Aristov V.V.,RAS Institute of Geology and Mineralogy |
Prokofiev V.Y.,RAS Institute of Geology and Mineralogy |
Imamendinov B.N.,Open Joint Stock Company NUTs Mineral'nye Resursy |
Kryazhev S.G.,Central Research Institute of Geological Prospecting for Base and Precious Metals |
And 2 more authors.
Doklady Earth Sciences | Year: 2015
Themobarogeochemical investigations revealed that quartz from the Drazhnoe deposit was formed in mesothermal conditions at depths of 3–4 km from carbon dioxide–water fluids with wide salinity variations and an admixture of methane. Several types of fluids are distinguishable on the basis of the composition of extracts: hydrocarbonate–sodium, highly diluted, and late sulfate–hydrocarbonate–sodium with elevated salinity. Ore minerals precipitated in the thermostatic environments against the background of fluid heterogenization due to a probably significant pressure drop and mixing of different solutions. Metamorphic processes related to the early collision stage provided no substantial impact on the composition and potential of gold ore mineralization. © 2015, Pleiades Publishing, Ltd.
Rychagov S.N.,Institute of Volcanology and Seismology |
Davletbaev R.G.,Institute of Volcanology and Seismology |
Kovina O.V.,Institute of Volcanology and Seismology |
Sergeeva A.V.,Voronezh State Technical University |
And 3 more authors.
Journal of Volcanology and Seismology | Year: 2012
Based on a comprehensive study of the hydrothermal clay layer that occurs in geothermal fields, the conditions of formation of cation composition in argillitized rocks are discussed. Under the influence of gas-water fluids and pore solutions, micro- and nano-mineral mixtures are formed in hydrothermal clays; these mixtures include crystalline, amorphous, and transitional mineral phases. A considerable role in their composition belongs to cations of several metals (Fe, Al, Ti, Na, Mg, Ca, K, Mn, and Ba), as well as Si, C, N, S, and volatiles (F - and Cl -). The sources of cations and other elements are unaltered host rocks, newly formed hydrothermal-metasomatic rocks, hydrothermal clays, salt deposits, siliceous, carbonate, and other sediments, as well as deep fluids. In the structures of geothermal anomalies and deposits the "hydrothermal metasomatic rock-gas-water fluid-newly formed mineral chemical compounds" united system is formed. Each of the elements of this system takes part in the transportation, accumulation, and redistribution of metals. This approach to studies of the geochemistry of present-day geothermal systems may serve as a foundation for developing criteria for the presence of mineralization in metasomatites, gas-hydrothermal fluids, and new mineral associations. © 2012 Pleiades Publishing, Ltd.
Posukhova T.V.,Moscow State University |
Dorofeev S.A.,Central Research Institute of Geological Prospecting for Base and Precious Metals |
Garanin K.V.,Moscow State University |
Siaoin G.,Moscow State University
Moscow University Geology Bulletin | Year: 2013
Samples from eighteen kimberlitic bodies of Russia (Archangelsk and Yakutia provinces) and China (Liaonin and Shandong provinces) were investigated. All investigated kimberlites were subdivided into four mineralogical-technological types, according to the data obtained: (1) rocks with dominant saponite (Chidviya and Lomonosov pipes), (2) high-serpentine rocks (Snegopadnaya, Aikhal, Dalnyaya, and Udachnaya pipes), (3) rocks with high levels of carbonate and phlogopite (Chernyshevsk and Botuoba pipes), and (4) rocks with a complex mixed structures (Morkoka, 23 S'ezd KPSS, Nyurba, Mir pipes and pipes of China). A recycling scheme is offered for each type of kimberlitic rocks. © 2013 Allerton Press, Inc.
Zaulochnyi P.A.,Central Research Institute of Geological Prospecting for Base and Precious Metals |
Bulaev A.G.,Russian Academy of Sciences |
Savari E.E.,Central Research Institute of Geological Prospecting for Base and Precious Metals |
Pivovarova T.A.,Russian Academy of Sciences |
And 2 more authors.
Applied Biochemistry and Microbiology | Year: 2011
A technology for tank biooxidation of refractory gold-bearing concentrate under variable temperature conditions has been improved: the temperature of the first of two stages was changed from 30°C to 34-36°C. Gold in this concentrate is mainly associated with sulfide minerals: arsenopyrite and pyrite, which underlies a low gold recovery (16.68%) as a result of cyanidation. To resolve the problem, an association of mesophilic acidophilic chemolithotrophic microorganisms and moderately thermophilic bacteria of the Sulfobacillus genus were used for the concentrate oxidation. The composition of the used microbial association was studied; it was shown that it depends upon temperature: at 42°C, the population of the mesophilic thiobacteria decreased, whereas that of thermophilic sulfobacilli enhanced as compared to 36°C. The accepted scheme of the process ensures a high extent of gold recovery (94.6%) within a short space of time for biooxidation (96 h). © 2011 Pleiades Publishing, Ltd.