A.I. Kozhurin1,2, T.K. Pinegina1 1Institute of Volcanology and Seismology of Far Eastern Branch of the Russian Academy of Sciences, Petropavlovsk-Kamchatsky, Russia 2Geological Institute of the Russian Academy of Sciences, Moscow, Russia
Keywords: Kamchatka, Aleutian Arc, arc-arc collision, active faults
This article presents data on active fault-related deformation of the Kamchatka Peninsula (Kamchatka, Russia), located between the converging Aleutian and Kamchatka Island arcs. It is shown that convergence of the arcs results in shortening of the Earth’s crust of the Kamchatka Peninsula in a direction transverse to the peninsula. The convergence is accomplished by underthrusting of the colliding blocks: the Aleutian Arc is underthrusting beneath the Kamchatka Peninsula, and the Kamchatka Peninsula is, in turn, underthrusting beneath Kamchatka. It is demonstrated that this mode of convergence is also characteristic of larger-scale collision zones, as in case of those between the Indian and Arabian plates with the Eurasian Plate. In all cases, the plate (block) that underthrusts is the one whose hinterland contains the driving source of motion.
U.A. Moroz1, A.V. Nikiforov1, V.V. Yarmolyuk1,2, A.M. Kozlovsky1, A.A. Ivanova3, E.B. Salnikova3, V.M. Savatenkov3, Yu.V. Plotkina3, A.K. Khertek2, N.A. Polyakov1 1Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences, Moscow, Russia 2Tuvinian Institute for Exploration of Natural Resources, Siberian Branch of the Russian Academy of Sciences, Kyzyl, ul. Internatsional’naya 117a, Russia 3Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences, St. Petersburg, Russia
Keywords: Nepheline syenite, magma differentiation, isotopic composition, geochronology, rare-metal magmatism, Central Asian orogenic belt, Sangilen
Massifs of alkaline granitoids and nepheline syenite are widespread in Eastern Tuva and are frequently associated with rare-metal deposits and occurrences, which formed mainly during the Late Carboniferous and Permian. The Naryn massif comprises nepheline syenite of the main phase, rocks of the contact zone, and a complex of three types of foidite microsyenite dikes. Zircon U-Pb geochronology yields ages of (SIMS - 315 ± 3 Ma) for the main phase and (CA-ID-TIMS - 318 ± 1 Ma) for the microsyenite-1 dikes, indicating that the massif was emplaced during the Middle Carboniferous. The mineralogical, geochemical, and Nd isotopic characteristics of the massif rocks suggest that their diversity results from the differentiation of a single parental magma, a process that occurred at different hypsometric levels. Crystallization of biotite-pyroxene-amphibole nepheline syenite of the main phase and feldspar liebnerite syenite of the marginal zone occurred at the upper level. Dikes of apo-amphibole nepheline microsyenite-1, pyroxene-biotite microsyenite-2, and biotite nepheline microsyenite-3 were emplaced sequentially from a deeper chamber containing the differentiating melt. The evolution of the melts at both levels was driven by the fractionation of mafic minerals (amphibole), apatite, and feldspar. As melt alkalinity increased, rare elements such as Zr, Nb, Ta, and REE accumulated, eventually forming their own mineral phases during the late stages of crystallization. These findings indicate that the widespread foidite-series rocks of Eastern Tuva may be potentially ore-bearing, and the Middle Carboniferous should be considered as a distinct phase of alkaline magmatism within the East Sayan rare-metal metallogenic zone. The Nd isotopic composition of the Naryn massif rocks (εNd( T ) = 6.3-7.1) precludes significant involvement of continental crust in their source. Therefore, sublithospheric alkaline basaltoid magmas are interpreted to be the parental magmas for all rocks of the Naryn massif.
A model sample of ore pyrite from the Degdekan gold deposit (Northeastern Russia) is used to demonstrate the application of different variants of inductively coupled plasma mass spectrometry for the purpose of determining the ratio of surface-bound and structurally bound trace elements in pyrite. Despite the differing physicochemical principles of the analytical methods, namely, the decomposition of crystals of varying sizes and data processing using the statistical sample of analytical data for single crystals (SSADSC) and direct surface scanning with a laser beam of varying power using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), a number of elements show a tendency to be enriched in the surface layer of pyrite crystals. The ratio of the trace element content in the surface layer to that in the volume (structure) of the crystal is defined as the selectivity of surface phases for a given element. The selectivity (S) values obtained by the first method are as follows: 3.9 (Mn), 3.3 (Ag), 6.4 (Pd), 6.4 (La), 0.3 (Pr), 0.8 (Tb), 2.6 (Ho), 0.5 (Er), and 1.0 (Lu). The LA-ICP-MS results yield the following values: 3.9 (Mn), 1.4 (Co), 6.2 (Ni), 1.6 (Cu), 0.9 (Sb), 0.2 (Au), 0.3 (As), 6.8 (Ag), 18 (La), 46 (Ce), 5.2 (Pr), 11 (Nd), 1 (Eu), and 0.6 (Dy). A comparison with experimental selectivity values for Mn, Pd, and Ag shows a reasonable agreement. Most of the studied trace elements show a direct correlation between selectivity and the difference in the ionic radii of the element and Fe, confirming the relationship between selectivity and the incompatibility of the impurity element in the FeS2 structure. High correlation coefficients are observed among light rare earth elements on the surface, whereas correlations between light and heavy rare earth elements are either absent or negative. Despite the preliminary nature of these results, they warrant practical consideration as a foundation for developing technologies to extract critically important rare earth elements as byproducts during the processing and beneficiation of pyrite ore and concentrate.
