Economic Geology
Seyed Mehran Heidari; Sara Safavy; Afshin Akbarpour; Azra Hassanlou; Bahram Mohaghegh
Abstract
Saveh-Razan copper (± gold) area, with WNW direction in the northwest of Urmia-Dokhtar magmatic belt, with the highest reaction to right-sided shear zones and structural trend change during the Oligomyocene, leads to the placement of semi-deep Oligomyocene diorite massifs in shallow rock depths. ...
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Saveh-Razan copper (± gold) area, with WNW direction in the northwest of Urmia-Dokhtar magmatic belt, with the highest reaction to right-sided shear zones and structural trend change during the Oligomyocene, leads to the placement of semi-deep Oligomyocene diorite massifs in shallow rock depths. It is an Eocene volcano. By creating different types of mass-related hydrothermal alteration (propylitic, intermediate-advanced argillaceous, and phyllite) along the fractures, the system concentrates the mineralizations in quartz-sulfide veins, hydrothermal incisions, and concentrated sulfide-bearing filaments. Common features of metallurgy in this area are fluid homogenization temperature between 250 to 350 ° C and salinity range of 6-28% by weight of salt, containing CO2 gas and liquid phase of liquid and the presence of sulfides such as pyrite, chalcopyrite, burnite, chalcocite and sulfosalts in related reserves. There is also more gold than silver. Therefore, these features are most similar to the mass-related intermediate-type epitermal deposits that form in calcoalkalkene magmatic arcs.
R. Mohamadi; M.H., Emami; M. Vosoghiabedi
Abstract
The area is located about 230 km of southwest of Tehran. Based of geological observations, the plutonic rocks in the area consist of Neogene (Miocene) alkaline gabbro , gabbrodiorite, locogabbro and diabase . The Oligo - Miocene calc-alkaline extrusive rocks are dacite - ryodacite , andesite trachyandesite ...
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The area is located about 230 km of southwest of Tehran. Based of geological observations, the plutonic rocks in the area consist of Neogene (Miocene) alkaline gabbro , gabbrodiorite, locogabbro and diabase . The Oligo - Miocene calc-alkaline extrusive rocks are dacite - ryodacite , andesite trachyandesite , hornblendandesite , basaltic andesite and trachybasalt .Studing on isotopic analyses of Nd and Sr indicate that surveyed area were contaminated with crustal rocks of Sialic composition . In isotopy geochemical studies, The Andesite samples are plotted in the limit of BSE; however, it seems that mantling rocks besides being settled in crust (esp. the upper continental crust) have been contaminated with in. The combination of BSE towards enrichment, from the proportion of 87Sr/86Sr has shifted; a sample of rocks shows this position. Spider diagrams related to trace elements of plutonic samples which are used for identifying the tectonic setting show intrusives are in the extensive regime; while the lavas don’t have a steady trend and are similar to subduction zones. This shows that the intrusives of the the investigated area are different genesis from the southern volcanic rocks.
