Biogeochemical exploration in Sari Gunay gold deposit, Northwestern Iran

Biogeochemistry is a useful tool for assessing geochemical dispersion patterns. Sari Gunay epithermal gold deposit was selected in order to assess the application of biogeochemical exploration for gold in northwestern Iran. In this study, four sites were sampled in a profile perpendicular to mineralized vein with a control site two km far-off mineralized vein. A sample from each dominant plant species (Silene conoidea, Achillea aleppica, Crepis corniculata, Centaurea virgata) was collected in each site and after preparation, analyzed using ICP-MS method. The results show that there is an inverse relationship between distance from mineralized vein and the concentration of gold and its associated elements in S. conoidea and A. aleppica species. S. conoidea has higher concentration of gold (303 ppb) than other species, therefore this species is a preferable bioindicator for gold mineralization. Biological absorption coefficients for Au and its pathfinder among all three species are increased over Au mineralization vein and decrease in following order S. conoidea> A. aleppica> C. corniculata. There is a need for further investigation on using S. conoidea as an As-phytoextractor (As=163.5 ppm) in remediation for arsenic contaminated sites, which also might be helpful during mining and mineral processing in Sari Gunay and neighboring deposits.