New Findings in 
Applied Geology

New Findings in Applied Geology

Geological, Mineralogical, and Geochemical Studies in the Cheshmeh Taji Manto-type Copper Deposit, Toroud-Chah Shirin Magmatic Belt, Northern Iran

Authors
1 Masters, Faculty of Land Sciences, Shahroud University of Technology, Shahroud, Iran
2 Faculty member, Department of Economic Geology, Shahrood University of Technology, Shahrood, Iran
Abstract
The Cheshmeh-Taji copper deposit is located in the Turoud-Chah Shirin magmatic arc, situated within Eocene volcanic layers. The petrography of the igneous rocks includes andesitic and andesite-basaltic lavas, pyroclastic rocks, and diabasic dikes.
Alterations in the deposit are divided into three main categories based on timing: primary chloritization (pre-mineralization), propylitic and secondary chloritization (synchronous with mineralization), and argillic and iron-manganese oxides (post-mineralization).
Hypogene minerals include pyrite, chalcopyrite, and bornite, while supergene minerals consist of malachite, chrysocolla, and chalcocite. The main gangue minerals are quartz, calcite, and barite. Mineralization textures include vein-veinlet, replacement, and disseminated types.

Geochemical analysis shows a strong correlation between copper and sulfur (r=0.86), confirming the sulfide nature of the mineralization. The rare earth element (REE) pattern, with LREE enrichment and a negative Europium anomaly, points to a magmatic arc environment.
Three main stages of mineralization are proposed: 1) initial formation of disseminated pyrites, 2) the main phase where copper-rich hydrothermal fluids reacted with pyrite to form primary sulfides, and 3) weathering and supergene enrichment, resulting in secondary oxide and sulfide minerals.
Based on its key features, including the host rock, mineralogy, and alteration, and by comparing these with other similar deposits, the Cheshmeh-Taji copper deposit is classified as a Manto-type copper deposit.
Keywords

  • Receive Date 26 July 2025
  • Revise Date 18 September 2025
  • Accept Date 20 September 2025