• Geology, petrography and mineralogy of explosive breccias of Sallanlatva, Kola Region

      Sidorov, M. Yu.; Kozlov, E. N.; Fomina, E. N. (2021)
      The Sallanlatva massif belongs to the group of Paleozoic alkaline-ultrabasic complexes wide spread in the Kola Region (the northwestern part of the Fennoscandian Shield). In the central part of this massif, the host ijolite and urtites contain calcite, ankerite, ankerite-dolomite and siderite carbonatites. The explosive processes that led to the formation of carbonatite breccias in the calcite and ankerite-dolomite carbonatites occurred in Sallanlatva massife in the last stages of the carbonatite magmatism. There are two types of explosive carbonatite breccias in the Sallanlatva massif: (1) glimmerite-calciocarbonatite breccias, and (2) siderite-dolomite breccias. Analysis of the mineral composition of fragments and matrix and the shape of fragments in breccias has shown that the first material to intrude into the host calcite and ankerite-dolomite carbonatites was calcite melt. After that, dolomite melt penetrated through the fracture zones, which resulted in the formation of siderite-dolomite breccias. The differences in the mineral composition of the breccia matrix suggest that the residual carbonatite melts originate from separate magma chambers. The chamber with calcite melt was located at great depth, and some captured glimmerite fragments were abraded during the melt upwelling. Silicate-dolomite melts lifted from a shallower depth; the captured fragments of siderite carbonatites retained their angular shape. Late hydrothermal processes yielded veins and caverns with Ba-Sr-P-S-Ti-REE mineralization in the breccias and host rocks.
    • On unique stone beaches on the Arctic coast of the Kola Peninsula

      Neradovsky, Yu. N.; Miroshnikova, Ya. A.; Kompanchenko, A. A.; Chernyavsky, A. V. (2021)
      The results of studies of 11 stone beaches on the coast of the Barents Sea in the area of the Teriberskaya Bay have been presented. The studies were carried out from 2017 to 2019. As a result of the work, the structure of the beaches, their size, the composition of clastic material and the relationship with bedrocks were studied in detail. The genetic link between beaches and sea terraces has been established. Special attention has been paid to the morphology of beach clastic material, the conditions of its formation, and its role in abrasion activity. It has been shown that the clastic material of the beaches mainly corresponds to boulders equal to 100–1,000 mm, to a lesser extent to pebbles 10–100 mm, and rarely – gravel 1–10 mm. Individual boulders reach 2,000 mm. Sandy fractions in the composition of beach sediments are practically absent. The roundness of the fragments is high, semi-circular and rounded grains predominate, the most perfect shape of the rounded fragments is a biaxial ellipsoid or egg. Perfectly rounded boulders and pebbles in some areas account for up to 30 % of beach deposits. Measurements of the parameters of the egg-shaped pebbles have shown that they are close to the parameters of the "golden section" of the egg, i. e. meet the most durable form, resistant to destruction. Thus, the process of abrasion of the beach debris is directed towards their acquisition of the most energetically stable state. This suggests that the original shape of the debris contained a solid core in the form of a biaxial ellipsoid.
    • Seismic hazard assessment for the underwater gas pipeline route in the water area of the Nevelskoy Strait

      Kovachev, S. A.; Krylov, A. A. (2021)
      The presence of seismic threat multiplies the environmental hazard, especially for oil and gas production and transport facilities in water areas. Currently, there are no normative maps of general seismic zoning of the water areas of the inland and marginal seas of Russia, especially since there are practically no maps of detailed seismic zoning and seismic microzoning of even individual parts of the water areas. Taking into account the fact that intensive development of offshore oil and gas fields and the Northern Sea Route has begun, the development of such maps becomes a very urgent scientific and practical task. The seismic hazard assessment for the submerged crossing was carried out in 2008. The initial seismic effects were calculated using a probabilistic seismic hazard analysis based on five models of seismic zones and three types of models of attenuation of peak and spectral accelerations. The results of the performed calculations, including deaggregation, have shown that the initial seismicity of the area of the gas pipeline crossing route through the Nevelskoy Strait for a return period of 1,000 years is lower than indicated on the OSR-2016-B map, where the eastern end of the crossing route through the strait is characterized by the initial seismicity equal to 9 points. The soil conditions (seismic microzoning) have been taken into account by three different methods: the seismic rigidity method, the calculation method, and the method considering the thickness of Quaternary deposits. The present studies show that seismic effects vary along the pipeline route from the mainland to Sakhalin Island from 8.4 to 8.9 on the MSK-64 scale for the recurrence period of seismic shaking T = 1,000 years and from 9.3 to 9.7 points for T = 5,000 years.
    • Peculiar features of the supracomplexes formation in the Keivy domain

      Kozlov, N. Е.; Sorokhtin, N. О.; Martynov, E. V.; Marchuk, T. S. (2021)
      The Keivy domain (the northeastern part of the Arctic zone of the Fennoscandian Shield) during the period of the maximum manifestation of the Late Archean collisional processes was overlapped by tectonic allochthons of adjacent microcontinents thrust over it, submerged relative to other blocks of the continental crust, and acquired the features of a classical middle massif. In the process of studies that allow a detailed description of the formation of the supracrustal complexes of the Keivy structure, it has been found that the formation processes of the Kola orogeny had a pronounced spatial and temporal zoning and impulsive character. The maximum degree of orogeny was experienced by the rock associations of the Murmansk domain, as a result of which terrigenous material transported from its mountain slopes prevailed in the metasedimentary complexes of the Keivy domain throughout the entire period of their formation. The substance removed from the Murmansk domain was more actively accumulated in the metasedimentary rocks of the Lebyazhinsky suite; then a regular attenuation was observed within all domains, but at the last stage of the formation of the section of the Keivy sedimentary strata, the structural-material complexes of the Murmansk domain again begin to degrade more actively. A detailed study of the compositional features of the supracrustal complexes of the Keivy structure refutes the currently emerging point of view on the coeval formation of alkaline granites and felsic metavolcanics of the Lebyazhinsky suite. It can be argued with a high degree of probability that the rocks used to draw this conclusion (for which the age of 2.678 ± 7 Ma) is not typical of the supracrustal section of the metavolcanics of the Lebyazhinsky suite and are metasomatites.
    • Comparison of isotope data obtained with Sm-Nd and Re-Os methods for minerals and rocks from the Ozernoe ore occurrence, Salla-Kuolajarvi belt

      Kalinin, A. A.; Kaulina, T. V.; Serov, P. A. (2021)
      Sm-Nd isochrone, drawn for rock-forming and sulfide minerals from the Ozernoe ore occurrence, indicates albitite age of 1,759 ± 11 Ma. It shows synchronous formation of albitite and sulfide mineralization, and fully corresponds to the earlier defined age of rutile in albitite (1,757 ± 7 Ma U-Pb, n = 3, MSWD = 0.2), and Rb-Sr isochrone age 1,754 ± 39 Ma for biotite, apatite, albite, and WR. Recently published Re-Os ages of molybdenite 1,872 ± 23 Ma and chalcopyrite 1,891 ± 230 Ma indicate more ancient age of sulfide mineralization. These figures are in conflict with the age of rock-forming minerals, defined with Sm-Nd and Rb-Sr methods. The possibility of use of molybdenite from the Salla-Kuolajarvi belt for rock dating has been considered, and low reliability of Re-Os method for it has been shown. The reasons are the following: 1) extremely uneven distribution of Re in molybdenite, where Re content varies 1 wt.% even within one and the same grain, and 2) openness of the Re-Os system after molybdenite crystallization, Re is mobylized and partly removed from the mineral in the zone of hypergenesis. Removal of Re from molybdenite promotes erroneous ancient age of the molybdenite. According to the equations of radioactive decay, the age would be 110–130 Ma bigger if 5–6 % of Re is taken away. The conclusion is that molybdenite must be studied in detail, proved to be homogenous and unaltered, before it is used for Re-Os dating. In the other case the results will be not reliable.
    • Separate deposition of metals from highly concentrated solutions with granulated magnesia-silicate reagent

