ABSTRACT
The largest mountain chain in Iran, the Zagros orogenic belt, is part of the Alpine-Himalyan orogeny developed from the collision of the African-Arabian plate with the Eurasian (or Iranian) plate. The mountain range extends about 2000 km from eastern Turkey to southern Iran in a NW-SE direction and is composed of three tectonically related parallel zones: (1) the Uromieh-Dokhtar Magmatic Assemblage, (2) the Sanandaj-Sirjan Zone, and (3) the Zagros Fold-Thrust Zone (Alavi, 1994). The first 2 zones host several gold mineral deposits containing arsenic mineralization. Plate convergence and compression occurred during the period of Late Cretaceous through Paleocene and was followed by gold emplacement. During plate convergence, a thick sequence of volcanic and sedimentary rocks of variable composition were folded, faulted, and metamorphosed. Substantial thrust fault motion led to older Tethyan sea sediments and Neo-Tethyan sediments to be emplaced on younger rocks along with obducted ophiolites (Alavi, 1994).
