中文摘要：

鄂尔多斯盆地上三叠统瓦窑堡煤系是我国重要的含煤岩系，主要发育有5号煤层和3号煤层．生烃母质研究表明，瓦窑堡煤系的主要显微组分为镜质组，其中富氢基质镜质体含量高，一般大于40％，含有〉10％的壳质组显微组分，且以孢子体为主，碳质泥岩中藻类体常见。有机地球化学研究表明，煤的平均有机碳含量达70wt．％，镜质体反射率为0．6％～0．8%，氢指数平均达250mgHC／g·TOC，族组分组成表现出煤成油的族组分特征，结合生物标志物特征，反映有机质类型属于Ⅱ型，处于低成熟一成熟演化阶段。据此可以认为，瓦窑堡煤系具有良好的生烃潜力，并且5号煤要优于3号煤，这将有助于认识这套煤系及其油气地质意义．

英文摘要：

The Wayaobu formation of Upper Triassic in Ordos Basin is one of the most important coal measures in northern China. It contains over twenty coal beds, among which the No. 3, No. 5 coal beds are extensively distributed and are major workable coal seams. In this paper, bio precursor and organic geochemical features of the Wayaobu coal measure were studied. The results showed that vitrinite was the main maceral of the Wayaobu coal measure, which contained up to 40 % desmocollinite, and above 10 % liptinite that consists of mainly sporinite in the coal measure. Algainite was often observed in carbargilites. The average value of organic carbon is up to 70 wt. % ; the vitrinite reflectance is 0.6-0.8% ; the average hydrogen index is larger than 250 mgHC/g · TOC. Organic geochemistry indicated that the organic matters of the Wayaobu coals were of Ⅱ type and low-middle maturity. This paper suggested that Wayaohu coal measure has high oil production. Furthermore, the No. 5 coal seam has higher oil-generating ability than the No. 3. These results will be helpful for understanding the oil/gas geological significance of this coal measure.