      Kremenetskaya, I. P.; Ivanova, T. K.; Gurevich, B. I.; Novikov, A. I.; Semushin, V. V. (2021)
      Multi-stage deposition of metals from a sulfate solution with a high concentration of iron, aluminum, copper, zinc, and nickel has been studied. The concentrations of the components correspond to the composition of the sub-basement waters of the Gaisky GOK. Granular magnesia-silicate reagent based on serpentinite (Khalilovsk magnesite deposit, the Orenburg region, Russia) has been used as an alkaline agent. The magnesia-silicate reagent's ability to reduce the acidity of solutions is due to the presence of products of destruction of the original serpentine mineral, mainly magnesium oxide. The results of the solutions multi-stage purification from metals simulation have been presented. It has been found that the reagent did not wholly exhaust its activity during a single contact with the solution. Therefore, the possibility of its repeated use for the 2nd and 3rd time has been studied. As the solution is neutralized according to the known pH range of the beginning and complete deposition of metal compounds, first iron, and then aluminum are deposited. For copper and nickel, the effect of co-precipitation is observed until the pH of precipitation of poorly soluble compounds is reached. Iron is the main component of precipitations at the 1st, 2nd, and 3rd stages, which corresponds to pH = 2.4–3.7. At the 4th stage (pH = 4.0), the precipitations consisted mainly of aluminum compounds. The copper and nickel content in precipitations increase due to decreased concentration of major components (aluminum and iron) and a pH increase. The deposition of zinc from the solution occurs not to the precipitations, but on the granules surfaces. Precipitations enriched in aluminum and iron have been obtained. Sorption and co-precipitation processes have been observed for copper, zinc, and nickel, which prevents individual precipitation by these metals. Thermally activated serpentine minerals can be considered a promising alkaline reagent for technogenic solutions neutralization and purification.
    • Chemical amelioration of nepheline sands using sewage sludge from a regional wastewater treatment plant

      Gorbacheva, T. T.; Lusis, A. V.; Ivanova, L. A. (2021)
      The studies on the use of municipal wastewater sludge as an unconventional chemical ameliorant with a fertilizing effect were carried out on ore dressing waste ("tailings") of the apatite-nepheline plant ANOF-2 KF JSC "Apatit" with a predominance of nepheline sands in their composition. The tailings dump is included in the list of objects of accumulated environmental damage in the region, but due to its rich mineral composition, it is recognized as a technogenic deposit subject to conservation for the prospect of obtaining apatite, nepheline, sphene, aegirine and titanomagnetite concentrates. In the work, the method of phytotesting of soil irrigated with unfiltered rainwater with fragmentary application of sewage sludge of a regional wastewater treatment plant enterprise has been applied. The experiments have been carried out on a single-species seed recommended for reclamation of disturbed territories in the northern regions. During the formation of a sown phytocenosis from meadow timothy (Phleum pratense L.) on nepheline sands, the stimulating effect of sewage sludge on the nutrient regime of the soil is confirmed. After phytoextraction (at the end of the experiment), it retains a high residual pool of basic nutrients (N, P, K), which indicates a prolonged action of sewage sludge. To confirm the effect obtained in laboratory conditions, a field experiment has been laid at the ANOF-2 reserve tailing dump in 2019, observations are continuing.
    • Assessment of the green spaces' state in the impact zone of the Pechenganikel smelter, the Murmansk region

      Isaeva, L. G.; Sukhareva, T. A. (2021)
      The study of the state of green spaces in urbanized areas is important due to their sanitary, hygienic and aesthetic role in the harsh climatic conditions of the Arctic. The objects of research were the green spaces of the urban-type settlement Nikel (the Murmansk region). The assessment of the distribution of tree and shrub species by categories of life state was carried out; revealed damage to leaves by atmospheric emissions, insects and fungi. A high degree of damage from pollution was noted in birch, mountain ash and bird cherry; aspen up to 85 % damaged by aphids; mechanical damage to the trunks was noted in about 26 % of the surveyed trees; 5 % of trees have frost cracks in the trunk. In the course of a comparative assessment of the chemical composition of birch leaves growing in the urbanized territory of Nikel and in forest ecosystems along the gradient of atmospheric pollution in the impact zone of the Pechenganikel plant, it was found that the concentrations of pollutants in birch leaves in technologically disturbed areas exceed background values. Birch leaves in the southern direction from the plant accumulate higher concentrations of Ni, Cu, Pb, Co, Fe than in the western and northern directions. In 2019, the concentrations of heavy metals in birch leaves increased compared to the previous study period (2004). In the urban area, the content of pollutants exceeds not only the values of the regional background, but also the levels identified in forest ecosystems along the gradient of atmospheric pollution. Concentration coefficients Cc show abnormally high values for Ni, Cu, Pb, Co, Fe; the maximum Cc values are noted for Ni and Co.
    • Investigation of the solubility of dust particles in soil solution at different temperatures (on the example of the tailings of the loparite ores' concentration)

      Maksimova, V. V.; Krasavtseva, E. A.; Masloboev, V. A.; Makarov, D. V. (2021)
      A number of large mining enterprises are located on the territory of the Murmansk region. Dusting overburden dumps and tailings storage sites leads to a complex of long-term consequences for the environment. The output of the silty fraction (–0.071 mm) of "stale" tailings of loparite ore dressing (the first field of the tailing dump) is about 22 %. The investigated material is represented by nepheline, microcline, aegirine; loparite, analcime are diagnosed in impurity quantities; the average content of cerium, lanthanum, neodymium – rare earth elements of the light group – 0.18, 0.03 and 0.015 %, respectively. In laboratory conditions, a simulation of the ingress of a fine fraction of loparite ore dressing tailings into the soil has been carried out; the interaction of tailings material with distilled water and water extract from conditionally background soil at different temperatures has been studied. In the course of the study, it has been found that the introduction of dissolved organic matter intensifies the processes of destruction and partial dissolution of the aluminosilicate matrix of rock-forming minerals; an intensive transition of rare earth elements and heavy metals into soluble forms has been recorded. The research results indicate the ecological danger of the finely dispersed material of "stale" tailings of loparite ore dressing due to the ingress of dust particles into the soil and their interaction with soil waters.
    • Lithological characteristics of modern sediments in the southwestern part of the Kara Sea shelf

      Chikirev, I. V.; Tolstobrov, D. S.; Sorokhtin, N. O.; Nikiforov, S. L.; Meluzov, A. A.; Ananiev, R. A.; Dmitrevsky, N. N. (2021)
      In August – September 2020, during cruise 49 of the R/V Akademik Nikolay Strakhov, comprehensive geological, geophysical, hydroacoustic, geomorphological and hydrophysical research studies of the western segment of the Arctic zone within the Pechora and Kara Seas began in 2018–2019 were continued. As previously, the work was aimed at mapping the relief and modern sediments in order to assess the possible negative consequences of changes in natural conditions on the Arctic coast of the Russian Federation. The main purpose of the research was to assess the evolution of natural environments within the southwestern part of the Kara Sea shelf in connection with the observed global climate change in the Arctic, as well as with the expected increase in anthropogenic load on the Arctic shelf due to the development of oil and combustible natural gas fields. Bottom grab and a shock ground tube were used to obtain samples of recent sediments of the Kara Sea. The sampling sites were determined based on the analysis of data from bathymetric bottom survey and continuous seismic profiling. During the research, the boundaries of the distribution of various facies of bottom sediments within the southwestern part of the Kara Sea shelf have been clarified. The main feature of the modern bottom sediments in the southwestern part of the Kara Sea shelf is a wide areal distribution of thin facies – pelitic muds. Along the eastern and southern coasts of the Archipelago Novaya Zemlya, a distribution zone of iceberg sediments with a width of at least 150 km has been established. The formation of icebergs should be associated with the movement of the Novaya Zemlya cover glacier, formed 30–20 thousand years ago during the Sartan Ice Age. As the studies have shown, the general Holocene transgression in the Kara Sea was periodically replaced by short regressions, at least in the southwestern part of the basin.
    • Sulfur isotope signatures of sulfides from the Khibina and Lovozero massifs (Kola Alkaline Province, Fennoscandian Shield)

