Geochemical Distribution of Heavy Metals and Assessment of Environmental Indicators in ChahShaljami Polymetal Ore deposit, South of Birjand, Iran

The Chah-Shaljami polymetal ore deposit contains heavy metal anomalies in various mineralization zones. Geochemical distribution and correlation of elements in surficial soilsindicate that sulfide, sulfate, sulfosalt and silicate mineral occurrences (e.g. Pyrite, chalcopyrite, galena, sphalerite, molybdenite, enargite, hornblend and biotite) in mineralization and stockwork zones resulted in the strong correlation between some elements such as Fe, Mn, Mg, Ni, Pb, Zn, Cr and Sn. In addition, there is a relatively strong correlation between Cd, Ti, Ba, Al which may be related to the vein-veinlets and the intrusives. Contamination indexes (enrichment factor, geoaccumulation index (Igeo), contamination factor and modified contamination degree) were used to assess the soil and sediment enrichment in Chah-Shaljami ore deposit. These indexes indicate enrichment of S, Sb, Mn, Pb. Sulfide, sulfate and sulfosalt minerals cause strong sulfur enrichment. Cadmium is weakly contaminated as can be inferred from its paragenetic association with Pb- Zn minerals in polymetal ore deposits.