永利探区上古生界烃源岩特征

Characteristics of Upper Palaeozoic source rock in Yongli exploration area

永利探区是鄂尔多斯盆地西缘逆冲断裂带中部上古生界含气区。通过对上古生界烃源岩的有机质丰度、有机质类型和源岩有机质成熟度进行研究,明确了太原组是上古生界成藏的有效气源岩层,主要地化指标从山西组到太原组具有变好的趋势,太原组优于山西组。演化程度处于成熟阶段,且随着深度的增加有机质丰度由低变高。

Yongli exploration area is a gaseous section of Upper Palaeozoic in the middle of thrust fauhed belt in the western edge of Ordos Basin. Through the study of organic matter abundance, organic matter types and organic matter maturity of Upper Palaeozoic source rocks, it is proved that the Taiyuan Formation is the effective gas source rocks of gas accumulation in Upper Palaeozoic. Primary geochemical index has a good changing trend from Shanxi Formation to Taiyuan Formation. Taiyuan Formation, which is superior to Shanxi Formation, is in mature phase during its evolution. The organic matter abundance is from low to high along with the depth increasing.