      Huber, M.; Mokrushin, A. V. (2021)
      The sulfur isotope geochemistry of the Khibina and Lovozero agpaitic massifs provides an opportunity to understand the role of plume-lithosphere interaction processes responsible for the Paleozoic alkaline igneous activity in the north-eastern part of the Fennoscandian Shield. The stable sulfur isotope δ 34S analysis using triple collector isotope ratio mass spectrometer (IRMS) has been carried out on the pentlandite, chalcopyrite and pyrite from nepheline syenites. The δ 34S values for pentlandite from Khibina rocks range from +0.69 to +2.06 ‰ relative to the Vienna Canyon Diablo Troillite standard (VCDT), and the pyrite has significantly higher δ 34S values up to +4.92 ‰ VCDT. The pentlandite from the Lovozero samples has value +1.48 ‰ VCDT, δ 34S values of chalcopyrite is +2.85 ‰ VCDT. The maximum positive δ 34S values are obtained for Lovozero pyrite, which vary from +5.41 to +6.30 ‰ VCDT. Comparison of sulfur-geochemical features of Khibina and Lovozero nepheline syenite with δ 34S data for the carbonatites from the Khibina, Sallanlatvi, Seblyavr, Vuoriyarvi, Salmagora and Kovdor massifs show later carbonatite formation relatively to associated alkaline rocks. Geochemical sulfur isotope δ 34S investigations emphasizes that parental magmas of the Khibina and Lovozero alkaline massifs were derived from a metasomatized subcontinental lithospheric mantle (SCLM). We suggest that high-?34S signature on the SCLM (δ 34S of +1 to +6 ‰ VCDT) can be explained by subduction of the high-δ 34S Archaean crust.
    • U-Pb age and trace elements composition of titanite from granites of Belokurikhinsky massif, Gorny Altai

      Skublov, S. G.; Mamykina, M. E.; Rizvanova, N. G. (2021)
      As a result of isotope-geochemical study, the age data (U-Pb method, ID-TIMS) of titanite from the first phase granites of the Belokurikhinsky granite massif, Gorny Altai, were obtained for the first time. The concordant value of the titanite age of 255 ± 2 Ma coincides within the margin of error with the previously published results of dating micas from granites of the second and third phases of the Belokurikha massif by the Ar-Ar method (250 ± 3 Ma). At the same time, the results of dating differ significantly from the previously published age values for the granites of the Belokurikha massif (232 ± 5 Ma, U-Pb method for the monofraction of zircon grains; 245 ± 8 Ma, Rb-Sr method for the whole rocks). Therefore, there is every reason to narrow the time interval of the formation of the Belokurikha granite massif to 255–250 Ma. The study of the trace element composition of titanite by SIMS demonstrated their zonal structure. The central part of the titanite grain differs from the rim by a noticeably higher content of REE, Cr, Y, and Nb. The content of V, Zr and Ba decreases to a lesser extent towards the rim, the content of Sr and U remains constant. At the same time, the REE distribution spectra in the central and rim parts are conformal to each other, having a convex spectrum for LREE and a concave one for HREE. Titanite is characterized by a negative Eu-anomaly, the depth of which decreases to the rim of the grain. A negative Eu-anomaly indicates the co-crystallization of titanite and plagioclase. The REE distribution spectra in titanite from the Belokurikha massif correspond to the characteristics of a typical magmatic titanite from granitoids and differ significantly from the distribution spectra in metamorphic titanite.
    • Seasonal variability of sulfate ions in the Volga River water

