GSINET | Geological Survey of Iran , North - East Territory

Writers : Mohammadnezhad, H.; Karimpour, M.H; Malekzadeh Shafaroudi, A.
Refference : 2nd National Symposium of Iranian Society of Economic Geology
Publishing Year : 1390

Abstract :

The area is located in 55 Km of north west of Neishabur in Khorasan Razavi province. The Zak tunnel is situated in the east to east- north part of Neishabur turquoise mine. Rock units of the area are divided into three parts: volcanic, subvolcanic, and breccia units. Volcanic units include trachyte, biotite trachyte, hornblend andesite, latite, biotite latite and latite andesite.
Subvolcanic units include diorite porphyry, monzndiorite porphyry, monzonite porphyry and syenite porphyry. Breccia units include fault, hydrothermal, and volcanic breccia. These units are affected by alteration zones as silicification, silicification-carbonation, silicification-argillic, moderate propylitic, carbonation, weak carbonation- propylitic, carbonation-jarosite, argillic-carbonation, jarosite, jarosite- argillic and jarosite-argillic-silicification zones. Based on the mineralogical composition and the measured magnetic susceptibility, less altered subvolcanic� intrusive bodies and volcanic units of the area are related to magnetite series (50×10-5-474×10-5). Hypogen mineralization and oxidane zone are observed in both volcanic units and subvolcanic bodies as veinlets and disseminated type.

Subject List : Altration

Articles

Geology, alteration and magnetic susceptibility of intrusive rocks of Zak tunnel prospect area, Neyshabour Turquoise mine