Petrochemistry of Igneous Rocks in Area of the Erdenetiin Ovoo Porphyry Cu-Mo Mineralized District, Northern Mongolia

Petrochemical data for the igneous rocks in and around the Erdenetiin Ovoo Porphyry Cu‐Mo deposit, Orkhon Selenge trough (part of the Mongol Okhotsk Fold Belt) are re‐examined. Magmatic activity of the trough started by Permian bimodal volcanism formed in extensional regime changed in early Mesozoic by compressional regime by intrusion of calc‐alkaline gabbro‐granodiorite‐granite of the Selenge Intrusive Complex with subsequent intrusion of Porphyry Association followed by trachybasalt‐trachyandesite alkaline series volcanics of the Mogod Formation. Permian volcanics exhibits typical continental arc characteristics, the Selenge Complex intrusion and Porphyry Association are related to calc‐alkaline, I‐type, magnetite series, medium and high K rock, and enriched in LIL, depleted in Nb, Ta, Ti and P that typical for continental arc environment. The Mogod Formation is characterized by variation in K, enrichment in Al and LIL, depletion in Nb, Ta and Ti, showing magmas derived from a sub‐arc mantle source. Pe...