N.A. Mukhortina, E.V. Zippa
Tomsk Branch of Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia
Keywords: Polycyclic aromatic hydrocarbons, thermal waters, origin of PAHs, technogenic load, water-rock system
New data on the composition and distribution of polycyclic aromatic hydrocarbons (PAHs) in thermal waters and host rocks in the Baikal Rift Zone have been obtained. It is shown that the total concentration of all identified compounds is 0.17-1.15 μg/L in the thermal springs and 0.021-1.19 μg/kg in the host rocks. Naphthalene, phenanthrene, and dibenzo[a,h]anthracene predominate in the waters. Phenanthrene, fluoranthene, and dibenzo[a,h]anthracene prevail in the rocks. It has been established that the total PAH concentration increased with TDS of water and with N2 and He concentrations in released gases. The calculated coefficients of technogenic load show a low level of pollution for all the studied thermal springs. The PAH origin was determined based on indicator ratios. On the one hand, PAHs are petrogenic in the thermal waters; they resulted from the geochemical transformations of organic matter at high temperatures, pressures, and microbial activity and were transported with aqueous and gas condensate solutions along faults and fractures. On the other hand, some compounds are pyrogenic; the pyrolysis products get into thermal waters under near-surface conditions or during the mixing of thermal water with cold groundwaters. The results obtained give detailed insight into the composition of thermal waters and the genesis of organic matter. They can be used to propose a conceptual model for the formation of thermal water composition in the region under study.
V.N. Sergeev1, A.A. Soloviev1,2, D.V. Kudin1, R.V. Sidorov1, I.M. Aleshin1,2, F.V. Perederin1,2, K.I. Kholodkov1,2, D.K. Mokrov2, A.A. Kamaev1, A.A. Grudnev1,2, V.V. Kabrov1, V.A. Atabekyan3 1Geophysical Center, Russian Academy of Sciences, Moscow, Russia 2Schmidt Institute of Physics of the Earth, Russian Academy of Sciences, Moscow, Russia 3AO Institute of Geology and Fossil Fuel Development, Moscow, Russia
Keywords: Geomagnetic measurement, Earth’s magnetic field, measurement method, aeromagnetic survey, ground-based survey, magnetic field component, magnetic anomaly, magnetic field model verification
We propose a comprehensive field method for assessing the accuracy of the Earth’s magnetic field models. Our approach involves instrumental determination of the geomagnetic field vector elements at specific locations. The measurement complex includes aeromagnetic surveys using unmanned aerial vehicles and ground-based surveys comprising areal pedestrian magnetometry and absolute measurements of magnetic declination and inclination. The developed method enables the determination of the Earth’s magnetic field in regions with insufficient coverage by permanent ground-based geomagnetic observatories. We present the results of applying this method in the central part of the West Siberian Platform. These results confirm the effectiveness of the proposed approach for conducting high-precision measurements within time intervals constrained by seasonal and weather conditions. The resulting data exhibit high accuracy and demonstrate the potential of this method for determining the secular variation of the Earth’s magnetic field in arbitrary regions.
N.E. Biruchkov1, A.S. Serdyukov1,2, G.S. Chernyshov1 1Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia 2Chinakal Institute of Mining, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Seismic survey, reflected waves, interpolation, regularization, Fourier transformation, optimization
When conducting seismic surveys on the ground, it is usually not possible to placereceivers with a uniform sufficiently frequent step over the area of observation. Interpolation (regularization) is an effective tool for generating additional seismic records without changing the spectral composition of data over time and with expansion of the spectral composition over space. This paper considers the optimization of a regularization algorithm based on iterative application of discrete Fourier transform (DPF) over a space known as ALFT (Anti-leakage Fourier transform). The proposed modification of ALFT is a way to reduce the set of sample wave numbers when performing DPF. The effectiveness of the proposed algorithm was confirmed by processing both synthetic and field data. The calculation time was reduced several times compared to the original algorithm, and the results of restoring missed traces did not worsen. The results are valuable from a practical point of view and can be applied in future to the processing of ground-based seismic data on an industrial scale.
