Kahang prospect is located near the village of Kahang in Isfahan province, central Iran. DORSA Pardazeh company (the exploration license holder) discovered Kahang porphyry type alteration system (5km by 2.5km) in 2002 by mapping hydrothermal alterations using Landsat-TM satellite imagery data. Kahang lies in the central part of the main volcanic arc of Iran, which is also known as the Urumieh-Dokhtar Magmatic arc. The Urumieh-Dokhtar arc is one of the main subdivision of  Zagros orogenic belt and  product of subduction and closure of new Tethys ocean. It hosts all of the large porphyry copper deposits including Sarcheshmeh, Meiduk, Sungon and Dareh Zar in Iran.

Processed Aster data showing hydrothermal clay alteration in red pixels are Kahang prospect.

Previous Exploration:

The exploration activities, so far completed in the three zones of Kahang area (East, Central and West), are mostly comprised of detailed geological/alteration mapping (1:10000, 1:5000 and 1:1000 scales), topographic mapping (up to 1:1000 scales) systematic geochemical survey (about 350 surface soil/rock sampling and ICP analysis for 45 elements), geophysical surveying (12 pole-dipole IP/RS profiles of some 6 line km and about 1000 magnetic stations), petrological studies and trenching (~400m2), leading to deep drilling (in total 2138m in 12 holes). In addition, in order to access the drill sites about 3km roads were constructed.

Mineralization: The main type of mineralization at Kahang prospect is Cu-Mo porphyry, hosting by strong quartz-sericite and quartz magnetite alterations in quartz monzinite and diorite porphyry as well as by hydrothermal tourmaline breccia pipes. The visible copper (malachite and Cu-Mn oxides) and iron oxide mineralizations (mostly jarosite, hematite and goethite) occur in the intense zones of quartz stock working, quartz-sericite alteration and hydrothermal breccias zones. Although there are some local supergene and oxide mineralization, drilling data indicated the possible large scale economic mineralization is mostly hypogene in origin.

There are three porphyry centers (East, West and Central) at Kahang. The magnitudes of the surface soil anomalies at these three centers are:

West Kahang (500m by 500m) :     > 200 ppm Cu; 15 -182 ppm Mo
Central Kahang (600m by 450m ): >290 ppm Cu; 30 to >100 ppm Mo

East Kahang (400m by 350m):      >200 ppm Cu; 30 to >100 ppm Mo

Drilling:

East Kahang: The predominant rock type mapped in East Kahang is dacite porphyry that is intruded by a small stock diorite, both showing qurtze-sericite alteration. In outcrop the dacite porphyry has quartz eyes and its texture is a breccia with both angular and rounded clasts cemented by tourmaline. Tourmaline breccias show strong Cu-Mo mineralization.

Drilling results are as follows:

DH02(188m depth): 30m @ 0.32% Cu from 148-178m
DH09(350.4m depth): 22m@ 0.8% Cu and 110 ppm Mo from 66-88m; 16m @ 0.3%Cu from 96-112m; 16m @ 0.4%Cu from 126-140m; 26m @ 0.15% from 324-350m (min. is open at depth)
DH11(400.1m total depth): 218m @ 0.4% Cu from 182-401m including 83m @ 0.6% Cu and 90ppm Mo from 318-401.1m (mineralization is still open at depth)