琼东南盆地宝岛凹陷南北断阶带古近系陵水组三段天然气差异富集机理  

Comparative Analysis of Gas Enrichment Differences in the Third Member of the Paleogene Lingshui Formation in the South-North Step-Fault Zone of Baodao Sag, Qiongdongnan Basin

作　　者：袁朱晔斐 田杨 熊小峰 叶琳 左高昆 吴楠[1] 朱晋杰 Yuan Zhuyefei;Tian Yang;Xiong Xiaofeng;Ye Lin;Zuo Gaokun;Wu Nan;Zhu Jinjie(School of Geosciences,Yangtze University,Wuhan 430100,China;CNOOC China Limited,Hainan Branch,Haikou 570312,China;School of Earth Resources,China University of Geosciences(Wuhan),Wuhan 430074,China)

机构地区：[1]长江大学地球科学学院,武汉430100 [2]中海石油(中国)有限公司海南分公司,海口570312 [3]中国地质大学(武汉)资源学院,武汉430074

出　　处：《吉林大学学报（地球科学版）》2024年第6期1998-2013,共16页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(42172179);湖北省教育厅科学研究计划资助项目(Q20221311)。

摘　　要：琼东南盆地宝岛凹陷沉积-构造演化复杂,存在多套生储盖组合。南北断阶带是宝岛凹陷现今主要油气富集区,古近系陵水组三段优质的三角洲砂体是其主要目的层。本文综合测井、地震、地球化学等资料,开展陵水组三段天然气富集静态要素对比研究,并结合盆地模拟技术,阐明天然气动态成藏的差异性,总结其主要控制因素。研究表明:北部断阶带甲烷体积分数偏低,非烃类气体体积分数高,以干气为主;南部断阶带天然气组分中烃类气体体积分数高,具有干气与湿气混合特征。北部断阶带为中孔、低渗储层,输导模式主要为T字型+Z字型混合输导;南部断阶带为中孔、低渗—特低渗储层,输导模式以Z字型输导为主。北部断阶带BD21-1区块圈闭定型于三亚组末期,圈闭构造高点转为东西向,控凹断层活动,控圈断层持续变形,早期崖城组内生成的油气通过次级断层进入储层,后期控凹断层停止活动,通过控圈断层垂向运移至陵水组砂体。南部断阶带YL10-6区块北部圈闭定型于三亚组末期,后期受挤压应力影响,于F_(10-1)断裂处形成小背斜圈闭,其早期与晚期输导体系类型均为Z字型。南北断阶带陵水组三段均经历了3期油气充注,天然气差异富集机理为各生烃次洼生烃潜力、油气初次运移富集程度和二次运移保存条件的差异。The sedimentary-tectonic evolution of Baodao sag in the Qiongdongnan basin is complex,with many sets of source-reservoir-seal assemblages in Baodao sag,Qiongdongnan basin.The south-north step-fault zone is the main oil and gas enrichment area in Baodao sag,the high-quality deltaic sand bodies in the Third Member of the Lingshui Formation of Paleogene are the main target beds.Based on the data of logging,seismic and geochemical data,this paper makes a comparative study on the static factors of gas enrichment in the Third Member of Lingshui Formation,and expounds the difference of gas dynamic accumulation by combining with basin simulation technology,the main control factors were summarized.The results show that the methane content is low and the non-hydrocarbon gas content is high in the northern step-fault zone,and the dry gas is the main gas in the southern step-fault zone.In the northern part of the step-fault zone,the medium porosity and low permeability reservoirs are mainly transported by T type and Z type mixed reservoirs,while in the southern part of the step-fault zone,the medium porosity,low permeability and ultra-low permeability reservoirs are mainly transported by Z type reservoirs.The trap of block BD211 in the northern fault step zone was formed at the end of the Sanya Formation,and the structural high point of the trap turned to the east-west direction,in the early stage,the oil and gas generated in Yacheng Formation entered the reservoir through secondary faults.The trap in the northern part of block YL106 in the southern fault step was characterized as a small anticline trap at the F 101 fault zone,which was formed at the end of the Sanya Formation and was influenced by compressive stress at the late stage.The Third Member of Lingshui Formation in the south-north step-fault zone experienced three stages of oil and gas charging.The gas differential enrichment depends on the differences in hydrocarbon potential of sub-depression,enrichment degree during primary migration,and preservation situation

关 键 词：差异富集机理 成藏期次 天然气 储层 宝岛凹陷 南北断阶带 陵水组三段 琼东南盆地 

分 类 号：TE12[石油与天然气工程—油气勘探] P618.13[天文地球—矿床学]