Economic Geology
Elnaz Zahmatkesh; Seyed Mehran Heidari
Abstract
Zavarian gold occurrence formed within andesitic volcanic units in northwestern Iran. The volcanic complex is in fact a part of magmatism related to Urumieh-Dokhtar magmatic belt crosscutting northwestern rim of Central-Iran zone. This system is a part of the volcanic-sedimentary sequence of the Qom ...
Read More
Zavarian gold occurrence formed within andesitic volcanic units in northwestern Iran. The volcanic complex is in fact a part of magmatism related to Urumieh-Dokhtar magmatic belt crosscutting northwestern rim of Central-Iran zone. This system is a part of the volcanic-sedimentary sequence of the Qom Basin that is formed as an intercontinental stratovolcane in a tension environment. Gold has the highest correlation with Mo, Bi, As, Sb, Ag, Cd and Cu which indicates relationship mineralization with magmatic fluids and role of bi-sulfide complexes in gold transport. Hydrothermal alteration in this area is most in the vicinity and within intrusions, and along fractures with NE-SE trending and have more intense around siliceous zones. The activity of hydrothermal system starts by alterations related to the subvolcanic intrusive, and creates the first mineralization phase by oxid-silicic alteration along the fractures. This mineralization phase continued by hydrothermal breccia with tourmaline and copper sulfide, and finally finished with high sulfide mineralization and deposition of gold mineralization in the cavities and fractures. Therefore, Characteristics of this mineralization indicate that it is most similar to epithermal related to subvolcanic deposits.
