Document Type : Original Research Paper

Authors

1 Assistant Professor, Geology Department, Faculty of Sciences, Golestan University, Gorgan, Iran.

2 M. Sc., Geology Department, Faculty of Sciences, Golestan University, Gorgan, Iran

3 Associate Professor, Forestry Department, Faculty of Forestry and Wood Technology, Gorgan University of Agricultural and Natural Resources, Gorgan, Iran

4 Assistant Professor, Statistics Department, Faculty of Sciences, Golestan University, Gorgan, Iran

Abstract

Grade control and ore quality determination has always been considered a challenging task for geologists and mining engineers. Ore quality is dependent on various factors such as size and geometry of a deposit, geological disturbances, and texture and ore mineralogical composition. Determination of factors which control ore grade and prediction of a suitable area are very important in terms of economics and productivity of mining operations. This study has tried to develop spatial and statistical analyses for evaluating ore quality and recognition of ore grade influencing factors at Jajarm Bauxite Mine. Through incorporating topographic, geologic and geochemical data, the effects of faults, elevation and depth on the ore grade and module (wt% Al2O3/Wt% SiO2 ratio) has been assessed. The results showed that the amounts of Al2O3 and module increased as we get closer to the faults. Furthermore, there was not any effect of faults type and strike on grade and module. A negative correlation between both elevation and depth with the amounts of Al2O3 and module indicates ore quality improvement in lowlands and shallow depths. Thus, the combination of geographic information system (GIS) methods and multivariate statistical analyses might be more efficient in geo-spatial assessments.

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