Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Geology, alteration, mineralization, and fluid inclusions in the Mahiroud area, SE Sarbisheh, south Khorasan province

Document Type : Original Research Paper

Authors
Javad Shahalinejad 1
Aliasghar Calagari 1
Ali Abedini 2
Rahim Masoumi 3
1 Department of Earth Sciences, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
2 Department of Geology, Faculty of Sciences, Urmia University, Urmia, Iran
3 Department of Mining Engineering, Faculty of Engineering, University of Mohaghegh Ardabili, Ardabil, Iran
10.22071/gsj.2025.532087.2207
Abstract
The Mahiroud area is located about 130 km, SE Sarbisheh, South-Khorasan Province. The host rocks bearing quartz and calcite vein-veinlets consist of volcanic lavas and pyroclastic rocks (tuff) with intermediate composition belonging to Cretaceous. Various types of alterations including silicic, phyllic, argillic, and propylitic were developed in the study area. Both hypogene and supergene mineralization processes were recognized in the area. The hypogene mineralization also in turn occurred during two distinct stages. During the first stage of mineralization, the quartz veinlets containing pyrite, chalcopyrite, sphalerite, galena, magnetite, and gold were formed. The second stage of mineralization is distinguished by the presence of pyrite-bearing calcite veinlets. In the course of supergene alteration principally minerals such as goethite, hematite, malachite, azurite, and chalcocite were developed which superimposed the former hypogene minerals. Based on microthermometric studies, the homogenization temperatures and salinities of the fluid inclusions at Mahiroud vary within the range of 97-235°C and 1.74-7.86 wt.% NaCl eq., respectively. According to the microthermometric data, boiling and mixing with near-surface waters were the important mechanisms in ore deposition at Mahiroud. Evidence acquired from geology, alteration, mineralization, structures, and textures along with fluid inclusion data in current research indicate that mineralization in this area has similarity with low-sulfidation style epithermal deposits.
Keywords
Alteration
Hypogene mineralization
Epithermal
fluid inclusion
Mahiroud
South Khorasan

Subjects

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Scientific Quarterly Journal of Geosciences
Volume 35, Issue 4 - Serial Number 138
Winter 2025, vol. 35, Issue 4, Serial no. 138
Autumn 2025
Pages 35-50