A.A. Dobrynina1,2, A.V. San’kov1, I.V. Buddo1, I.A. Shelokhov1, V.A. San’kov1 1Institute of the Earth’s Crust, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia 2Dobretsov Geological Institute, Siberian Branch of the Russian Academy of Sciences, Ulan-Ude, Russia
Keywords: Passive seismic methods, seismic noise, shallow subsurface, frost mound, hard-to-recover reserve, Arctic
This paper provides a brief review of methods based on the analysis of natural microseismic ground vibrations - collectively known as passive seismic methods. These include spatial autocorrelation, seismic interferometry, and the spectral ratios of seismic noise components. Their application for studying the structure and properties of the shallow subsurface in the Arctic is discussed. The shallow section across frost mounds in the Arctic is analyzed and interpreted using the spectral ratios of seismic noise components. The resulting two-dimensional sections reveal a horizontally bedded structure, with four main beds distinctly identifiable on the profiles. These beds are interpreted as an upper sedimentary bed, a basement, and two intermediate beds distinguished by their velocity characteristics. The section is disrupted by vertical and inclined heterogeneities that extend from the basement faults to the surface, exhibiting high anisotropy and reduced rigidity. The spatial correlation between these subvertical heterogeneities and the surface locations of frost mounds suggests that these areas represent zones of weakness, possibly fault zones or fluid migration pathways. A review of scientific publications suggests that the results obtained using passive seismic methods are reliable, as also confirmed by other independent geophysical techniques. Passive seismic methods prove highly effective in hard-to-reach areas like the Arctic because they do not require long-term deployment of an observation network. Furthermore, spectral ratio methods do not necessitate a large number of seismic stations. These methods are particularly useful for studying hard-to-recover hydrocarbon reserves characterized by a complex shallow structure (several meters). They enable rapid investigation of the upper section at depths ranging from a few meters to tens of kilometers during reconnaissance work, with minimal financial and labor investment. From an environmental standpoint, passive seismic methods are the least intrusive, as they are non-invasive and non-destructive.
M.O. Khmelnitskaya1, O.S. Vereshchagin1, A.G. Kopylova2, Yu.D. Gritsenko3,4, N.S. Vlasenko1, S.N. Britvin1 1Saint Petersburg State University, St. Petersburg, Russia
2Diamond and Precious Metal Geology Institute, Siberian Branch, Russian Academy of Science, Yakutsk, Russia
3Lomonosov Moscow State University, Moscow, Russia
4Fersman Mineralogical Museum Russian Academy of Sciences, Moscow, Russia
Native iron occurrences in Siberian magmatic rocks (gabbro-dolerites) have been known since the second half of the 20th century and are among the largest in the world. However, detailed data on minerals associated with native iron are lacking, and its genesis remains a subject of scientific debate. This paper examines native iron and associated anoxic minerals from magmatic rocks of Krasnoyarsk Krai (Dzhaltul, Khungtukun, Khininda, and Maimecha) and Yakutia (Aikhal), and summarizes data on accessory minerals and their genesis. In the studied samples, native iron is associated with oxides (ilmenite, magnetite, titanomagnetite, hercynite, wustite, rutile), native elements (taenite, copper, graphite, bismuth and lead), intermetallics (tetrataenite, awaruite, a compound of the Ni-Sn system close to Ni3Sn), carbides (cohenite and haxonite), germanide (olgafrankite Ni3Ge), phosphide (schreibersite), sulfides and their analogues (troilite, pentlandite, cobaltpentlandite, heazlewoodite, chalcopyrite, cubanite, chalcocite, bornite, mackinawite, weissite, orcelite, sphalerite, nickelite and sperrylite). Mineral association of native iron varies among the various massifs and is most diverse in the Dzhaltul intrusion, characterized by the presence of native mineral phases of nickel, germanium, and tin. The mineral association of native iron of the Dzhaltul intrusion is similar to those identified on Disko Island (Greenland). Based on the original and previously published results, it is suggested that native iron was formed under low-pressure near-surface conditions (pressure ~30-100 MPa) at initial temperatures typical of basaltic melt (~1000-1200 ºC), as a result of the interaction of silicate melt with sedimentary rocks rich in organic matter. Data on the geological position of the studied massifs and the established conditions of their formation indicate that igneous rocks containing native iron should be widespread within the margins of the Tunguska syneclyse.
A.V. Repin1, P.P. Bobrov1,2, N.A. Golikov3, O.V. Rodionova1 1Omsk State Pedagogical University, Omsk, Russia
2 Institute of Radiophysics and Physical Electronics of the Scientific Center of the Siberian Branch of the Russian Academy of Sciences, Omsk, Russia
3 Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: Dielectric constant, resonator method, NMR, sandstones, siltstones, clay minerals, clay content, mineral composition, chemical composition.
