central basin are developed in the upper Maokou 2 Member,which are featured by stable lateral extension,and they are dominated by fine to medium crystalline residual sand-calstic dolomite,bioclastic dolomite,and dolomitic limestone.And there exist three reservoir types,for example,dolomite porous reservoirs,dolomite fractured-vuggy and limestone porous ones;(ii)a diagenetic sequence has been es-tablished according to petrological and mineral characteristics along with contact relationship.Eight diagenetic episodes were identi-fied,including contemporaneous exposure dissolution,contemporaneous dolomitization,shalllow-burial dolomitization,shallow-burial silicification,Dongwu dolomitization,Indosinian hydrothermal dissolution,Indosinian thermal silicification,and deep-burial dissolu-tion;and(iii)for the dolomite reservoirs of Maokou Formation in the study area,both extension and distribution are jointly controlled by platform-margin high-energy beach,early exposure dissolution and dolomitization.Both later hydrothermal dissolution and burial dissolution are conducive to reforming reservoirs.关键词
川中地区/二叠系茅口组/白云岩/成岩序列/同生期暴露溶蚀/白云石化/台缘滩/早期白云石化Key words
Central Sichuan Basin/Permian Maokou Formation/Dolomite/Diagenetic sequence/Contemporaneous exposure dissolu-tion/Dolomitization/Platform-margin beach/Early dolomitization引用本文复制引用
山述娇,陈聪,张玺华,谢忱,陈延贵,徐正华..川中地区中二叠统茅口组白云岩储层特征及发育主控因素[J].天然气勘探与开发,2023,46(4):27-34,8.基金项目
中国石油天然气集团有限公司科技项目"风险勘探领域和目标研究、工程技术攻关及现场试验"资助项目(编号:2023YQX10104). （编号:2023YQX10104）
