Abstract This paper reports on the petrological and geochemical compositions of K9 and K4 coals in the Late Permian Longtan Formation in the Gemudi Mine, which is located in the western Guizhou, southwest (SW) China. Critical metal concentrations have not been reported and there is a significant difference in the V concentration between the lower part and the upper part in the K9 coal of Gemudi Mine. Thus, it is a good research object of the enrichment mechanism of V. The studied coals are medium volatile bituminous coals that are characterized by a medium–high ash yield (21.7% and 37.7% on average, respectively) and a low sulfur content (0.81% and 0.18% on average, respectively). Vitrinite is the major maceral group in both coals, and collotelinite and collodetrinite contribute the most to it. Clay minerals (mainly kaolinite, illite, and illite/smectite mixed) are the majority of the minerals, quartz, carbonite minerals and pyrite are also found in the coal samples. Correspondingly, SiO2 and Al2O3 are the major components in ash, and both of them are highly correlated with the ash yield. Vanadium (213μg/g on average) is the single enriched element in K9 coal, and it is also enriched in K4 coal. Vanadium is significantly enriched in the lower part of K9 coal, but it is depleted in the upper portion. A correlation analysis indicated that V in K9 coal mainly has an organic association, and it is positively related to telinite. Whereas, the cell and crack filling chlorite is likely to be the predominant occurrence mineral of V. Terrigenous detritus from the Emeishan basalt in the Kangdian Upland represents main origin of V in Gemudi coals, and hydrothermal fluids reformed some part of V in the K9 coal. The reducing depositional environment provides the preservation conditions as well.

中文翻译：

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黔西地区格木地矿晚二叠世煤中钒的富集

摘要 本文报道了贵州西部贵州西部地区晚二叠世龙潭组K9和K4煤的岩石学和地球化学组成。格木地矿K9煤中，临界金属浓度未见报道，下部与上部V浓度存在显着差异。因此，它是V的富集机制的一个很好的研究对象。 研究的煤是中挥发性烟煤，其特征是中高灰分（平均分别为21.7%和37.7%）和低硫含量（平均分别为 0.81% 和 0.18%）。镜质体是两种煤中的主要微晶组，其中胶凝体和胶凝体对它的贡献最大。粘土矿物（主要是高岭石、伊利石、和伊利石/蒙脱石混合）是大部分矿物，石英、碳酸盐矿物和黄铁矿也在煤样品中发现。相应地，SiO2 和 Al2O3 是灰分中的主要成分，两者都与灰分产量高度相关。钒（平均213μg/g）是K9煤中单一的富集元素，K4煤中也富集。K9煤下部钒明显富集，上部贫钒。相关性分析表明，K9煤中的V主要是有机缔合，与铁质岩呈正相关。而细胞和裂缝填充绿泥石很可能是 V 的主要赋存矿物。 康店高地峨眉山玄武岩陆源碎屑是格姆地煤 V 的主要成因，和热液流体重整了 K9 煤中的部分 V。还原沉积环境也提供了保存条件。