Geology, mineralization, fluid inclusion, and stable isotope characteristics of the Zaghar and Sarabadan Cu-(Au) skarn deposits, Tafresh, Central Iran
| Autor: | Akram Shahhosseini, Leila Hosseina, Khalil Bahar-Firouzi, Masood Alipour-Asll |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
biology
020209 energy Geochemistry Geology Skarn Epidote 02 engineering and technology engineering.material 010502 geochemistry & geophysics biology.organism_classification 01 natural sciences Diorite Actinolite Sphalerite Geochemistry and Petrology Andradite 0202 electrical engineering electronic engineering information engineering engineering Economic Geology Fluid inclusions Pyrite 0105 earth and related environmental sciences |
| Zdroj: | Ore Geology Reviews. 124:103646 |
| ISSN: | 0169-1368 |
| DOI: | 10.1016/j.oregeorev.2020.103646 |
| Popis: | The Zaghar and Sarabadan copper-(gold) deposits are located in the northern part of the Urumieh-Dokhtar magmatic belt. Mineralization occurred in contact of the post-Eocene diorite-tonalite stocks with the upper Triassic-Jurassic shale and sandstone series in the Zaghar, and lower Eocene volcanic and pyroclastic rocks in the Sarabadan. Based on field observation and mineralogical studies, three stages of mineralization can be distinguished: (1) prograde skarn; (2) retrograde skarn; and (3) supergene stages. The prograde skarn is characterized by association of andradite, diopside, cordierite, and minor actinolite. The retrograde skarn stage is divided into two sub-stages: (1) retrograde skarn I; and retrograde skarn II. The retrograde skarn I, is marked by deposition of the main alteration minerals (e.g., tremolite, actinolite, chlorite, epidote), magnetite, ilmenite, pyrrhotite, pyrite, barite, and small amount of other sulfide minerals. The retrograde skarn II or quartz-sulfide-carbonate stage, is characterized by quartz and calcite vein-veinlets associated with Cu-Au mineralization. The supergene stage is marked by Fe oxy-hydroxides, covellite, malachite, azurite, and minor clay minerals and calcite. Ore-forming fluids associated with the quartz, calcite, and sphalerite from the retrograde II stage of mineralization is represented by LVS fluid inclusions with the temperature of 218–512 °C and salinity of 6.73–59.09 wt% NaCl, and LV type fluids with the temperature of 130–215 °C and salinity of 1.70–30.00 wt% NaCl equivalent. Stable isotope analysis of quartz yielded values of −85.30 to −60.70 δD‰, and +7.82–9.60‰ δ18Ofluid, indicating that the ore-forming fluids were mainly magmatic fluids with some contributions from meteoric waters. The δ34S values of pyrite vary from +4.90–8.10‰, demonstrate that the sulfur in deposit was probably originated from the magma. The geological and geochemical features introduce the Zaghar and Sarabadan as Cu-(Au) skarn deposits are related to the magmatic-hydrothermal activity of diorite stocks within continental magmatic arc. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect