鄂尔多斯盆地陇东地区延长组含油气流体活动期次与石油充注史

利用显微荧光与包裹体显微测温技术，并结合烃源岩生排烃史分析，探讨了鄂尔多斯盆地陇东地区延长组含油气流体活动期次及石油充注历史。结果表明：陇东地区延长组烃源岩开始排烃的时期为早白垩世早期（约133 Ma），主要存在两期含油气流体活动，第一期含油气流体活动发生在早白垩世主力源岩排烃期间（133~100 Ma），第二期含油气流体活动发生在晚白垩世构造抬升期间（100~70 Ma）。早白垩世期间石油的充注表现为充注强弱程度不同的连续过程，晚白垩世以来生烃停止导致石油的充注与运移逐渐减弱并在晚白垩世末期基本停止。

Hydrocarbon Fluid Flow Stages and Oil Migration History in Yanchang Formation of Longdong Area, Ordos Basin

In combination with analysis of hydrocarbon generation and expulsion history,hydrocarbon fluid flow stages and oil migration history in Yanchang Formation of Longdong area in Ordos Basin are studied by analyzing fluid inclusions through microfluorometric and microscopic thermometry technology.The results reveal that the time of oil expulsion from source rocks is the early stage of Early Cretaceous.Two hydrocarbon fluid flow stages have occurred in Yanchang Formation.The first stage of hydrocarbon fluid flow happened in the Early Cretaceous(from 133 to 100 Ma) during hydrocarbon generation and expulsion of main source rocks,and the second stage of hydrocarbon fluid flow happened in the Late Cretaceous(from 100 to 70 Ma) during the tectonic uplift.Oil migration in the Early Cretaceous showed a continuous process with different oil migration strength,but it weakened gradually as a result of the cease of oil generation caused by the tectonic uplift during the Late Cretaceous and ultimately ended in the late stage of the Late Cretaceous.