This paper discusses the volcanic influence on the mineralogical and elemental geochemistry of No. 6 coal from Nanyangpo Mine in the Datong coalfield, north China. Sixteen samples (14 coal and 2 partings) were analyzed by different geochemical methods. The results revealed that the No. 6 coal is a medium–high volatility, highly calorific, bituminous coal with a low-ash and medium-sulfur content. The minerals mainly consisted of kaolinite, calcite, dolomite, and pyrite. In addition, traces of apatite, sphalerite, and anatase were also found. Calcite, dolomite, and pyrite in the coal samples were mainly derived from epigenetic hydrothermal solutions, whereas kaolinite and apatite originated from volcanic ash. Harmful trace elements including Pb, Cu, Mo, Tl, and Hg in the No. 6 coal samples were higher than those of common global coals. These harmful elements mainly occurred in sulfide minerals, which were probably influenced by hydrothermal inputs.

中文翻译：

---

华北大同煤田南洋坡矿6号煤地球化学特征：重视热液影响

本文讨论了火山对华北大同煤田南洋坡矿6号煤矿物学和元素地球化学的影响。通过不同的地球化学方法分析了 16 个样品（14 个煤和 2 个分离物）。结果表明，6号煤为中高挥发性、高发热量、低灰分、中硫的烟煤。矿物主要有高岭石、方解石、白云石和黄铁矿。此外，还发现了磷灰石、闪锌矿和锐钛矿的痕迹。煤样中方解石、白云石和黄铁矿主要来源于后生热液，高岭石和磷灰石主要来源于火山灰。6号煤样中有害微量元素Pb、Cu、Mo、Tl、Hg均高于全球常见煤样。