The paper presents the results of permittivity measurements for loose dry sand and clay minerals in the frequency range of 0.5–2 GHz. A coaxial cell, a half-wave resonator, and a ZNB20 vector network analyzer were used for the measurements. Using a dielectric mixture model, the permittivity of the solid phase of minerals was found. The permittivity of 12 solid samples of sand and siltstone rocks was measured in a capacitor cell in the frequency range of 100–500 MHz. The method for estimating the proportion of clay minerals in solid samples is based on differences in the permittivity of sand (3.8–5) and clay minerals (7.5–11) and the use of a dielectric mixture model. The rock was initially considered as a two-phase medium containing air and a solid phase, then the solid phase was considered as a mixture of sand and clay fractions. The clay content values found using the dielectric method were compared with the results obtained using the NMR method. Permittivity and density data were used to assess the mineral composition of the samples. Taking into account the chemical composition of the minerals and their content determined by the dielectric method, the contents of the main chemical elements in six samples were estimated and compared with the results obtained by scanning electron microscopy.
A.N. Dmitrievsky1, V.L. Shuster1, S.A. Punanova1 1Oil and Gas Research Institute Russian Academy of Sciences, Moscow, Russia
Keywords: Western Siberia, Baydaratskaya megatrough, oil and gas accumulation zones, catagenesis stages, organic matter, Paleozoic deposits, basement formations
This article examines the contribution of Academician A.A. Trofimuk to the development of the country's oil and gas complex, as well as his call and commitment to the "fight" for Siberian oil. The article presents the authors' research findings on the "fight for Siberian oil": identification of oil and gas accumulation zones and substantiation of the sedimentary section's potential in northern regions, including the Arctic territories of Western Siberia; a forecast of the phase state and depth of possible hydrocarbon accumulations in deep horizons based on geological, geochemical, and geophysical data, using data on Paleozoic oil and gas complexes in the southern Kara Sea and the West Siberian Oil and Gas Basin onshore. A critical analysis of the problem of Paleozoic oil, including basement oil, is provided. The mechanism for the formation of fractured rocks and oil (gas) accumulations in basement formations is examined.
B. K. Karasal1,2, T. V. Sapelkina2, A. A. Chylbak1, I. D. Karasal3 1Tuvan State University, Kyzyl, Russia 2Tuvinian Institute for Exploration of Natural Resources, Siberian Branch, Russian Academy of Sciences, Kyzyl, Russia 3Center for Biosphere Research of the Republic of Tuva, Kyzyl, Russia
Keywords: Overburden, argillite, mining method, composition, dispersivity, grindability, properties, ceramics
With a view to estimating applicability of overburden rocks of coal mining as a source of ceramics production, their quality indicators, including mineralogical and chemical compositions, hardness and dispersivity, as well as the content of components causing destructive processes and toxic gases, are analyzed. It is found that argillaceous overburden rocks experience softening and fine decomposition in dumps, which makes them better prepared for the further processing. The mineralogical and chemical compositions of argillaceous overburden is typical of natural clay. Argillaceous rocks ground to < 0.63 mm and wetted pass to a moderately plastic mass which allows shaping work pieces without defects. Baking of argillaceous rocks starts at a temperature over 900 °C, which enables manufacturing walling ceramic materials with the properties as per State Standard GOST 530-2012.
V. R. ANTIPENKO1, S. S. ZHBANOVA1, O. N. FEDYAEVA2, A. A. VOSTRIKOV2 1Institute of Petroleum Chemistry, Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia 2Kutateladze Institute of Thermophysics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: natural asphaltite, supercritical water, thermolysis, nitrogenous bases, composition
A comparative analysis of the composition of low-molecular nitrogenous bases (NBs) in high-sulphur natural asphaltite and liquid products of its conversion in supercritical water (SCW) at 400 C and 30 MPa with and without the presence of aluminium and zinc additives was carried out for the first time. Based on the results of analysis of NB extracts by gas chromatography - mass spectrometry, the trends have been revealed in the changes of structural-group and molecular composition of various NB types due to changes of the conditions of SCW-conversion of asphaltite. It has been discovered that the homologous series of basic aromatic nitrogen-containing compounds containing from two to five aromatic rings are present in all the studied NB extracts from conversion products. The addition of aluminium and zinc promotes the formation of additional amounts of non-substituted structures or the structures containing smaller total number of carbon atoms in alkyl substituents, as well as pentacyclic azabenzopyrenes, dibenzoacridines and tricyclic phenylquinolines. A change in the relative content or appearance of the above-listed NBs in SCW conversion products points to the presence of such nitrogen- and nitrogen-sulphur-containing structural fragments in the resin-asphaltene components of natural asphaltite.