      Seleznev, V. A. (2021)
      In the Volga River water, sulfate ions rank second among the main anions in terms of their contribution to water mineralization. To study the seasonal variability of sulfate concentration, an analysis of long-term data of hydrological and hydrochemical observations obtained on the River Volga (in the outlet section of the Kuibyshev reservoir) has been carried out. For the period of 2001–2018 the average annual water consumption in the dam section varied in the range of 6.2–9.0 thousand m3/s, the average annual concentration of sulfates was 55 mg/dm3, the highest – 64 mg/dm3, and the lowest – 45 mg/dm3. The content of sulfates in the reservoir is formed mainly under the influence of the Volga River water coming from the Cheboksary reservoir and the Kama River water coming from the Nizhnekamsk reservoir. The sulfate content is characterized by significant seasonal variability. During the winter low-water period, the highest concentrations of sulfates were observed with a maximum in April, before the beginning of the spring flood (67 mg/dm3). During the flood, the content of sulfates decreased, reaching the lowest values during the summer low-water period in August (44 mg/dm3), and then, from September, the concentration of sulfates gradually increased, reaching 57 mg/dm3 at the beginning of the winter low-water period. Over a long-term observation period, the amplitude of sulfate fluctuations was 34–87 mg/dm3, and its value depended on the water content of a particular year. In dry years, the concentration of sulfates in the water increased, and in dry years, it decreased. In the seasonal context, the main differences in sulfate concentrations in dry and high-water years occurred during the spring flood and winter low-water period, and during the summer – autumn low-water period, the differences became minimal.
    • Petrographic structures: Khibiny ijolites and urtites

      Voytekhovsky, Yu. L.; Zakharova, A. A. (2021)
      In addition to the standard description of the structures and textures of crystalline rocks the mathematical approaches have been proposed based on a rigorous determination of the petrographic structure through the probabilities of binary intergrain contacts. In general, the petrographic structure is defined as an invariant aspect of rock organization, algebraically expressed by the canonical diagonal form of the symmetric Pij matrix and geometrically visualized by structural indicatrices – surfaces of the 2nd order. The agreed nomenclature of possible petrographic structures for an n-mineral rock is simple: the symbol Snm means that there are exactly m positive numbers in the canonical diagonal form of the Pij matrix. New types of barycentric diagrams have been proposed. To describe the massive texture, the concept of Hardy – Weinberg equilibrium has been proposed. This boundary classifies barycentric diagrams into areas within which canonical types of Рij matrices and topological types of structural indicatrices are preserved. The change in the organization of the rock within a type is quantitative, the transition from one type to another means structural restructuring. The methods are used to describe ijolites and urtites of the Khibiny massif, the Kola Peninsula. In the modern taxonomy of rocks, the boundaries between them are mostly conditional and are drawn according to the contents of rock-forming minerals, for example, between ijolites and urtites – according to the contents of nepheline and pyroxene. The strict definition of the petrographic structure proposed by the authors makes it possible to introduce into petrography the constitutional principle (structure + composition), which is successfully acting in mineralogy.
    • Natural risks and monitoring systems: Case study of the mining-industrial heritage objects of Karelia (Ruskeala Mining Park), Russia

      Shekov, V. A. (2021)
      Mine workings (open and underground) abandoned during the production process become part of the environment. These objects begin to degrade in accordance with ordinary processes occurring in nature. However, such developments are often of historical value and therefore become tourist sites. They pose a serious threat to the health and life of people visiting these tourist sites, if such workings were not initially processed to safe conditions. The paper considers an example of such an object – a marble quarry with elements of underground caves – the Ruskeala marble deposit, located in Karelia. In the middle of the XX century, it was abandoned, today the "Main" quarry is a monument of the historical and cultural (mining-industrial) heritage of the Republic of Karelia. Ruskeala Mining Park has collected all the risks of degradation inherent in such a natural site. The paper has proposed solutions for monitoring the sustainability of underground objects used as museum exhibits to ensure the safety of tourists visiting them.
    • Substantiation of a rational method for drying granules in a fluidized bed and the hydrodynamic regime of their interaction with a fluidizing agent

