Geological and geophysical (IP, RS) studies of the Vajaro copper deposit, southwest Shahrood

Authors

Exploration Department, Faculty of Mining Engineering, Petroleum and Geophysics, Shahrood University of Technology, Shahrood, Iran

Abstract

The study area is located 20 km west of Toroud, SW Shahrood. The area is also located in the Toroud-Chah Shirin zone and copper mineralization occurred as the vein and veinlets in the Eocene volcanic host rocks. Microscopic data indicates the host rock of the mineralization are andesite and andesite-basalt of Eocene age, which undergoes extensive propylitic alteration and local sericite-carbonate and iron hydroxide alterations. Mineralization occurs as scattered, veins and veinlets, and open space filling. Calcite veins with small thicknesses along with minerals fill the fractures and open spaces and show a close relationship with mineralization. Mineralization is formed in two stages, hypogene and supergene. In the hypogene stage chalcocite, bornite, chalcopyrite and magnetite, and during the supergene stage, oxide and sulfide minerals, including secondary chalcocite, covellite, malachite, azurite, and goethite, are formed in the fractures and cavities of rocks. Microthermometric data show the homogenization temperature between 121 and 200 °C. The melting temperature of ice was measured on samples, which was obtained between -1.1 and -5.8 °C, and the obtained salinity was between 1.8 up to 8.9% wt.% NaCl.The dipole-dipole electrode configuration with an electrode separation of 10m along six profiles has been done with 700 points measurements. As a result of modeling the date, the locations of the probable subsurface mineralization zones were detained by high charge ability and relative moderate to high values in the IP and resistivity. The estimation depths for mineralization is about 70 m, that supported by the drilling data.

Keywords

References

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Volume 12, Issue 1
April 2026
Pages 39-50

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