The Asachinskoe epithermal Au-Ag deposit in southern Kamchatka: physicochemical conditions of formation |
| |
| Authors: | AA Borovikov AS Lapukhov AS Borisenko YuV Seryotkin |
| |
| Institution: | Sobolev Institute of Geology and Mineralogy, Siberian Branch of the RAS, 3 prosp. Akad. Koptyuga, Novosibirsk, 630090, Russia |
| |
| Abstract: | The Asachinskoe epithermal Au-Ag deposit (southern Kamchatka) is referred to as low-sulfidation in quartz-adularia-sericite in Corbett's classification. Research into fluid inclusions of its minerals gave an insight into the PT-conditions of formation and gas composition of ore-forming fluids as well as the vertical variations in these parameters to a depth of more than 200 m within a 2 km long horizontal site of the deposit ore zone. It is shown that mineral assemblages formed at 320 to <100 °C. Ore-forming hydrothermal solutions were poor in salts (3–9.2 wt.% NaCl equiv.), with NaCl being the main component. Mineral assemblages with high contents of Au crystallized at 250–175 °C. Ore-free quartz-carbonate veins formed at 80–120 °C. High-temperature (300–320 °C) veins also lack ores. Rich gold ores were deposited in the environments where ore-bearing fluids boiled, mixing with meteoric waters. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
