摘要
文中以地震、钻井、岩心、气体组分及同位素等资料为基础,分析了川西地区不同构造中三叠统雷口坡组的气藏特征,划分了天然气来源,明确了油气成藏模式。研究表明:根据天然气组分特征差异,可将川西地区雷口坡组气藏划分为烷烃体积分数略低、H2S和CO_(2)等非烃体积分数略高的山前隐伏构造带,以及烷烃体积分数略高、H2S和CO_(2)等非烃体积分数略低的山前坳陷带;根据天然气烷烃同位素特征差异,山前隐伏构造带可划分为δ13C2偏轻、同位素倒序分布的石羊镇、鸭子河构造和δ13C2偏重、同位素正序分布的金马构造;山前坳陷带可划分为δ13C2偏轻、碳同位素值正序分布的新场构造和δ13C2偏重、碳同位素值正序分布的永兴、马井构造。基于天然气运移条件和成藏模式分析认为:石羊镇、鸭子河构造天然气来源于龙潭组和雷口坡组烃源岩;金马、马井构造天然气来源于龙潭组、雷口坡组和马鞍塘组烃源岩;新场构造天然气来源于雷口坡组烃源岩,顶部部分层段由马一段石灰岩供烃;永兴构造天然气来源于马二段页岩。油气成藏模式和断层发育规模是控制川西地区不同构造雷口坡组气藏特征及天然气来源差异的主要因素。
Based on seismic,drilling,core,gas composition and isotope data,the characteristics of gas reservoirs in Leikoupo Formation of the middle Triassic of different structures in western Sichuan Basin are analyzed.Natural gas sources are classified,and the hydrocarbon accumulation model is clarified.The research shows that according to the difference of natural gas composition,the Leikoupo Formation gas reservoirs in western Sichuan Basin can be divided into two categories,namely,the piedmont concealed structural belt with slightly low alkane volume fraction,slightly high H2S and CO_(2) non-hydrocarbon volume fraction,and the piedmont depression zone with slightly high alkane volume fraction and slightly low H2S and CO_(2) non-hydrocarbon volume fraction.According to the difference of natural gas alkane isotope characteristics,the piedmont concealed structural belt can be divided into the structure of Shiyangzhen and Yazihe with lighterδ13C2 and isotopes in reverse order,and Jinma structure with heavierδ13C2 and positive isotope distribution.The piedmont depression zone can be divided into Xinchang structure with lighterδ13C2 and isotope positive distribution,and Yongxing and Majing structures with heavierδ13C2 and positive isotope distribution.Based on the analysis of natural gas migration conditions and accumulation models,it is believed that the natural gas in Shiyangzhen and Yazihe structures comes from the source rocks of Longtan Formation and Leikoupo Formation.The natural gas of Jinma and Majing structures comes from the source rocks of Longtan Formation,Leikoupo Formation and Maantang Formation.The natural gas of Xinchang structure mainly comes from the source rocks of Leikoupo Formation,and some parts of the top structure have the limestone of the first Member of Maantang Formation as their hydrocarbon supply.The natural gas of Yongxing comes from the shale source rocks of the second Member of Maantang Formation.Oil and gas accumulation models and the scale of fault development are the main factors controlling the difference of gas reservoir characteristics and natural gas sources in different structures of Leikoupo Formation in western Sichuan Basin.
作者
李智
李双建
王濡岳
张磊
崔一鑫
LI Zhi;LI Shuangjian;WANG Ruyue;ZHANG Lei;CUI Yixin(Petroleum Exploration and Production Research Institute,SINOPEC,Beijing 102206,China;Key Laboratory of Geology and Resources in Deep Stratum,SINOPEC,Beijing 102206,China)
出处
《断块油气田》
CAS
CSCD
北大核心
2024年第2期299-307,325,共10页
Fault-Block Oil & Gas Field
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”(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”(U19B6003)。
关键词
同位素特征
运移条件
成藏模式
雷口坡组
川西地区
isotopic characteristics
migration conditions
accumulation model
Leikoupo Formation
western Sichuan Basin
作者简介
第一作者:李智,男,1989年生,助理研究员,博士,从事盆地构造解析及石油地质综合研究。E-mail:lizhicug@163.com。;通信作者:王濡岳,男,1990年生,高级工程师,博士,从事非常规油气地质与油气勘探规划研究。E-mail:wry1990@vip.qq.com。
