鄂尔多斯盆地西缘南段上古生界烃源岩综合评价

Comprehensive Evaluation of Upper Paleozoic Source Rocks in the Southern Section of the Western Edge of Ordos Basin

正确认识研究区烃源岩的分布层位和发育规模,生烃潜力,全面搞清楚研究区的资源结构,将为研究区进行油气勘探提供重要依据,对今后的区带评价和目标选择具有十分重要的意义。通过利用鄂尔多斯西缘南段上古生界煤系泥岩、煤岩的有机地化分析测试资料,并且结合前人研究成果,系统地对研究区古生界烃源岩地质、地球化学特征进行了研究。研究结果表明:按煤系泥岩型烃源岩有机碳丰度标准,太原组、山西组泥岩型烃源岩整体属中等级别烃源岩;按煤岩型烃源岩有机质丰度标准,太原组、山西组煤岩属极好类型烃源岩。太原组、山西组烃源岩的有机质类型以Ⅲ型干酪根为主,均处于高成熟生气阶段。

Correct understanding of source rock distribution horizon and development scale, hydrocarbon potential, the resource structure of the study area, is an important basis for oil and gas exploration in the study area, and has very important significance for district target evaluation and selection in the future. In this paper, based on organic geochemical analysis test data of Upper Paleozoic coal-bearing mudstones and coal rocks in the southern section of in the western edge of Ordos Basin, combined with previous studies, geological and geochemical characteristics of Palaeozoic source rocks in the study area were studied. The results show that, according to coaly mudstone source rocks organic carbon abundance standards, mudstone type source rocks in Taiyuan Formation and Shanxi Formation belong to middle-level source rocks; According to coal-rock source rocks organic carbon abundance standards, coal rocks in Taiyuan Formation and Shanxi Formation belong to very good source rocks. The type of organic matter of source rocks of Taiyuan Formation and Shanxi Formation is mainly type III Kerogen, and all of the source rocks are in the stage of high maturity.