为研究华北板块西南缘中侏罗世煤层地球化学特征及其沉积环境，以义马盆地中侏罗世义马组2-3号煤层为研究对象，借助X射线荧光光谱仪、等离子体质谱仪等手段，运用地球化学理论和方法，详细研究了煤中地球化学特征及其所反映的沉积环境。研究结果表明：研究区常量元素含量与中国煤相比，SiO₂、P₂O₅和K₂O显著偏高，而Al₂O₃含量较低；微量元素中Cs富集，Sb、Nb、Ta、Zr、Hf亏损；稀土元素整体为轻微富集，δEu负异常，而δCe正异常，表明采样煤层未受岩浆、热液、海水影响，物源主要是陆源碎屑；Th/U、V/ (V+Ni）、Ce异常、Sr/Cu及气候指数分析表明，采样煤层古泥炭堆积于还原环境，成煤期整体处于半干旱气候。

In order to study the geochemical characteristics and sedimentary environment of the Middle Jurassic coal seam in the southwestern margin of the North China Plate, taking the coal of Yima Formation in Yima basin as the research object to study the geochemical characteristics and sedimentary environment of Middle Jurassic coal seams in the southwest margin of the North China plate, based on the data from X-ray fluorescence spectrometer and plasma mass spectrometer. The results show that: The content of major element of SiO₂, P₂O₅ and K₂O are significantly higher, while the content of Al₂O₃ is lower compared with Chinese coals. Enrichment of Cs and deficit of Sb, Nb, Ta, Zr and Hf in trace elements. The rare earth elements are slightly enriched as a whole, with negative Eu anomalies and positive Ce anomalies, indicating that the coal seam was not affected by magma, hydrothermal and seawater, and the provenance is mainly terrigenous clastic. It shows that the coal forming environment in reductive environment, and the whole coal forming period is in semi-arid climate environment by the analysis of Th/U, V/ (V+Ni), Ce anomaly, Sr/Cu and climate index.