pdf № 303, March

DOI: 10.19110/geov.2020.3.1

Ore minerals were studied in metasomatically altered amphibolites of the Harbey metamorphic complex along Skalisty stream: dislocated clinozoisite-chlorite-muscovite-albite-amphibole schists, mainly clinozoisite and quartzy rocks. Ore minerals are represented by sulfides and rare deposits of tellurides, selenides and native metals. Several stages of the sequential formation of these formations associated with hypogenic hydrothermal and hypergenic processes were identified. At an early stage of hydrothermal-metasomatic changes of rocks, high- and medium- temperature ore minerals were formed in them-pyrite, pentlandite, Ni-pyrrhotite and possibly chalcopyrite and molybdenum, associated with chlorite — ripidolite The next stage is associated with hydrothermal processes, as a result of which high- and medium-temperature formations of the gold-sulfide-quartz formation were crystallized in the altered amphibolites: pyrite, chalcopyrite, molybdenite, matyltide-galena, galena, sphalerite, bornite, pyrrhotite, relatively low-grade gold and Hg-electrum. The rocks contain medium- and low-temperature hypogenic minerals of the third stage, associated with pycnochlorite-brungsvigit and ripidolit-daphnite: Ni- and Co pyrite, claustalite-galena, melonite, merenskiite, merenskiite-melonite, hessite and acantite. At the final stages, under the influence of low-temperature hypergenic processes, native silver, covellite, acanthite, hessite, etc. formed in metasomatites.

Keywords: Harbey complex, ore minerals, metasomatites, gold.

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DOI: 10.19110/geov.2020.3.2

By statistical processing of more than 7000 complete silicate analyses new, more reliable Clarkеs of Phosphorus (P₂O₅ and P,%) and phosphorus modules for carbonate rocks and their analogues (unconsolidated young sediments and carbonate metamorphites) were calculated. These Clarkes were noticeably lower than previously calculated. For the first time, a correlation analysis of phosphorus content and values of phosphorus modules with rock-forming components of carbonate rocks was performed, which allowed to clarify the mechanism of phosphorus accumulation.

Кeywords: Phosphorus geochemistry, phosphorus modules, Clarkes, correlation analysis.

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DOI: 10.19110/geov.2020.3.3

We have chosen borogypsum for our study, which contains gypsum and silicon dioxide used in various industries. Present methods of borogypsum processing were considered. A new flotation reagent was proposed to separate the silicon concentrate from boric acid production waste. With the help of methods of mathematical planning, a multifactor experiment was carried out to reveal the optimal mode of flotation. We chose the following factors: temperature, pH, concentration of the main flotation reagent, agitation time, and also the time of flotation. The results of an experimental study of the raw material and obtained samples were presented with the help of modern physicochemical methods (spectrophotometry, IR spectroscopy, scanning electron microscopy, X-ray phase analysis), which allowed studying the chemical and mineral compositions and the structure of the samples. The new flotation concentration technology from boric acid wastes was developed.

Keywords: waste, secondary raw materials, borogypsum, silicon dioxide, gypsum, perlastane ON-60, flotation, flotation reagent, multifactor experiment.

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DOI: 10.19110/geov.2020.3.4

The article is dedicated to the geological results of a comprehensive expedition to the Polar Urals, sponsored by brothers N. G. and G. G. Kuznetsov and organized by the Imperial Academy of Sciences, Geological Committee, and Russian Geographical Society from May 22 to September 9 (old style) of 1909, as well as to the 140^th anniversary of the head of the expedition, the outstanding petrographer O. O. Backlund. The expedition faced the wide distribution of metamorphic rocks. The guiding ideas and methods of reconstructing their primary (sedimentary or magmatic) nature used by O. O. Backlund are of great historical interest. Besides, the article draws attention to the problem of rational classification of rocks, which has not been solved so far.

Keywords: the Polar Urals, Kuznetsov brothers’ expedition, metamorphic rocks, petrologic reconstructions.

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DOI: 10.19110/geov.2020.3.5

The article is devoted to the scientific biography of the prominent Russian crystallographer Yanulov Kirill Paskalievich (1920–2004), whose supervisor was the outstanding Leningrad crystallographer Osip Markovich Ansheles (1885–1957), E. S. Fedorov’s disciple. We analyzed his most important scientific achievements.

Keywords: scientific biography, Yanulov, crystallography, mineralogy.

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