Geochemistry, genesis and behavior of the rare elements in Chah-Gheib laterite deposit, Ghader Abad, Fars Province

Authors

Department of Geology, Shiraz University, Shiraz, Iran

Abstract

The Chah-Gheib laterite deposit is formed as a result of the weathering of serpantinized peridotite of the radiolarite-ophiolite Neyriz complex. occurs in the lower part of the dolomitic limestone of the Eocene Jahrum Formation which from the bottom to top includes; serpantinized peridotite transitional, limonite, hematite and laterite zones. Based on the mineralogical investigations coupled withXRD and EPMA results, the main minerals consist of hematite, goethite, quartz montmorillonite, palygorskite and olivine. . Based investigations EPMA results Gold is accompanied with silica minerals in the limonite zone. Based on the geochemical analysis (ICP-MS), the highest content of nickel is 10870 (ppm), which is related to the laterite zone and lowest one is 2066 (ppm), related to the transitional zone. There is a positive correlation coefficient between nickel and iron, which reflecting the presence of nickel in iron oxides. Based on Al2O3-Fe2O3-SiO2 diagram, the weathering in the Chah-Gheib laterite deposit ranges from strong to middle. Based on the geochemical analysis and correlation coefficient The rare earth elements show an increasing trend from serpentinite (8.97 ppm) to the laterite zones (18.41ppm. The amounts of Ce/Ce* range from 0.65 to 1.56 in the serpentinite and laterite zones, respectively. This indicates oxidized acidic conditions for the laterite zone. The Eu/Eu* increases from serpentines (0.13) to laterite zone (0.98) ref

Keywords


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