库车前陆盆地南斜坡西段油气成藏过程研究  

Study on hydrocarbon accumulation process in the western section of south slope of Kuqa foreland basin

作　　者：张昊 吕修祥[1,2] 王晓雪 李素梅[1,2] 朱毅秀[1,2] 蒲明宇 李燕琴 ZHANG Hao;LYU Xiuxiang;WANG Xiaoxue;LI Sumei;ZHU Yixiu;PU Mingyu;LI Yanqin(State Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum-Beijing,Beijing 102249,China;School of Geosciences,China University of Petroleum-Beijing,Beijing 102249,China;Research Institute of Petroleum Exploration&Development,Tarim Oilfield Company,PetroChina,Korla 841000,China)

机构地区：[1]中国石油大学(北京)油气资源与工程全国重点实验室,北京102249 [2]中国石油大学(北京)地球科学学院,北京102249 [3]中国石油塔里木油田公司勘探开发研究院,库尔勒841000

出　　处：《石油科学通报》2025年第1期35-50,共16页Petroleum Science Bulletin

基　　金：中国石油天然气股份有限公司塔里木油田公司重大科技专项(2017ZX05008)资助。

摘　　要：近年来,塔里木盆地库车坳陷勘探取得重大突破,但前人对于研究区的油气成藏过程研究比较薄弱。本文利用有机地球化学、流体包裹体等实验,结合盆地模拟技术,系统分析研究区原油来源、成藏期次和成藏过程。结果表明,研究区存在Ⅰ和Ⅱ两类原油,Ⅰ类英买力原油的三环萜类总体具有C_(19)<C20<C_(21)>C_(22)<C_(23)(升-降-升型)特征,碳同位素偏轻,油源对比指示其源岩为三叠系黄山街组烃源岩;而Ⅱ类却勒-羊塔-玉东原油三环萜类具有C_(19)>C20>C_(21)>C_(22)<C_(23)(降-降-升型)特征,碳同位素值偏重,油源对比指示源岩为侏罗系恰克马克组烃源岩。通过包裹体均一温度分布,结合单井埋藏史、热史及二维剖面模拟,分析认为Ⅰ类油为三叠系烃源岩生成的原油在16~5 Ma运移至古潜山储层聚集成藏;Ⅱ类油为侏罗系烃源岩生成的原油在5~2 Ma运移至白垩系、古近系聚集成藏。结合不同族群原油平面分布,推测两个成藏时期所形成的秋里塔格构造带褶皱区的分布是两类原油聚集成藏的主控因素:16~5 Ma时期秋里塔格构造带褶皱段致使研究区西部油气输导体系不畅通,所以Ⅰ类油藏分布于研究区东部;5~2 Ma时期秋里塔格构造带褶皱段致使研究区东部油气输导体系不畅通,致使Ⅱ类油藏分布于研究区西部。虽然秋参1井靠近烃源岩且在两个成藏期都处于油气运移路径上,但因为一直未发育有效圈闭导致失利;西秋2井因工程原因失利,研究发现,在该井潜山储层含油可能性较大,建议加深钻探。同时发现研究区烃源灶周缘西秋古隆起具备形成大型油气聚集带的条件。本文研究结果为该地区进一步勘探提供理论依据。In recent years,significant breakthroughs have been achieved in the exploration of the Kuqa Depression in the Tarim Basin.However,previous studies on the hydrocarbon accumulation process in the study area are relatively scarce.In this study,organic geochemistry,fluid inclusion experiments,and basin simulation techniques are employed to systematically analyze the source,accumulation period,and accumulation process of crude oil in the study area.The results show that two oil groups,namely Group Ⅰ and Group Ⅱ,can be identified in the study area.The tricyclic terpenoids of Group I crude oil follow the pattern of C_(19)<C_(20)<C_(21)>C_(22)<C_(23)(up-down-up type),and they have light carbon isotopes.The oil and source correlation indicates that their source rocks are the Huangshanjie Formation in the Triassic system.The tricyclic terpenoids of Group Ⅱ crude oil exhibit the pattern of C_(19)>C_(20)>C_(21)>C_(22)<C_(23)(down-down-up type),and the carbon isotope value is heavy.The oil-source correlation reveals that the source rock is the Jurassic Qiakemake Formation.Based on the distribution patterns of homogenization temperature,the evolutions of burial and thermal history,as well as the two-dimensional accumulation models of representative profiles,the results show that Group Ⅰ oils were generated from Triassic source rocks,migrated to the buried-hill reservoirs,and then accumulated between 16 and 5 Ma.Group Ⅱ oils originated from Jurassic source rocks,migrated to the Cretaceous strata,and then accumulated in the Cretaceous and Paleogene reservoirs between 5 and 2 Ma.The planar distributions of oil groups may be attributed to the distribution of fold areas in the Qiulitage tectonic belt,which formed in different periods.In the early period(16~5 Ma),the folding area of the Qiulitage tectonic belt led to the obstruction of the oil and gas transmission system in the western portion of the study area.As a result,Group Ⅰ oils were predominantly distributed in the eastern part of the study area.However,in the se

关 键 词：库车前陆盆地 油气聚集 油气成藏过程 族群划分 秋里塔格构造带 

分 类 号：P618.13[天文地球—矿床学] TE112[天文地球—地质学]