黔东南铝土矿赋存于下二叠统梁山组,其含矿岩系具有沉积型铝土矿典型的“煤-铝-铁结构”,即下部发育铝质页岩夹菱铁矿结核,中部由含铝岩组夹多层豆状或土状铝土矿组成,上部由碳质页岩、砂岩夹煤层组成.沉积环境为海陆交互相-滨海边缘沼泽相,具有稳定的构造背景.通过含矿岩系物质组成结构分析和元素地球化学研究认为:“煤-铝-铁结构”在铝土矿中的普遍出现,是沉积型铝土矿在矿化过程中物理化学环境多变导致的深度去硅去铁作用,加之外部环境提供充足的有机质物质来源,从而形成的非偶然结果.因此,含矿岩系的分层结构形成过程中的物理化学变化所导致的多种地质异常可作为找矿实践中的成矿标志.%The bauxite in southeast Guizhou is hosted within the Lower Permian series Liangshan Group. The ore-bearing rock series shows a typical coal-bauxite-iron structure of the sedimentary type bauxite deposit, i. e. the aluminum shale intercalated within siderite tuberculosis developed at the bottom, aluminiferous rock association intercalated within multiple-layer pisolitic or earthy bauxite in the middle, and carbonaceous shale and sandstone intercalated with coal seams from the lower to the upper in the profile of bauxite. Presumably, the sedimentary environment is of stable structural setting, belonging to marine-terrigenous facies to coastal-swamp facies. Coal-bauxite-iron structure is very common in bauxite deposits, and sedimentary bauxite is the product of deep desilication and deiorning caused by the changes of the physical and chemical environment during mineralizing process. In addition, external environment provides sufficient organic material source. Therefore, multiple geological anomalies triggered by chemical and physical changes during the formation of layered structure of ore-bearing rock series can be used as prospecting criteria for bauxites.
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