      Nugmanova, A. A.; Aleksanyan, I. Yu.; Nugmanov, A. H.-H.; Maksimenko, Yu. A.; Khaybulov, R. A. (2021)
      Gluten is produced from wheat grains and is used in the food industry as an improver in flour baking properties. On the basis of a comparative analysis of the methods of dehydration of frozen granules of wheat gluten with a surface dry crust, a rational method of drying them in a fluidized bed has been selected. In the process of calculating units with a fluidized bed, its hydrodynamic parameters have been determined: loss of the pressure of the fluidizing agent; the speed at the transition of the bed from the state of rest to the pseudo-boiling mode; layer porosity; the rate of entrainment of particles in unrestricted conditions roughly corresponding to the rate of soaring, at which a single particle is in equilibrium in the gas flow. During the dewatering operation, the rate of entrainment of the granules varies; therefore, it is advisable to use the passing fluidization mode depending on the decrease in their moisture content. In the variant of the active hydrodynamic regime in the drying unit, the dehydration procedure is intensified without a noticeable decrease in the economic efficiency of its functioning and high quality indicators of the finished product with the given final moisture are provided, which is due to the specific conditions of contact of the granules with the coolant. For granules with a moisture content of 0.19 kg/kg, the values of hydrodynamic characteristics have been determined: the area of critical pseudo-boiling rates is 4.1–5.5 m/s; the carryover rate of the fines is 12.5–14.5 m/s. As a result of the study, the choice has been substantiated in favor of drying the studied granules in a fluidized bed due to the prevalence of its advantages over the dehydration of the object in drum dryers.
    • Destructive activity of hydrocarbon-oxidizing micromycetes extracted from the substrates of the coastal areas, the Barents and White Seas

      Isakova, E. A.; Korneykova, M. V. (2021)
      We analyzed the hydrocarbon-oxidizing activity of 33 micromycetes strains isolated from water and soils of the White Sea and Barents Sea coastal territories. The microscopic fungi studied were represented by the following genera: Acremonium, Aspergillus, Meyerozyma, Oidiodendron, Paradendryphiella, Penicillium, Pseudoqymnoascus, Tolypocladium, Trichoderma, Sarocladium, Talaromyces, Umbelopsis. Hydrocarbon-oxidizing activity of fungi was carried out in a laboratory experiment for two time periods: 14 and 28 days. The residual concentration of oil hydrocarbons in the medium was determined by the infrared spectrometry method. We revealed that micromycetes had different oil-destructive activity. The decrease in oil content for the strains over 14 days ranged from 11 to 83 %. Tolypocladium inflatum st.1, T. inflatum st.2, Penicillium thomii, Meyerozyma guilliermondii, P. simplicissimum, P. camemberti, P. solitum and Trichoderma minutisporum strains had the greatest oil destructive activity, reducing the concentration in the medium by 57–83 %. These micromycetes were isolated from coastal substrates, the content of oil products in which did not exceed the MPC. We found that some individual strains of microscopic fungi had high oil-destructive activity for a longer period of time: Tolypocladium cylindrosporum reduced the content of oil hydrocarbons for 28 days by 95 %. No clear relationship between the fungal biomass and the degree of decomposition of oil products was found, but some tolerant species of micromycetes can actively decompose oil hydrocarbons without significantly increasing their biomass. The identified active strains of hydrocarbon-oxidizing micromycetes can be used to create biopreparations with the prospect of their further use for bioremediation of oil spills in the northern marine ecosystems.
    • Analysis of atmospheric emissions in Murmansk and their relationship with pollution of urban lakes

