Akhtala

Other Names:
District: Somkhet-Karbagh zone
Commodities :   Copper, Barium, Lead, Silver, Zinc

The Akhtala copper deposit is located 12 km NE of Alaverdi (20 km by road) in the Lori Province of northern Armenia. Akhtala forms an ore field with the nearby Shamlug deposit.

The area is a part of the Somkhet-Karabagh “eugeoclinal” zone of Middle Jurassic submarine andesitic to bimodal volcanism and sedimentation, the result of magmatism produced by subduction of the leading edge of Gondwana beneath Laurasia. This zone can be traced, with interruptions, from Georgia (Bolnitsi district) through NE Armenia (Alaverdi, Shamlug; see LT 5032 and 5033) to the Kapan area and farther south to Iran.

It is a thick sequence of repeatedly alternating andesite with local Na-altered basalt units (“spilite”) and sodic felsic volcanics (“keratophyre”) and with units of volcaniclastics and limestone on top. It is intruded by several comagmatic massifs of gabbro, diorite, monzonite and granodiorite, and by dike swarms and it is believed that the Kapan ore field is in the roof of buried Late Jurassic intrusion.

Several erosional relics of Quaternary basalt flows occur in river valleys. Akhtala is a metal zoned system of submarine “exhalational” orebodies that are close to the Japanese kuroko VMS model. Hosted by Middle-Upper Jurassic submarine andesitic pyroclastrics and volcaniclastics (propylitized tuff breccias, tuff, andesite porphyry flows and dikes) the silicified, sericitized and chloritized rocks contain lenticular or domal bodies of internally brecciated to massive pyrite >> chalcopyrite, sphalerite > galena that are conformable with the host supracrustals. This is topped by lenses of red (hematite-pigmented) and white barite, and hematite. Barite and silicified or quartz-veined breccias contain scattered crystals of pyrite, chalcopyrite, sphalerite and galena. The Akhtala deposit was worked by underground mining during the Soviet era.

As of 2010 no tonnage information was available. Estimated endowment is of the order of 100 Kt of barite, 50 Kt Zn, 20 Kt Pb and Cu. 

(Source: Peter Laznicka, September 2012)

DM Sample Photographs

Other Descriptive Data

Akhtala 2012 - Deposit Description (986kB)

Theses