鄂尔多斯盆地三叠系延长组油藏成藏年代分析

鄂尔多斯盆地中生界油藏的成藏研究近来日益受到重视,并开始取得了一些重要进展。但有关该区中生界油藏的成藏年代学研究以往则开展很少。笔者主要运用有机包裹体分析方法、结合生烃史分析,对该盆地具有代表性的陕北斜坡三叠系长6油藏与长2油藏的成藏年代进行了探讨。分析表明,陕北斜坡三叠系长6与长2油藏的有机包裹体特征十分相似,其共生盐水包裹体的均一温度也十分相近,基本上均在110～120℃,说明二者在成藏时间上十分接近。根据埋藏史和热演化史分析结果,陕北斜坡三叠系延长组长6与长2油藏的成藏时间大体在早白垩世晚期。

Geochronological Analysis of Oil Accumulation in Triassic Yanchang Formation, Ordos Basin

In recenty ears,more and more attention is paid on hydrocarbon accumulation research of Triassic Yanchang formation in Ordos basin and important progress has been made.Nevertheless, geochronology of Mesozoic reservoirs in this area was rarely studied in the past years.Geochronology of the Triassic Chang 2 and Chang 6 oil-bearing Formation in eastern North Shaanxi slope which is studied through organic inclusion analysis method with analysis of hydrocarbon generating history in this paper. The study shows that or ganic inclusion characteristics of the Triassic Chang 2 and Chang 6 oil-bearing Formation in eastern North Shaanxi Slope are very similar.The homogeneous temperature of the inclusions is 90-120℃.It shows that the forming times of hydrocarbon accumulation of the Triassic Chang 2 and Chang 6 oil-bearing Formation in eastern North shaanxi slope are very close.On the basis of analysis of burial history and thermal evolution history,the age of accumulation is nearly the late Early Cretaceous.