鄂尔多斯盆地中西部延长组下组合油源对比

Oil-source rock correlation in the Lower Yanchang Formation of the middle-western Ordos Basin

通过对鄂尔多斯盆地中西部地区延长组长7,长9及长10段烃源岩样品和长8,长9及长10油层组原油样品的正构烷烃及甾烷生物标志化合物特征的对比研究,厘定油源关系,揭示鄂尔多斯盆地中西部地区延长组下组合石油的来源。研究结果表明,不同区域不同层位烃源岩和原油的正构烷烃及甾烷生物标志化合物特征具有差异性,长8原油在研究区西部来源于长7烃源岩,在东部及南部来源于长7和长9烃源岩;长9原油在西部来源于长10烃源岩,在东部及南部来源于长9和长10烃源岩;长10原油在南部来源于长10和长9烃源岩。

To reveal the origin of crude oil in the Lower Yanchang Formation in the middle-western Ordos Basin. According to the comparison of biomarker features of n-alkanes and steranes in source rocks of Chang 7, Chang 9 and Chang 10 and crude oil of Chang 8, Chang 9 and Chang 10 in the middle-western Ordos Basin, in this paper oil-source correlation is revealed. Biomarker features of n-alkanes and steranes in source rocks and crude oil are different in the Lower Yanchang Formation of different areas. Crude oil of within Chang Chang 8 originated from the source rocks 7 in the western area, and it came from the source rocks within Chang 7 and Chang 9 in the eastern and southern area; crude oil of Chang 9 originated from the source rocks within Chang 10 in the western area, and it came from the source rocks within Chang 9 and Chang 10 in the eastern and southern area; crude oil of Chang 10 originated from the source rocks within Chang 10 and Chang 9 in the southern area.