      Postevaya, M. A.; Slukovskii, Z. I. (2021)
      The main sources of anthropogenic emissions into the atmosphere of Murmansk are emissions from thermal power plants and boiler houses operating on fuel oil. As a result of the analysis of the dynamics of pollutant emissions from stationary anthropogenic sources for the period 1997–2019 it has been established that the level of air pollution is assessed as low; there is a tendency towards a decrease in gross emissions from stationary sources. The main pollutants from thermal power plants are sulfur dioxide, nitrogen oxides, carbon monoxide, formaldehyde, and benzo(a)pyrene. Together with gaseous and liquid substances, fuel oil ash and products of incomplete underburning of fuel, which include heavy metals V, Ni, Cr, Pb, Fe, Sn, enter the atmospheric air. Technogenic compounds of heavy metals and other pollutants from the enterprises of the power unit, falling out with dust or precipitation on the surface and catchment areas of lakes, affect the formation of the chemical composition of surface soils, waters and bottom sediments of water bodies. This is reflected in an increase in the concentration of heavy metals (in particular, V and Ni) in the water and bottom sediments of the lakes of Murmansk in comparison with the background values.
    • Numerical simulation of the thermal regime of an underground spent fuel storage facility (built-in structure variant)

      Amosov, P. V. (2021)
      The results of a numerical simulation of the thermal regime of an underground facility for long-term storage of spent nuclear fuel in a built-in reinforced concrete structure are presented. Two computer models were constructed in a three-dimensional formulation in the COMSOL programme. The first model is based on the incompressible fluid approximation, while the second model is based on the "incompressible ideal gas" approximation. The mathematical basis of models: the continuity equation, Navier – Stokes equations averaged by Reynolds, the standard (k – ?) turbulence model, and the general heat transfer equation. Consideration of mixed convection conditions is implemented in the "incompressible ideal gas" approximation, where the air density is a function of temperature only. The most thermally stressful arrangement of spent fuel placement is investigated: U-Zr – defective – U-Be. The air rate is varied in the range from 21 to 0.656 m3/s. Numerical experiments were performed for up to 5 years of fuel storage. The principal difference between the non-stationary structure of the velocity fields predicted in the "incompressible ideal gas" model and the "frozen" picture of the aerodynamic parameters in the incompressible fluid model is emphasized. It is shown that the requirements for exceeding the temperature limit values are met when the object operates under conservative ventilation conditions (rate 0.656 m3/s) with a minimum of costs for organizing ventilation. The dynamics of heat flows directed into the rock mass through the base and from the surface of the built-in structure of the U-Zr fuel compartment to the air environment are analyzed. The predominance of the heat flow from the surface of the structure and the different times when the curves of the heat flow dynamics reach their maximum values are noted. The heat flow to the array reaches its maximum significantly faster than to the air.
    • Intertidal community of fucoid seaweeds in the Yarnyshnaya Bay, the Barents Sea

      Kapkov, V. I.; Shoshina, E. V. (2021)
      The specific and spatial structure of benthic algal community on the littoral zone in the east area of Murman coast of the Barents Sea (69°11'78''N, 36°04'38''E) has been studied in the conditions of anthropogenic influence absence. As a material for studying indicators of fucoid community and populations of dominating species in connection with habitats own long-term seasonal observations and data of scientific expeditions of 1994–2017 have served. The species composition of littoral phytocenosis consists of 39 species including 18 brown, 9 red and 12 green seaweeds, with prevalence on number of annual and seasonal species, on a biomass – perennials. Ecological factors influence essentially on seaweed distribution in different sites of the littoral zone. The major abiotic factors are presence of firm substratum, surf and storms, ice motion. Seaweed littoral community had multi-level structure, in which the basic layer was occupied by brown seaweeds with numerous litophytes and epiphytes under beds and on thallus of dominant species. The community algal biomass in the littoral zone was from 2.8 ± 0.6 up to 17.7 ± 2.9 kg/m? and depended on the species structure, substratum for benthic seaweeds, surf and tides. The biomass and density of fucoid seaweeds varied over a wide range in different biotopes under a natural rigid press of seasonal changes of environmental factors (temperature, surfs, storms) during tides and under natural damages of littoral community in the arctic region. As a whole littoral fucoid phytocenosis of the bay could be considered as an example of adaptation of seaweeds populations to the conditions of the northern seas. The received results could be useful for estimating ecological status of coastal ecosystem, at stock assessment of commercial seaweeds and for algal aquaculture development in the Barents Sea.