关键词: 铝土矿, 预测资源量, 潜力区, 地质参数体积法, 成矿区带

Abstract: Bauxite is the main source of aluminum and China ranks among highest in bauxite production and reserve in the world. In order to evaluate Chinas total bauxite resources and to make rational industrial policy, it is necessary to assess bauxite resource potential. Bauxite deposits in China can be classified into sedimentary, accumulative and lateritic types, of which sedimentary bauxite is the dominant one accounting for more than 80% of the total resource. The main ore forming epochs of sedimentary type are Carbonaceous and Permian while accumulative and lateritic types primarily occured in the Quaternary. The genesis of bauxite is closely related to carbonate or mafic basement and controlled by lithofacies paleogeography, paleoclimate, palaeogeomorphology and other factors. In this work, we delineated 18 metallogenic belts based on geological data, recognizing the Shanxi fault lift, southern margin of the North China Craton, and the southwest Guangxi, central south Guangxi and central Guizhou areas as the most important bauxite metallogenic belts. In addition, we analyzed prediction factors of 3 types of bauxite deposits and built prediction models for typical deposits. We assessed bauxite resources using ore deposit model combined with synthetic information prediction method, i.e., using information technology (especially GIS) to extract mineralization information and compile maps of prediction factors for quantitative prediction. We applied oreforming geological body volumetric method to estimate potential resources to the depth of 2000 m below surface. The results showed that the mineralization potential was still great up to 1000 m below surface and the identified resources to date accounts for only 35.6% of total bauxite resources. In addition to Henan, Guangxi, Shanxi and Guizhou provinces, Yunnan, Chongqing, Shandong, Shaanxi and Hebei provinces also have great aluminum mineralization potential. Our prediction results provided scientific evidence for future bauxite exploration.

Key words: bauxite, predicted resource, prospective area, oreforming geologic body volumetric method, metallogenic belts