Geochemistry of Streambed Sediments of Sarbaz River, South East of Iran: Determining Sediment Provenance and its Impact on Possible Environmental Pollution

In this research the catchment of the Sarbaz river، SE Iran، has been studied to determine sediment provenance and its possible pollution potential. 30 sediment samples collected from the riverbed were analyzed for major and trace elements، using combined XRF and AAS methods. Based on major and trace element data and identification charts the sediments are identified to be of litharenite composition. Quartz-rich sedimentary and intermediate igneous origin and island arc tectonic setting is proposed for the sediments، mainly inferred from discrimination diagrams. Regarding the hazardous potential of metals and metalloids، As، Cd، Co، Cr، Cu، Fe، Mn، Hg، Ni، Pb، Se، V and Zn were studied from 30 locations. Pb، Cd and As concentrations measured respectively in 7، 10 and 20 locations are more than concentrations of the same elements in the world riverbeds. In this research، the polluted sediments were evaluated using the geo-accumulation index (Igeo). Based on this index، Cd، Pb، Zn and Cu show some degrees of pollution، while other elements are evaluated to be less pollutant. Statistic analysis show strong correlation between studied elements. Volcanic activity in north of the Makran zone can readily justify the common origin of the contaminants in the catchment of the Sarbaz river. Chromium is most probably originated from the nearby Makran ophiolites. It is concluded that geological factors have mainly been the controlling factors for the sediment pollution in the Sarbaz catchment.