黔西南高砷煤的分布及地球化学特征研究

Distribution of high arsenic coals from Southwest Guizhou Province

根据野外地质特征结合中子活化成分分析结果，探讨了黔西南高砷煤的分布特征、影响因素和某些地球化学特征。高砷煤严格受构造（褶皱和断层）、地层（二叠系龙潭组）、沉积相（海陆交互相）的控制，分布于平行背斜长轴的断层两侧，愈靠近断层面砷的含量愈高。砷在煤中的分布极不均匀，即使同一煤层变化也极大。在时空关系与元素组合上高砷煤与区内卡林型金矿密切相关。

Based on field geology and chemical analysis, the distribution, controlling factors and some geochemical characters of high arsenic coals in southwestern Guizhou Province are discussed in this paper. Geological structures, such as anticlines and faults and sedimentary stratum, control the distribution of high arsenic coals. High arsenic coals distribute in the two sides of striking faults that are parallel to the anticlinal axes. The closer to the fault plane the coal is, the higher the arsenic content of coal. The arsenic content of coal changes greatly in different coal beds and in different locations of the same bed, even if in the same seam. High arsenic coals belong to Longtan facies that is alternation of marine and terrestrial facies. Trace elements analysis results show that the sedimentary environment of high arsenic coals is mainly terrestrial origin with some interchange of marine characteristics. Small gold, arsenic, antimony and mercury, deposits/mineralizations are found near high arsenic coals, showing that high arsenic coals may be associated with the Carlin- type gold deposits in the study area.