论文部分内容阅读
贵州务川—正安—道真(务—正—道)铝土矿属于古风化壳沉积型铝土矿床,是黔中—渝南铝土矿成矿带的重要组成部分。铝土矿产于中下志留系韩家店组(S1-2hj)泥页岩或上石炭统黄龙组(C2h)灰岩的侵蚀面上,含矿层位为中二叠统梁山组(P2l)。根据元素地球化学特征及相关分析表明,Ti、Zr、Nb、Cr、Th、Ga、Hf、Ta及V在铝土矿矿化过程中均为不活动元素。特别是Ti在铝土矿矿化过程中性质最稳定,故可对其用于质量平衡的计算。铝土矿化过程中一些元素的质量变化可以通过不活动元素在铝土矿(岩)和中下志留系韩家店组(S1-2hj)泥页岩中的含量变化来估算。计算结果显示,大多数活动元素从铝土矿体系中移走,部分Si、Mg、K、Fe以及少量的弱活动性Al向下渗透,并沉淀为伊利石(绢云母、绿泥石)、赤铁矿和石英或非晶体硅。通过系统研究和质量平衡计算,可初步确定S1-2hj泥页岩为务—正—道铝土矿主要的成矿原岩。
Guizhou Wuchuan - Zheng’an - Daozhen (service - is - Road) bauxite belongs to the ancient weathered crust bauxite deposits, is an important part of the Central Guizhou - Chongqing South bauxite ore belt. Bauxite is produced on the erosion surface of the Middle-Lower Silurian Hanjiandian (S1-2hj) shale or Upper Carboniferous Huanglong Formation (C2h) limestone and the ore-bearing layer is the Middle Permian Liangshan Formation (P2l ). Based on the element geochemical characteristics and correlation analysis, it is shown that Ti, Zr, Nb, Cr, Th, Ga, Hf, Ta and V are all inactive elements during the mineralization of bauxite. In particular, Ti is most stable in the mineralization of bauxite, so it can be used to calculate the mass balance. The mass change of some elements in the process of bauxite mineralization can be estimated by the change of the content of the inactive elements in shale in the bauxite (rock) and the Lower Silurian Hanjiandian Formation (S1-2hj). The results show that most of the active elements are removed from the bauxite system, part of Si, Mg, K, Fe and a small amount of weakly active Al penetrate downwards and precipitate as illite (sericite, chlorite) Hematite and quartz or amorphous silicon. Through systematic research and mass balance calculation, S1-2hj shale can be initially identified as the main ore-forming protolith in the service-normal-channel bauxite.