GSINET | Geological Survey of Iran , North - East Territory

Writers : Karimpour,Mohammad Hasan;Malekzadeh Shafaroodi,Azadeh;Heydariane Shahri,Mohammad reza
Refference : 11th Symposium Of Geological Society Of Iran - Mashhad, Ferdowsi University
Publishing Year : 1386

Abstract :

Hired gold prospect area is located 160 Km south of Birjand, in eastern Iran. Exposed rocks are mainly Jurassic, Cretaceous and Paleocene sedimentary rocks and Eocene volcanic rocks are mainly andesite-dacite. Oligo-Miocene I and S-type Granitoids (gabbro- diorite-monzonite-granite) are intruded the Eocene and older rocks. Surface alteration zones are propylitic ± silisification ± sericitic, tourmaline-sericite, tourmaline-chlorite and quartz-tourmaline-sericite. At depth, alteration zones are quartz-tourmaline ± sericite ± carbonate ± chlorite.
Different style of mineralization such as stockwork, vein, replacement, and skarn are found.
Hypogene minerals are: pyrite, arsenopyrite, pyrrhotite, chalcopyrite, ± galena,� sphalerite, tourmaline, quartz, chlorite, calcite and sericite. Several types of veinlets are found, including: 1. tourmaline-bearing veinlets; 2. quartz-calcite; 3. sulfide; 4. quartz; and 5. quartz-sulfide.
Core drilling Geochemical data from target 1 and 3 show the following changes: Au = 400-5200 ppb, Ag 125 ppm, Cu = 60800 ppm, Pb = 70-20600 ppm, Zn = max 2400 ppm, Sb = 30-200 ppm, Sn = 3-580 ppm. Higher value of Sn and Au is found in Target 1.
Primary fluid inclusions are two-phase liquid-rich types in large and very large size. Temperature of homogenization of primary fluid inclusions in quartz associated with tourmaline was > 500°C, associated with sulfides >500°C, with tourmaline-sulfide between 325-365°C, and with arsenopyrite between 151-247°C.
Stockwork mineralization is found within or nearby the reduced granites (S-type). Based� on mineral paragenesis (arsenopyrite-pyhrotite), stockwork mineralization, and� High temperature of ore bearing fluid, Hired is a reduced intrusion-related gold deposit. Besides Au, the area has potential for Sn mineralization.

Subject List : gold, Altration

Articles

Alteration, mineralization and fluid inclusion thermometry of Hired Au prospect area, south Khorasan