pdf № 300, December

DOI: 10.19110/2221-1381-2019-12-4-11

The new data about trace elements (ICP-MS) in W-bearing granitic rocks in Shilovo-Konevsky group of massifs in the eastern part of the East-Uralian zone in Middle Urals are presented. The results demonstrate that the Uralian W-bearing leucogranites from Shilovo-Konevsky group of massifs are very close to W-bearing leucogranites from «model» rare-metal provinces of the world in major elements. The main differences are: larger Na₂O content relative to K₂O in Uralian leucogranites, which is explained by greater depth of formation, and less degree of granitic melt fractional crystallization, which is explained both by lower fluorine content and by less evolved of continental crust in the Urals.

Keywords: leucogranites, greisen tungsten-quartz-vein deposits, magmatic differentiation, Middle Urals.

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DOI: 10.19110/2221-1381-2019-12-12-19

Fumarole carbonate mineralizations from the Tolbachik dale (GFTE, Kamchatka) and from the Sand slides older eruptive center were investigated. As part of the mineralization, a rare association of aqueous chlorohydroxyl, hydroxyl carbonates and anhydrous K-Na-Mg-Ca carbonates with an admixture of sulfates, apatite and silicates of pyroclastic origin was diagnosed. The facts of the anomalous and heterogeneous isotope-geochemical properties of primary fumarole carbonates and the trend of the variability of these properties due to fumarole contamination by an exogenous-carbonate core material were revealed. It was established that the mineralization at the Sand Slides corresponded to carbonates of deep origin by isotopic properties.

Keywords: Kamchatka, fumaroles, carbonates, isotopy of carbon and oxygen.

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DOI: 10.19110/2221-1381-2019-12-20-24

The article considers examples of similarity of representatives of different lineages of organisms. Tabulata corals are taken as an example. Historical overview of the studies devoted to problems of parallelism and homeomorphy among the tabulatamorphic corals is provided.

Keywords: tabulates, homological variability, parallelism, evolution.

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DOI: 10.19110/2221-1381-2019-12-25-33

Assemblages of rodent remains obtained from sediments of Studyony locality in the western slope of the Northern Urals were studied. In the result, two stages of microtheriofauna history are described: the Byzovaya interstadial and the Last Glacial Maximum. Fauna of the termination of Byzovaya (Middle Valday) interstadial is described on the basis of studying materials from the lower assemblage. This fossil complex is the oldest assemblage of cave taphonomic type in the Fore-Uralian Subarctic. Byzovaya fauna existed when moss tundra with the some forest vegetation was widely distributed. The community is dominated by the Siberian lemming, and considerable portion of forest and intrazonal species. The composition and ecological structure of communities of the Last Glacial Maximum indicates extremely cold and dry conditions. In this fauna the collared lemming sharply dominates with significant share of narrow-headed vole remains. Collared lemmings of the Last Glacial Maximum from Studyony locality are at the evolutionary level of teeth development corresponding to morph 3 Dicrostonyx gulielmi, characteristic for animals that lived in the northeastern part of European Russia, approximately from 30 to 11 cal. ka, from the end of Byzovaya interstadial till the beginning of the Holocene. Narrow-headed voles of this interval demonstrate the size and morphotypic features of the first lower molar, characteristic for the Late Quaternary voles of northeastern Europe.

Keywords: small mammals, collared lemming, narrow-headed vole, morphology, evolution, occlusal shape of molars, Late Pleistocene, Middle and Late Valday, Last Glacial Maximum, Northern Urals, northeastern part of European Russia.

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