| UDC 551.441.571.65 |
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Prospects for Discovering ”Manto” – Type Copper Deposits in the North-East and Other Regions of Russia |
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| © 2018 A. V. Volkov |
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| Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry RAS, Mosсow |
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| E-mail:
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| The paper discusses geological-structural and mineralogical-geochemical characteristics of Cu (Ag) Manto-type deposits (MTD),is the term coined after the third main source of Cu in Chile. Ores contain not only Cu but also to first tens g/t Ag. MTD are localized in the Jurassic and Lower Cretaceous volcanogenic and volcanogenic-sedimentary sequences spread along the coastal Cordillera in Northern Chile. Typical MTD are usually represented by layered or stratiform ore deposits but sometimes include lodes, ore breccias, and stockworks. Usually Cu-rich mineralization replaces amygdules in stratiform lava flows. Paragenesis of primary ores is quite simple and is represented by chalcocite, bornite, chalcopyrite, and pyrite. Widely manifested at MTD is the crust of weathering and the secondary enrichment zone (chrysocolla, atacamite), mostly recovered by heap leaching. A remarkable feature of these deposits is almost complete absence of quartz in ore bodies. Wallrock alteration is represented by propilitization. Manto-type mineralization is deposited in the epithermal low-temperature range. The most important MTD characteristics (indicator factors of forming) are considered. Prospects for discovering MTD in Russia are discussed. |
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| Keywords: Cordillera, Chile, mine, copper, silver, Manto, volcanic zone, andesitic, lava, genesis, exploration model. |
| Full text [In Russian] |
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