川中古隆起北斜坡寒武系龙王庙组油气成藏特征及演化模式  

Characteristics and evolution model of hydrocarbon accumulation of Cambrian Longwangmiao Formation in the north slope of central Sichuan paleo-uplift

作　　者：卢科良 吴康军 李志军 孙永河 徐少华 梁锋[3] 刘露 李爽 LU Keliang;WU Kangjun;LI Zhijun;SUN Yonghe;XU Shaohua;LIANG Feng;LIU Lu;LI Shuang(School of Petroleum Engineering,Chongqing University of Science and Technology,Chongqing 401331,China;Chongqing Key Laboratory of Complex Oil&Gas Field Exploration and Development,Chongqing 401331,China;Central Sichuan Oil and Gas District,PetroChina Southwest Oil&Gas Field Company,Suining 629000,Sichuan,China)

机构地区：[1]重庆科技大学石油与天然气工程学院,重庆401331 [2]复杂油气田勘探开发重庆市重点实验室,重庆401331 [3]中国石油西南油气田分公司川中油气矿,四川遂宁629000

出　　处：《岩性油气藏》2024年第4期159-168,共10页Lithologic Reservoirs

基　　金：重庆市自然科学基金创新发展联合基金(重点项目)“复式断陷盆地断裂分段生长机制及对油气成藏与开发的控制作用研究”(编号:CSTB2022NSCQ-LZX0020);重庆市教委科学技术研究项目“川中古隆起北斜坡龙王庙组沥青成因及其油气勘探意义”(编号:KJQN202201549);重庆科技大学研究生科技创新训练计划项目“川中古隆起北斜坡龙王庙组断裂演化及其控藏机理”(编号:YKJCX2220104)联合资助。

摘　　要：利用测井、录井、岩心分析化验等资料,对川中古隆起北斜坡下寒武统龙王庙组油气成藏条件、油气充注特征及成藏演化模式展开了深入研究。研究结果表明:(1)川中古隆起北斜坡下寒武统龙王庙组天然气具备良好的成藏条件,下伏筇竹寺组烃源岩在北斜坡腹部及西侧裂陷槽存在2个生烃中心,其TOC平均值分别为1.90%和3.46%,有机质以Ⅰ型干酪根为主,可提供充足且优质的烃源;龙王庙组内部发育的颗粒滩体岩溶储层与上覆高台组厚层致密泥质云岩,构成了优势储-盖组合;区内广泛发育的油源断裂可作为纵向优势运移通道高效输导油气。(2)研究区龙王庙组具3期成藏特征:晚三叠世末期(约214~206 Ma)发生第1期充注,大量成熟油聚集形成古油藏;早侏罗世末期(约193~186 Ma)发生第2期充注,表现为“多油少气”混合充注;中侏罗世末期(约170~164 Ma)发生第3期充注,大量油裂解气充注储层并聚集形成现今气藏。(3)研究区龙王庙组油气成藏演化可划分为4个阶段:加里东早期—二叠纪前少量低熟油充注阶段、二叠纪—三叠纪大量成熟油充注形成古油藏阶段、中侏罗世—白垩纪古油藏被破坏形成裂解气藏阶段以及晚白垩世至今气藏调整阶段。Based on logging,well log,core analysis and laboratory data,a study was conducted on the hydro‐carbon accumulation conditions,hydrocarbon filling characteristics,and accumulation evolution model of Lower Cambrian Longwangmiao Formation in the north slope of central Sichuan paleo-uplift.The results show that:(1)The natural gas of Lower Cambrian Longwangmiao Formation in the north slope of central Sichuan paleo-uplift has good hydrocarbon accumulation conditions.The source rocks of underlying Qiongzhusi Forma‐tion have two hydrocarbon generation centers in the central and western rift troughs of the north slope,with an average TOC of 1.90%and 3.46%,respectively.The organic matter is mainly typeⅠkerogen,which can provide sufficient and high-quality hydrocarbon sources.The grain-shoal karst reservoirs developed within Longwang‐miao Formation and the dense argillaceous dolomites of the overlying the Gaotai Formation form a dominant reservoir-cap assemblage.The widely developed oil-source faults in the study area can serve as vertically domi‐nant migration channels for efficient hydrocarbon migration.(2)The Longwangmiao Formation in the study area has three stages of hydrocarbon accumulation characteristics:The first stage of filling occurred at the end of Late Triassic(approximately 214-206 Ma),with a large amount of mature oil accumulating to form paleo-oil reser‐voirs.In the late Early Jurassic(approximately 193-186 Ma),the second stage of filling occurred,characterized by a mixed filling of more oil and less gas.At the end of the Middle Jurassic(approximately 170-164 Ma),the third stage of filling occurred,with a large amount of oil cracked gases filling the reservoir and accumulating to form the current gas reservoir.(3)The hydrocarbon accumulation evolution of Longwangmiao Formation in the study area can be divided into four stages:the early Caledonian to pre Permian stage with a small amount of low mature oil filling,the Permian to Triassic stage with a large amount of mature oil filling to form anci

关 键 词：颗粒滩体岩溶储层 泥质云岩盖层 储-盖组合 油源断裂 古油藏 混合充注 裂解气 龙王庙组 寒武系 北斜坡 川中古隆起 

分 类 号：TE122.1[石油与天然气工程—油气勘探] P618.13[天文地球—矿床学]