南羌塘坳陷中侏罗统布曲组油藏带流体包裹体特征与油气充注历史  

Fluid inclusions characteristics and hydrocarbon charging history of oil reservoir belt in the Mid-Jurassic Buqu Formation,Southern Qiangtang depression

作　　者：夏国清[1,2] 季长军[3] 杨伟[1,4] 吴驰华[5] 伊海生[1,2] 张帅[1] 李启来 李高杰[1] 

机构地区：[1]成都理工大学沉积地质研究院,四川成都610059 [2]油气藏地质及开发工程国家重点实验室,四川成都610059 [3]中国地质科学院,北京100037 [4]四川省核工业地质局二八二大队,四川德阳618000 [5]中国地质科学院矿产资源研究所国土资源部成矿作用与资源评价重点实验室,北京100037

出　　处：《石油学报》2016年第10期1247-1255,共9页Acta Petrolei Sinica

基　　金：国家自然科学基金项目(No.41402099);成都理工大学油气藏地质及开发工程国家重点实验室开放基金项目(No.PLC201603);国土资源部沉积盆地与油气资源重点实验室开放基金项目(No.zdsys2014002)资助

摘　　要：南羌塘坳陷中侏罗统布曲组含油白云岩中发育有大量与烃类活动有关的流体包裹体,其记录了油藏带油气运移、聚集和成藏过程。在流体包裹体岩相学研究的基础上,开展了包裹体显微荧光分析和均一温度测试,并划分了油藏带原油类型,讨论了油气充注过程。结果表明:1油藏带表现出多幕次油气聚集成藏特征,存在4类不同成熟度的原油包裹体和1类干气包裹体充注,尽管4类原油包裹体在隆鄂尼区块和昂达尔错区块的显微荧光颜色存在差异,但光谱波峰形态相似,而主峰波长和红绿熵参数则明显不同,推测其来自同一烃源岩的不同成熟度阶段。2油藏带主成藏期在晚侏罗世—早白垩世期间,是盆地经历最大埋深阶段油气充注时期;但在早白垩世时期,局部的构造活动导致原生油藏发生二次调整,油包裹体呈非均一相,平均均一温度和盐度均发生变化;新近纪中晚期(盆地第二次生烃高峰时期),差异性沉陷或局部的热异常致使部分油气转化成干气,并伴随流体运移、捕获、充注于白云石颗粒和方解石胶结物中。Large number of fluid inclusions related to hydrocarbon activities are discovered in the oil-bearing dolomites of the Mid-Jurassic Buqu Formation,Southern Qiangtang depression,recording the hydrocarbon migration and accumulation process of oil reservoir belt.In this paper,microscopic fluorescent analysis and homogenization temperature test are conducted based on the petrography of fluid inclusions,to distinguish the crude oil types in oil reservoir belt and explore the hydrocarbon charging process.The obtained results indicate that：1）the oil reservoir belt have characteristics of multi-episode hydrocarbon migration and accumulation,with four types of crude oil inclusions with different maturities and one type of dry-gas inclusion charging.Although the differences exist in the microscopic fluorescent colors of four types of crude oil inclusions in the Long＇eni block and Angdaercuo block,the similarities of spectral peak shapes and distinct differences of the main peak wavelengths and red-green entropy parameters between them suggest that these crude oil inclusions may be formed in different maturity stages of the same source rocks.2）the main accumulation period of the oil reservoir belt is from Late Jurassic to Early Cretaceous and is attributed to hydrocarbon charging in the basin with maximum buried depth.During the Early Cretaceous period,the adjustment of primary oil reservoirs caused by local tectonic activities,resulted in the non-uniform phase of oil inclusions,with,large anomalies in mean homogenization temperature and salinity.During the mid-late Neogene period（the peak period of the second hydrocarbon generation in the basin）,part of oil and gas was transferred to dry gas due to the differential subsidence and local thermal anomaly,and finally charged into dolomite particles and calcite cements with migration and capture of fluid.

关 键 词：流体包裹体 油气充注期次和时期 布曲组 油藏带 南羌塘坳陷 

分 类 号：TE122.1[石油与天然气工程—油气勘探]