川西地区雷口坡组储层流体包裹体特征与成藏期次  

Characteristics of fluid inclusions and hydrocarbon accumulation periods of Leikoupo Formation in western Sichuan Basin

作　　者：李智 林会喜[1,2,3] 李双建 王濡岳 袁玉松[1,2,3] 李英强 Li Zhi;Lin Huixi;Li Shuangjian;Wang Ruyue;Yuan Yusong;Li Yingqiang(State Energy Key Laboratory for Carbonate Oil and Gas,Beijing 102206;SINOPEC Key Laboratory of Geology and Resources in Deep Stratum,Beijing 102206;SINOPEC Petroleum Exploration and Production Research Institute,Beijing 102206)

机构地区：[1]国家能源碳酸盐岩油气重点实验室,北京102206 [2]中国石化深部地质与资源重点实验室,北京1022061 [3]中国石化石油勘探开发研究院,北京102206

出　　处：《地质科学》2024年第3期781-791,共11页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家自然科学基金企业重点联合基金项目“盆地深部地质作用过程与资源效应”(编号:U20B6001);国家自然科学基金企业创新发展联合基金项目“海相深层油气富集机理与关键工程技术基础研究”(编号:U19B6003)资助。

摘　　要：以地震、钻井、岩心和包裹体薄片等资料为基础,结合区域构造演化和烃源岩生排烃过程,通过对川西地区中三叠统雷口坡组储层流体包裹体岩相学分析、均一温度及盐度测定、埋藏—热演化史模拟和气藏演化过程分析等,明确雷口坡组油气充注时间和期次,分析不同类型气藏的成藏过程。结果表明:川西探区雷口坡组包裹体成群/成带发育于孔洞矿物充填期后,丰度较低(GOI为1%±),均为灰色—深灰色含烃盐水包裹体;均一温度在90℃~200℃,温度峰值在120℃~150℃;盐度分布在0~24%,具体可细分为0~4%、6%~18%和20%~24%共3个区间。川西探区雷口坡组天然气主成藏期有3期,分别为晚三叠世末期、早侏罗世晚期至晚侏罗世早期和新近纪—第四纪。油气成藏过程为晚三叠世,上二叠统龙潭组和中三叠统雷口坡组烃源岩进入生油高峰,生成原油沿印支运动形成的断裂进入雷四段储层形成古油藏;早-中侏罗世,两套烃源岩进入生气高峰,叠加古油藏裂解生气形成气藏,斜坡区马鞍塘组烃源岩进入生油高峰,沿不整合面侧向运移至雷四段储层形成古油藏;新近纪以来,油气藏最终调整定型形成现今形态。Based on seismic,drilling,core and inclusion thin sections data,combined with regional tectonic evolution and hydrocarbon generation and expulsion processes of source rocks,this study analyzes the fluid inclusion petrology,uniform temperature and salinity measurement,burial thermal evolution history simulation,and gas reservoir evolution process analysis of the Leikoupo Formation reservoir in the western Sichuan exploration area.It clarifies the oil and gas filling time and period of the Leikoupo Formation,and analyzes the formation process of different types of gas reservoirs.The results show that the Leikoupo Formation inclusions in the western Sichuan exploration area develop in groups/zones after the filling period of pore minerals,with low abundance(GOI of 1%±),and are all gray-dark gray hydrocarbon containing saline inclusions;the uniform temperature is between 90℃~200℃,and the temperature peak is between 120℃~150℃;the salinity distribution is between 0~24%,which can be further divided into three intervals:0~4%,6%~18%and 20%~24%.There are three main periods of natural gas accumulation in the Leikoupo Formation of the western Sichuan exploration area,namely the Late Triassic,late Early Jurassic to early Late Jurassic,and Neogene Quaternary.The process of oil and gas accumulation is that the source rocks of the Longtan Formation of the Upper Permian and the Leikoupo Formation of the Middle Triassic entered the peak of oil generation in the Late Triassic,and the crude oil was generated along the faults formed by the Indosinian movement and entered the 4th member of Leikoupo reservoir to form an ancient oil reservoir;in the Early to Middle Jurassic,two sets of source rocks entered a peak of gas generation,superimposed with the cracking of ancient oil reservoirs to form oil and gas reservoirs;the source rocks of the Maantang Formation in the slope area entered the peak of oil generation and migrated laterally along the unconformity to the 4th member of Leikoupo reservoir,forming an ancient oil reservoir

关 键 词：岩相学特征 均一温度 盐度 成藏期次 成藏过程 雷口坡组 川西探区 

分 类 号：P618.13[天文地球—矿床学]