Geological features of gold and copper mineralization and geochemical exploration of Stream sediments and Heavy mineral explorations for gold, Kalijar, Natanz, Isfahan Province

Kalijar area is located in the North of Natanz in Isfahan Province. A number of igneous rocks have been occurred in two stages in this region. The first stage of volcanic rocks is include andesite bearing biotite, andesite bearing amphibole and green colour toffs (Eocene- Miopeliocene) and the second stage of plutonic rocks is include diorite, granodiorite bearing - hornblend and quartz monzonite (Oligo-Miocene) age in the area. The several alteration types have occurred in the area such as the sericitic, argillic and propylitic (chloritic and epidotic) that they are proximal to the fault units. The current alteration of index minerals are characterized by XRD analysis. Based on this approach, they are include calcite, quartz, alkali feldspar (Na-Ca), mica, hematite, dolomite and clay minerals. Geochemical exploration of stream sediments and heavy mineral methods were used to explore gold and copper mineralization in the area, which in the first stage 28 geochemical and 11 heavy mineral samples were taken and 68 geochemical and 18 heavy mineral samples in the second stage. The results which are gained by lab analysis by samples by ALS Chemex in Canada in ICPMS method to determine for rock forming and mineralizing minerals revealed the anomaly of Zn, As, W, Cu, Mo, Au, Ag, Pb elements in the area. The Spearman correlation coefficients has revealed the highest correlation between Fe,V(0.94), Pb,Zn (0.76), Mo,W(0.75), Cu,AS- (0.60) and W,Cr (0.81). Gold has shown the magximum correlation to Tungsten (0.54). Gold low correlation to the other metals, no correlation to rock forming minerals, represent the independent distribution of this element. Cu, Fe, Pb, Au have shown anomaly in heavy mineral studies. Nt-11, 35 ppm and Nt-12, 20 ppm of gold sampling have been harvested in this area, Two samples have been harvested from diorite mass borders (tuff rhyodacite unit) and andesite trachyte dyke to porphyrite, respectively. Geochemical anomaly maps indicates the highest gold concentration in south and the highest copper concentration in north. So they are possibly the best option for choosing the possible gold and copper mineralization. Gold mineralization to argillic alteration, copper mineralization to propylitic alteration had been shown on the basis of anomaly geochemical mineralization study. Gold and copper hydrothermal mineralization and their alteration association are related to hydrothermal solution in intrusive diorite mass (Upper Oligocene) age in northern area.