V. SH. ASLANOV1, K. M. SAMEDZADE1, E. B. GAHRAMANOVA2, I. A. TALIBLI1, U. N. SHARIFOVA1 1Institute of Catalysis and Inorganic Chemistry, Ministry of Science and Education, Baku, Azerbaijan 2Azerbaijan Technical University, Baku, Azerbaijan
Keywords: catalyst, sulphur dioxide, hydrogen sulphide, natural gas, granulation sulphides
Sulphur dioxide (SO2) is one of the main atmospheric pollutants emitted from sulphide-containing ore processing and fossil fuel combustion. Efficient utilisation of SO2 is a significant task both from the environmental perspective and within the framework of industrial technologies improvement. Investigation of the autocatalytic action of sulphide phases formed on the surface of X18H9T(10T) steel on SO2 reduction using gaseous reducing agents has been carried out. Taking into account literature data, it has been concluded that during the reduction process, mainly iron sulphides (pyrrhotine (Fe1-xS) and pyrite (FeS2)) are formed on the surface of steel, as well as, to a lesser extent, sulphides of nickel (NiS) and chromium (Cr2S3). Sulphide phases formed under the action of reaction medium have been revealed to provide high catalytic activity and synergism in SO2 reduction. In the presence of iron, nickel and chromium, more active reducing agent, hydrogen sulphide (H2S) is formed, which, in turn, amplifies the synergistic effect and intensifies the catalytic process. It has been determined that the addition of Cr and Ni (up to 5 wt% of each element) to iron sulphide phases provides an increase in catalytic activity. These modified sulphides exhibit efficiency not lower than that of the sulphides formed on the surface of X18H9T(10T) steel, despite the higher content of Cr (about 18 wt%) and Ni (about 9 wt%) in the steel itself. A distinguishing feature of the process is in catalyst formation directly during reduction process, which ensures continuous renewal of its activity without the necessity of additional regeneration. The potential for using metal alloys as carriers for self-generated catalysts for sulphur dioxide utilisation is demonstrated.
O. I. BELYKH1, G. A. FEDOROVA1, I. V. TIKHONOVA1, A. S. GLADKIKH2, S. A. POTAPOV1, YA. A. NAIDANOVA1, A. V. KUZMIN1, E. G. SOROKOVIKOVA1 1Limnological Institute, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia 2Saint-Petersburg Pasteur Institute, St. Petersburg, Russia
Keywords: Baikal, cyanobacteria, cyanotoxins, saxitoxin, phylogeny, enzyme-linked immunoassay
Paralytic neurotoxins (saxitoxins) produced by cyanobacteria have been found in Lake Baikal and the reservoirs of the Angara cascade of hydropower plants. These neurotoxins are dangerous for humans and animals. The concentration of paralytic toxins was determined to be 0.2-182.6 μg/L, exceeding the limits recommended by the World Health Organisation. Cyanobacterium Dolichospermum lemmermannii was highly abundant in Lake Baikal and reservoirs of the region, its mass development causing localised surface blooms. Cyanobacterial cultures isolated from Lake Baikal were identified as D. lemmermannii. Saxitoxin biosynthesis gene sequences were detected in samples from the studied water bodies and in cultured strains; they had high similarity to each other and belonged to the single species - D. lemmermannii. This is the first report of the ability of D. lemmermannii to synthesise paralytic shellfish toxins. Four toxin variants were identified in the plankton of Lake Baikal and reservoirs: saxitoxin and neosaxitoxin containing carbamoyl groups, as well as decarbamoyl derivatives of goniatoxins. It is shown that in the ancient oligotrophic Lake Baikal and the Angara River reservoirs, there is a source of occurrence and spread of harmful algal blooms due to the presence of toxin-producing cyanobacteria. Under favourable hydrophysical and hydrochemical conditions, and influenced by climatic and anthropogenic factors, the frequency and prevalence of toxic cyanobacterial blooms in the aquatic ecosystems of the Baikal region, as globally, exhibit an increasing trend. This underscores the need for further research and implementation of significant efforts aimed at monitoring cyanotoxins and toxic bacterial species, as well as at understanding the mechanisms underlying the initiation and proliferation of cyanobacterial blooms.
R. A. BURKHANOVA (KHRIPUNOVA)
Ufa Federal Research Centre of the Russian Academy of Sciences, Institute of Geology, Ufa, Russia
Keywords: gold, rocks, atomic absorption spectrometry, decomposition methods, reverse aqua regia
The analytical and methodological problems that arise during the preparation of samples for determining the gold content in rocks are described, and possible solutions are suggested. It is determined that the accuracy of the results depends on the method of preliminary decomposition, which should be chosen taking into account the complex composition of the material under study. Decomposition methods are tested on standard samples of rocks with different mineralogical compositions, in particular, the effect of the acid ratio in aqua regia on the efficiency of gold extraction is studied. Special attention is given to atomic absorption analysis as a promising method for determining gold concentration. Treatment of the samples with reverse aqua regia (HСl/HNO3 = 1 : 3) allowed for the most complete extraction of gold. It is shown that gold extraction increases from 62 to 95 % on average with an increase in the relative concentration of nitric acid and a decrease in the concentration of hydrochloric acid.
