鄂尔多斯盆地林镇地区原油地球化学特征

林镇地区是鄂尔多斯盆地中生界油气勘探新区，近几年在该地区发现了延长组上部和延安组下部的复合油藏。通过对鄂尔多斯盆地林镇地区原油样品和区域内烃源岩样品进行系统采集和GC-MS分析，研究了原油和烃源岩中生物标志化合物的组成和分布特征，探讨了延安组延6、延8、延9和延长组长3等油层组原油的成因；油源对比研究表明该地区延安组与延长组原油的地球化学特征均与上三叠统延长组长7烃源岩具有亲缘关系，说明原油主要来源于长7烃源岩。这些研究成果为林镇地区石油勘探开发提供了科学依据。

Geochemical Characteristics of Crude Oil from Linzhen Area in the Ordos Basin,China

Linzhen area is a new Mesozoic petroleum exploration target in the Ordos Basin,China.A series of oil reservoirs of upper Triassic Yanchang Formation and lower Jurassic Yanan Formation have been found in this area recently.In this paper,crude oil samples from Linzhen area were collected systematically and analyzed by means of high-resolution GC-MS technique.The compositional and distributional characteristics of biomarker compounds in oils from Yan-6,8,9 subsections of Yan′an Formation and Chang-3 subsection of Yanchang Formation were studied and the origin of crude oils is discussed in detail.The biomarker features show that the oils were formed under a weakly reducing freshwater environment and are mature.The results of oil-source rock correlation show that the geochemical characteristics of Yanchang Formation and Yan′an Formation crude oils from Linzhen area are similar to those of the upper Triassic Chang-7 subsection,indicating that the crude oils originated mainly from the Chang-7 source rock.