贵州织金县以那地区龙潭组煤质特征及其沉积环境指示

成煤环境与煤质特征关系紧密，泥炭沼泽期陆源输入强度、海水进退以及氧化还原条件对煤中元素分布和组成具有重要影响。本次研究利用贵州织金县以那地区三个煤矿勘查区共46口钻孔主采煤层的煤质分析结果，分析了龙潭组自下而上煤质参数分布特征，并在此基础上探讨了硫分和灰成分指数对成煤环境的指示作用。研究结果表明：(1)以那地区无烟煤全硫分含量较低，平均为2.19%，以无机硫为主，煤灰分中主量元素以SiO₂为主，Al₂O₃和Fe₂O₃次之，其他含量较低；(2)各煤层全硫含量、有机/无机硫在全硫中占比、主量元素组合(Fe₂O₃+CaO+MgO和SiO₂+Al₂O₃)含量呈现相互匹配的变化规律，煤灰成分指数变化规律不明显；(3)以那地区龙潭组自下而上经历了三期海水进退过程，发育潮坪下三角洲平原、三角洲分流间湾和潮坪-瀉湖三种成煤环境，硫分与灰成分指数在成煤环境指示作用上具有较好的一致性。

Coal quality characteristics and sedimentary environment indication of the Longtan Formation in the Yina area of Zhijin County, Guizhou Province

Coal-forming environment is closely related to the characteristics of coal quality. The intensity of terrestrial input during peat swamp period, marine transgression and regression, and the redox conditions have important effects on the distribution and composition of elements in coal. This study utilized the coal quality analysis results of 46 main coal seams drilled from three coal mine exploration areas in the Yina area of Zhijin County, Guizhou Province to analyze the distribution characteristics of coal quality parameters in the Longtan Formation from bottom to top. Based on this, the indication role of sulfur content and ash composition index on the coal-forming environment was explored. The results show that: (1) The total sulfur content of anthracite in the Yina area is low, with an average value of 2.19%, and the inorganic sulfur is the main element. The main element in the ash is SiO2, followed by Al2O3 and Fe2O3, and other contents are low; (2) The total sulfur content of each coal seam, the proportion of organic/inorganic sulfur in total sulfur, and the content of major element combinations (Fe2O3+CaO+MgO and SiO2+Al2O3) show a mutually matched change pattern, while the change pattern of coal ash composition index is not obvious; (3) The Longtan Formation in the Yina area has undergone three stages of marine transgression and regression from bottom to top, developing three types of coal-forming environments: tidal flat delta plain, delta distributary bay, and tidal flat lagoon. The sulfur and ash composition indices have good consistency in indicating the coal-forming environment.