柴北缘大煤沟地区侏罗系记录了西北地区古环境演化的重要信息。文章通过对大煤沟剖面进行有机地球化学分析，尝试恢复大煤沟地区侏罗系的环境演化。分析认为，H/C比与C/N比、δ ¹³Ｃ呈现良好的负相关性。早侏罗世：C/N比和δ ¹³Ｃ整体逐渐减小，H/C比逐渐变大；中侏罗世：C/N比和δ ¹³Ｃ在前期保持稳定，后期急剧负偏，而H/C比则反之；晚侏罗世：C/N比和δ ¹³Ｃ基本保持低值不变，H/C比稳定在高值区间。早—中侏罗世有机元素C/N比多大于15，表明有机质来源主要以
陆生高等植物为主。大煤沟剖面古气候表现为两个旋回，在早侏罗世小煤沟组时期古气候特征为温湿—干热，自中侏罗世晚期古气候开始从温湿向干热演化。

The Jurassic strata in the Dameigou area of the North Qaidam Basin recorded the evolution of paleoenvironment in the Northwest. In this paper, the organic geochemical analysis of the Dameigou section is performed to reconstruct the environmental evolution of the Jurassic in the Dameigou area. The analysis reveals that the H/C ratio shows a good negative correlation with the C/N ratio and δ ¹³C. The C/N ratios and δ ¹³C values decrease gradually and the H/C ratio gradually increases during the Early Jurassic. In the Middle Jurassic, the C/N ratio and δ ¹³C remained stable in the early stage and the latter was sharply negative, while the H/C ratio was reversed. During the Late Jurassic, the C/N ratio and δ ¹³C remained largely unchanged and the H/C ratio was stable in the high value range. The C/N ratio of organic elements in the early-middle Jurassic is greater than 15, indicating that organic matter is mainly from terrestrial higher plants. The paleoclimate of the Dameigou section is characterized by two cycles: in the Early Jurassic Xiaomeigou Formation, the paleoclimate was  haracterized by warm-humidity-dry heat and the paleoclimate evolved from warm wet to dry hot in the late Middle Jurassic.