鄂尔多斯盆地中部三叠系延长组下组合有机流体活动与关键成藏期次  

Organic fluid activity and key accumulation period of the Triassic Lower Yanchang Formation,central Ordos Basin

作　　者：王建华[1] 葛云锦 杜克锋 李红进 Wang Jianhua;Ge Yunjin;Du Kefeng;Li Hongjin(Yanchang Oilfield Co.,Ltd.,Yan'an 716000,China;Research Institute of Shaanxi Yanchang Petroleum(Group)Co.,Ltd.,Xi'an 710075,China)

机构地区：[1]延长油田股份有限公司,陕西延安716000 [2]陕西延长石油(集团)有限责任公司研究院,陕西西安710075

出　　处：《能源与环保》2020年第5期55-60,共6页CHINA ENERGY AND ENVIRONMENTAL PROTECTION

基　　金：国家科技重大专项资助项目(2011ZX05003-001)。

摘　　要：以显微观察、荧光光谱、包裹体测试等为手段,对鄂尔多斯盆地中部三叠系延长组下组合有机流体活动与关键成藏期次进行了精细研究。结果表明,下组合储层中存在3期油气充注,其中碳质沥青时间最早,黄白色荧光有机流体次之,蓝白色荧光有机流体充注时间最晚。包裹体均一温度结合埋藏史表明,3期成藏时间分别为侏罗纪中晚期、侏罗纪末期—早白垩世早期、早白垩世晚期。有晚期蓝—蓝白色荧光有机物的区域一般有早期碳质沥青或黄白色荧光有机物发育,而有早期碳质沥青或黄白色荧光有机物的区域不一定有晚期蓝—蓝白色荧光有机物发育,表明晚期蓝—蓝白色荧光有机物的充注与早期原油充注具有密切的关系。原因是早期原油充注改变了储层润湿性,形成特低渗储层中的优势运移通道,晚期原油优先沿着优势通道运移。侏罗纪末期—早白垩世早期是研究区下组合油气成藏的关键时期。Based on the Microscopic observation,fluorescence spectrum,fluid inclusion,the authors discussed the organic fluid activity and key accumulation period of the Lower Yanchang Formation in central Ordos Basin.The results showed that there are three phases of charged oil in the Lower Yanchang Formation.The carbonaceous bitumen is the earliest Organic fluid activity,followed by the yellow-white fluorescent organic fluid,and the blue-white fluorescent organic fluid is the latest.The 3 periods of reservoir accumulation are the middle-late Jurassic,the late stage of Jurassic-early stage of Early Cretaceous,and late stage of Early Cretaceous.Areas with late blue-blue-white fluorescent organics generally have early carbonaceous pitch or yellow fluorescent organics.And areas with early carbonaceous bitumen or yellow fluorescent organic matter may not necessarily have late blue-blue-white fluorescent organic matter.It was shown that the filling of late blue-blue-white fluorescent organic matter is closely related to the filling of early oil.The reason is that the early oil filling changed the reservoir wettability and formed the dominant migration channel in the ultra-low permeability reservoir.Late oil migration occurs preferentially along the dominant channel.End of Jurassic and early stage of Early Cretaceous are the critical stage for the hydrocarbon accumulation of the Lower Yanchang Formation in the study area.

关 键 词：鄂尔多斯盆地中部 延长组下组合 油气成藏 关键时期 均一温度 

分 类 号：TE122.1[石油与天然气工程—油气勘探]