P. N. KUZNETSOV1, B. AVID2, L. I. KUZNETSOVA1, A. V. OBUKHOVA1, E. S. KAMENSKIY1, O. A. EPOV1 1Krasnoyarsk Scientific Centre SB RAS, Institute of Chemistry and Chemical Technology SB RAS, Krasnoyarsk, Russia 2Institute of Chemistry and Chemical Technology of the Mongolian Academy of Sciences, Ulaanbaatar, Mongolia
Keywords: coal, molecular structure, surface layer composition, X-ray photoelectron spectroscopy
The features of the composition of carbon and heteroatomic functional groups on the surface of carbonification series coals, oxygen and nitrogen distribution over the surface and volume have been characterised by X-ray photoelectron spectroscopy. It has been established that oxygen in brown coals is almost equally represented on the surface and in volume. The surface of hard coals is enriched in oxygen-containing groups, and their concentration in coking coals significantly exceeds the volume concentration. Carbon is present on the surface mainly in polycondensed aromatic (graphite-like) structures. Their proportion and degree of uniformity increase with carbonification. The oxidised forms of carbon are present on the surface mainly in the form of phenolic and ether groups. Heteroatomic nitrogen-containing groups are represented by aromatic, mainly five-membered pyrrole, to a lesser extent six-membered pyridine structures. It is shown that as carbonification degree increases, the five-membered cycles in coals are transformed into six-membered cycles.
A. A. NEPOMNIASHCHII, A. V. MARKELOVA, L. A. BULUCHEVSKAIA, A. V. LAVRENOV
Boreskov Institute of Catalysis SB RAS, Center of New Chemical Technologies BIC SB RAS, Omsk, Russia
Keywords: sulphated zirconia, platinum, n-butane, isobutane, isomerisation
Platinum-containing catalysts for n-butane isomerisation based on sulphated zirconium and aluminium oxides differing by synthesis conditions were investigated. It has been demonstrated that the method of mixing initial reagents, temperature, and pH for the precipitation of precursors affect the textural properties of the supports. Precipitation in an alkaline medium at 15 °C with controlled pH (10-12) yields fine crystalline zirconium dioxide with developed specific surface area and a dominant mesoporous structure. It has been determined that, regardless of synthesis conditions, introducing 9.0 wt% sulphate groups suppresses crystallisation of the monoclinic phase and promotes the formation of the tetragonal modification of crystalline ZrO2 after calcining the hydroxide precursor at 710 °C. It has been established that the optimal reaction conditions (H2/n-butane = 0.1, pressure 1.5 MPa, temperature 160-200 °C) enable achieving a high yield of the target product, isobutene (up to 44 wt%), and avoiding excessive formation of side products.
A. V. OVCHAROVA, E. N. SAZHINA
Nizhny Novgorod State Technical University n. a. R.E. Alekseev, Nizhny Novgorod, Russia
Keywords: oil, organochlorine compounds, aqueous alkaline solution, oil desalting, electrical desalting unit
A quantitative assessment and identification of organochlorine compounds present in the oil directed for processing was performed, and an effective method for their extraction was proposed. It is shown that feeding an aqueous alkaline solution for mixing with processed oil before it enters the electrical desalting unit at the maximum admissible temperature in the electrical dehydrators (135 ° C) allows reducing the content of organochlorine compounds from 6 to 1 ppm.
N. V. PETROVA1, A. L. SHAVARDA1,2, N. A. MEDVEDEVA1,3, R. A. MURTAZALIEV4,5 1Komarov Botanical Institute, Russian Academy of Sciences, St. Petersburg, Russia 2St. Petersburg State University, St. Petersburg, Russia 3Herzen State Pedagogical University of Russia, St. Petersburg, Russia 4Dagestan Federal Research Centre RAS, Precaspian Institute of Biological Resources, Makhachkala, Russia 5State Nature Biosphere Reserve Dagestan, Makhachkala, Russia
Keywords: Dracocephalum multicaule, essential oil, γ-terpinene, p-cymene, α-pinene, 1,8-cineole, germacrene D, spathulenol, allo-aromadendrene, α-humulene
The volatile part of molecular resource of the plants belonging to Dracocephalum genus (dragonhead) of Lamiaceae family growing at the territory of Dagestan has been investigated. The subject of investigation was the component composition of essential oil in the above-ground part of Dracocephalum multicaule collected in three locations of the Akhty District (Dagestan, Russia). The yield of essential oil obtained by hydrodistillation from the dried plant raw material using a Ginsberg apparatus ranged from 0.7 to 1.2 %, recalculated for the dry weight. Analysis by gas chromatography in combination with mass spectrometry has revealed the presence of over 40 compounds, accounting for up to 99.4 % of the total amount of oil. The compounds dominating among monoterpenes were γ-terpinene, p-cymene, α-pinene, 1,8-cineole; among sesquiterpenes - germacrene D, spathulenol, allo-aromadendrene and α-humulene. It has been found that, while the component composition of the studied samples is the same, there is a significant variability in the concentrations of individual compounds.
