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西北地区侏罗纪煤系地层中主要的生烃显微组分是孢子体、角质体、藻类体、沥青质体、碎屑类脂体、基质镜质体等，而树脂体、木栓质体等早期低熟生油组分含量很低。从煤中分离出来的一些主要单显微组分的热解模拟显示它们成烃演化特征基本相似， 主要生油窗在模拟温度３６０ ～４５０ ℃， 生油高峰在３９０ ～４２０ ℃， 分别相应于 Ｒｏ 约０ ．７ ％ ～１ ．２ ％ 和０ ．９５ ％ ～１ ．０％ 左右。显微荧光分析表明，镜质组反射率Ｒｏ 在约０ ．７ ％ 左右时，次生荧光大量出现，并随成熟度增加而逐渐增加，标志着大量生油的开始。煤中可溶有机质含量从泥炭阶段至烟煤阶段逐渐降低，并未显示转化率高峰，但烃类转化率高峰在Ｒｏ ０ ．８ ％ ～１ ．２ ％ 阶段。可溶有机质组分的变化也充分表明， 煤系有机质主要生排油时期是在Ｒｏ ＞ ０ ．７ ％ 时的成熟阶段。西北地区侏罗纪煤系含油气盆地中目前发现的油气一般分布于成熟烃源岩分布区及邻近地区。因此，侏罗纪煤系有机质成油模式是热降解成熟生油模式。
The main hydrocarbon generation microscopic components in the Jurassic coal measures strata in Northwest China are sporophytes, keratoplasts, algae bodies, asphaltenes, clastic lipids, matrix vitrinites and the like, whereas resinous bodies, cork bodies and the like Early low-maturity oil content is low. The pyrolysis simulations of some major single micro-components isolated from coal show that the hydrocarbon generation evolutionary characteristics are basically similar. The main oil production window is at the temperature of 360-450 ℃ and the peak of oil generation is 390-420 ℃, corresponding to Ro is about 0. 7% ~ 1. 2% and 0. 95% ~ 1. 0% or so. Micro-fluorescence analysis showed that the vitrinite reflectance Ro was about 0. At around 7%, secondary fluorescence appeared in large numbers and gradually increased with maturity, marking the beginning of a large amount of oil production. The content of soluble organic matter in coal gradually decreased from peat stage to bituminous coal stage, but did not show the peak of conversion rate, but the peak of hydrocarbon conversion was at Ro 0. 8% ~ 1. 2% stage. The changes of soluble organic components also fully show that coal-based organic matter is mainly produced at Ro> 0. 7% when the maturity stage. Hydrocarbons currently found in the Jurassic coal measures petroliferous basins in the northwest are generally distributed in mature hydrocarbon source rock distribution areas and adjacent areas. Therefore, the Jurassic coal measures organic oil formation model is a thermal degradation of mature oil generation mode.