Distribution Pattern of the Heavy Metals in Stream Sediments at the East and Southeast of Angouran Mine, West of Zanjan

In order to assess the concentrations of heavy metals in stream sediments of eastern and southeastern drainages of the Angouran Zn-Pb mine, stream sediment samples were selected from 77 stations. Results of samples analysis demonstrate that concentrations of As, Sb, Cd, Pb and Zn are higher and Co is less than the averages of upper continental crust in most stations. The elements correlation analysis indicates that there are intermediate to very strong positive correlations between Pb, Zn, Cd, Sb and As, and Co has no correlation with other elements. Investigation of distribution maps, enrichment factor and geo-accumulation index demonstrate that the highest enrichment and pollution in the study area related to Pb, Zn, Cd, Sb and As which are concentrated at the northern and northeastern parts of the study area (Allahlou-Chay catchment). Investigation of the relationship between the obtained data and geology of the study area demonstrates that the origin of these elements concentrations are geogenic and related to mineralizations and alterations. Exploitation activities at the Angouran Zn-Pb mine caused increasing the concentration of heavy metals and their entry into the surface waters which with the result of expansion of mentioned elements to northeast of study area and Allahlou-Chay catchment.