O. M. ROZENTAL, N. D. DUBOV
Institute of Water Problems, Russian Academy of Sciences, Moscow, Russia
Keywords: groundwater, DTW algorithm, urbanised territories, chemical analytical monitoring, correlation analysis, toxic substances, dispersion analysis
A comparison of the time series of concentrations of substances predominantly of anthropogenic origin polluting the groundwater of several large territories of the Moscow urban agglomeration in aquifers located at a depth from 3 to 50 m has been performed. It has been found that not all controlled indicators tend to decrease steadily with an increase in depth, the observed changes of parameters are often insignificant, and the concentration of petroleum products, for example, increases by several times when passing to deeper horizons. This makes the notion of deep-lying water as a strategic resource ensuring the sustainable development of a city unreasonable. To identify the sources from which impurities enter deeply located horizons, the causal relationships between the chemical analytical data for groundwaters were analysed using correlation and variance analyses. To measure the similarity of these series, the dynamic time scale transformation (DTW) algorithm was applied because the time series of data for different horizons experience shifts that change over time, so that their rhythms may differ. A significant similarity in the time series of water pollutant concentrations in different aquifers has been established. On this basis, it is concluded that the rock layers separating the aquifers in the territories under consideration are permeable, which provides the possibility of the vertical migration of pollutants to deeper bedded groundwaters. This conclusion is not cancelled by relatively large DTW distances found in some cases, meaning that some additional decrease in water quality is possible due to mass transfer of impurities between neighbouring geological provinces. Based on the results of the work, it is recommended to expand the programme of hydrogeochemical monitoring of pollution over the districts of Moscow in combination with the formation of a currently missing reliable profile of groundwater composition, in particular in relatively deep aquifers.
M. E. SEMENOV1, U. ZH. MIRZAKIMOV1, A. YU. MANAKOV1,2, A. K. SAGIDULLIN1,2, R. S. PAVELYEV1, M. A. VARFOLOMEEV1 1Kazan (Volga Region) Federal University, Kazan, Russia 2Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
Keywords: methane hydrate, gels, copolymers, promoter, gas storage
The results of studying methane hydrate formation processes using swollen gel particles synthesised from the copolymers of acrylamide and acrylic acid with varying degrees of cross-linking are presented. The effect of chemical composition of gel particles and their structural-morphological characteristics on the hydrate formation kinetics and efficiency of water conversion to methane hydrate is investigated. Experimental studies were conducted in specialised autoclave installations under strictly controlled thermobaric conditions: initial pressure at 20 °C was 9.5 MPa with subsequent temperature reduction to 1 °C to ensure thermodynamic conditions for hydrate stability. It has been established that gel particles containing predominantly acrylamide fragments exhibit low activity in initiating hydrate formation and do not contribute to the formation of significant amounts of hydrate. In contrast, particles with reduced cross-linking degree and increased content of acrylic acid functional groups demonstrate intense hydrate formation with almost no induction period. The quantitative analysis of hydrate formation products in the case of samples with a high content of acrylic acid fragments has demonstrated high efficiency of water conversion into methane hydrate reaching 42-67 %. Introduction of a kinetic promoter based on castor oil (COS-3MS) into the mixture of gel-forming agents allowed for an additional increase in the degree of water conversion to hydrate up to 58 %. Visual observations revealed a characteristic hydrate growth mechanism: the process is initiated on the surface of gel particles, and then the crystals propagate into the gel volume through diffusive and capillary transport of the aqueous phase. The obtained results convincingly demonstrate the high potential for the practical application of gel systems for intensifying hydrate formation processes and creating innovative technologies for efficient storage and transportation of natural gas in the hydrate form.
E. N. FEDOSEEVA, V. B. FEDOSEEV
Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
Keywords: lactic acid, polylactide, polycondensation in spray, size effect
The kinetics of lactic acid polycondensation in the dispersions of liquid-gas type is investigated. The dispersions were obtained by depositing drops of lactic acid spray or applying an ensemble of millimetre-sized drops from a capillary onto a glass substrate. The average droplet diameter for the fine and coarse-dispersed samples differed by more than an order of magnitude. The dynamics of changes in the amount of lactic acid in washouts from the substrate were analysed using anion chromatography. It has been confirmed that polylactide is formed during dispersion at room temperature and atmospheric pressure without the use of a catalyst. The reaction rate is directly related to the diameter of droplets in the dispersion. It has been shown that an increase in temperature from 20 to 40 °C causes an increase in lactic acid conversion by a factor of 1.5.
