Mineralogy, geochemistry and genesis of Qara Sabalan manganese deposit, north of Meshginshahr (Ardabil Province)

The Qara Sabalan manganese deposit belongs to the Qara Dagh-Sabalan metallogenic zone and is located in the eastern part of this zone (north of Meshginshahr). Geology of the area include volcanic (pyroclastic) rocks and the small outcrop of sub volcanic bodies (quartz-monzodiorite) with Eocene to Oligocene age. Mn deposit is hosted within the trachyandesite and tuff. Mn mineralization occurs as veins-veinlets, disseminated cement filler of brecciated zones. Faults and fractures with the trend of NE-SW have played a major roles for the formation of manganese mineralization. The main manganese mineralization consists of pyrolusite, manganite, psilomelane, hematite and goethite. variety of textures, such as open-space fillings colloidal, nodular, replacement and brecciation, are observed which are evidences for epigenetic manganese deposition. Rare earth elements patterns show a specific negative anomaly of Ce (0.04-0.13, mean 0.08) and a relatively positive Eu anomaly (0.28-0.38, mean 0.32). The significant geochemical characteristics of ore, such as Mn/Fe (mean 41.22), Co/Ni (mean 5.24), Co/Zn (mean 0.28), U/Th (mean 0.68), La/Ce (mean 1.77), Lan/Ndn (mean 2.82), Dyn/Ybn (mean 3.16), LREE/HREE (mean 9.51), ΣREE (mean 63.70), reveal a hydrothermal source for Qara Sabalan Mn mineralization.