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本文简要论述了民和盆地中侏罗统含煤及油页岩层系的生油特征，探讨了盆地独特的石油地质和地球化学条件。原油主要地化特征为：Ｐｒ／Ｐｈ比值偏高（２．６５—３．１５）、甾烷／藿烷比值极低（０．０３）、Ｃ２７甾烷较丰富、Ｔｓ／Ｔｍ＞１、低硫芴／氧芴比值、较高含量的Ｃ２９降新藿烷及重排藿烷类化合物及相对丰富的长链联苯及烷基四氢萘系列化合物。中侏罗统煤－泥页岩层系含生油潜力明显不同的多类型油页岩，多数油页岩属由藻类和陆生高等植物母质组成的混合型有机质，沉积环境为淡水－微咸水弱氧化条件，其地化特征也表现为高Ｐｒ／Ｐｈ比值（平均为１．９８），低甾烷／藿烷及低硫芴／氧芴比值等特征。某些油页岩富含Ｃ２９降新藿烷及重排藿烷系列化合物，它们应为主力源岩。油页岩多含再沉积型或沉积改造型有机质。异常地热作用对源岩演化及原油地化特征有重要影响
This paper briefly discusses the characteristics of oil generation in Middle Jurassic coal-bearing and oil shale formations in the Minhe Basin, and discusses the unique petroleum geology and geochemical conditions of the basin. The main geochemical characteristics of crude oil are: high Pr / Ph ratio (2.65-3.15), very low ratio of sterane / hopane (0.03), relatively rich C27 sterane, Ts / Tm> 1, low Sulfur fluorene / fluorene ratio, a higher content of C29 desublastin and rearranged hopane compounds and relatively rich long-chain biphenyl and alkyl tetralin series of compounds. Middle-Jurassic coal-shale formations contain multiple types of oil shale with distinctly different potential for oil generation. Most oil shale is a mixed organic matter consisting of algae and terrestrial plantago. The sedimentary environment is freshwater-brackish water Weak oxidation conditions, the geochemical characteristics also showed high Pr / Ph ratio (average of 1.98), low sterane / hopane and low sulfur fluorene / fluorene ratio and other characteristics. Some oil shale is rich in C29 desorbed hopane and rearranged hopane series of compounds, they should be the main source rock. The oil shale contains more redeposited or sediment-modified organic matter. Abnormal geothermal effects have an important influence on the evolution of source rocks and the geochemical characteristics of crude oil