حسن باستانی

The aims of present study are investigation of endemic plants in Masjed-Daghi area introducing hyperaccumulator and indicator plants for gold and copper, and also describe the biogeochemical response pattern over a known mineralized site, namely the “Au- Cu” mineralization at Masjed-Daghi area. Masjed_Daghi is located in Jolfa sheet and it is underlain by Eocene flysch, andesite, trachyandesite, dacite, rhyodacite, Oligocene agglomerate and Quaternary deposits. Pervious researches reported copper porphyry mineralization in this area.Considering variety of vegetation in Jolfa and Masjed_Daghi, indicator plants for Cu, Pb and Zn mineralization in the study area were investigated. Mean metal contents (ppm) and mean biological absorption coefficients for Stachys inflata are: Cd 0.13- 1.18, Cu 14.8- 1.10, Pb 5.67- 0.52, Re 0.033- 4.4 and Zn 57.4- 2.50; for Artemisia sp.: Cd 0.373-1.40, Cu 22.06- 0.19, Pb 5.801- 0.12, Re 0.197- 97 and Zn 35.51- 0.48; for Moltkia coerulea: Cd 0.15- 5, Cu 24.6- 0.78, Pb 0.48- 0.06, Re 0.348- 116 and Zn 125.5- 9.65; for Astragalus sp.: Cd 0.033- 0.37, Cu 11.44- 0.21, Pb 0.513- 0.04, Re 0.089- 53 and Zn 21.8- 0.83; for Salvia sp.: Cd 0.047- 0.55, Cu 11.04- 0.46, Pb 2.6 0.19, Re 0.091- 19 and Zn 70.43- 3.42. This study presents that plants with high metal intake enabled us to obtain invaluable information about natural concentrations of chemical elements in the substrate, and to recognize new potential areas for mineral prospecting. In this study most of these plants have mean biological absorption coefficients exceeding or near to hyperaccumulating criterion >1 for most of the elements investigated. Most of the hyperaccumulator values belong to Stachys inflata and the indicating values belong to Stachys inflata, Artemisia sp., and Salvia sp.