M. S. FUFAEVA1, V. S. OVSYANNIKOVA1, S. E. DRAGULA1, A. S. BUYAKOV2 1Institute of Petroleum Chemistry, Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia 2Institute of Strength Physics and Materials Science, Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia
Keywords: polyvinyl alcohol, potato starch, boric acid, glycerol, cryogel, elasticity, biodegradation, ecology
The influence of glycerol and boric acid on the rheological properties of aqueous solutions of polyvinyl alcohol (PVA) and starch, as well as on the elastic and thermophysical properties of cryogels prepared from them, was studied. It has been shown that all solutions exhibit non-Newtonian properties. The addition of 0.5 wt% boric acid caused an increase in the dynamic viscosity of PVA solution by a factor of 1.5-2.3, and starch solution by a factor of 0.8-1.1; the addition of 0.25 wt% boric acid with 10 wt% glycerol as a plasticiser caused a 1.6-2.4 times increase in the viscosity of PVA solution, and the viscosity of starch solution increased by a factor of 0.9-1.3. The addition of 20 wt% plasticiser (glycerol) had a maximum effect and caused an increase in the dynamic viscosity of PVA solution by a factor of 1.8-2.6, and starch solution by a factor of 1.1-1.5. It has been determined that the elastic modulus of cryogels increases with the addition of glycerol and boric acid into the polymer solution (PVA, starch or their mixture). The elastic modulus of cryogels has been determined to depend primarily on the proportion of each polymer in the mixture, and then on glycerol concentration, increasing by a factor of 2.6-12 in its presence. During destruction in water, the mass loss by compositions based on starch was 45-70 % within 20 days. For the mixed compositions with two polymers, the weight loss within 30 days varied within the range of 40-65 %. The presence of glycerol suppressed the destruction of samples with high PVA content (weight loss 24-28 %) and stimulated the decomposition of cryogels with high starch content (weight loss up to 83-87 %). Microstructural studies of films based on PVA and starch with glycerol before and after biodegradation showed the colonisation of surfaces by microbial cells, the appearance of irregularities, cracks and cavities.
N.M. SYSOEVA
V.B. Sochava Institute of Geography, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
Keywords: formal and informal institutions, evolution of institutions, spatial variability of institutions, embeddedness of economic action, interaction networks, local community
The article evaluates the potential for expanding the analysis of the territorial organization of production and settlement using an institutional approach. A counter movement by economists and sociologists toward geography as a science exploring the diversity of the environment external to institutions has been noted. In geographical studies, the institution itself rarely becomes the subject of spatial analysis; it primarily serves as an attribute of the object of study. It is demonstrated that the geographical view on institutions suggests two directions of research: the reflection of territorial characteristics in the nature and forms of certain institutions; and the spatial variability of institutions themselves, determined by the properties of the territory. The economic-geographical analysis primarily uses formal institutions, i.e., legalized norms and organizations. Informal behavioral stereotypes appear in socio-geographical works without corresponding generalizations as institutions, most often when studying rural areas. A comparison is made with the views of foreign scholars on the institutionalization of economic geography, identifying three directions for the development of the institutional analysis. The first one is the study of the evolution of the economic landscape, since institutions are characterized by inertia and maintain dependence on the previous path. Within the framework of this direction, the predisposition of local economies to innovation is considered. The second direction is the study of the embeddedness of economic action in local social structures, i.e., dependence on networks of communication with the local community. The third direction is increasing the importance of the local level in economic and geographical research, differentiating the locations where certain norms, rules, and interaction networks operate. Using the principles of evolution, embeddedness, and differentiation within the institutional approach, it is possible to develop a theoretical and methodological basis for studying the causes of various spatial processes, including population outflow from strategically important regions and the incomplete implementation of major investment projects, as well as for formulating an ideology of the territorial economic development based on endogenous resources under the conditions of an expected reduction in federal support funds.
V.N. VESELOVA, A.V. BARDASH
V.B. Sochava Institute of Geography, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
Keywords: socioeconomic development, population quality of life, social justice, regional policy, indicative analysis, monitoring
The relevance of the issue of socioeconomic development of regions has been determined from the standpoint of Russia’s national security. It is shown that systematic monitoring of the dynamics of socioeconomic processes is necessary to implement a balanced state policy aimed at reducing interregional disparities. An analysis of the country’s socioeconomic development was carried out using key indicators of the standard of living and quality of the population for 2000-2021 at the federal and regional levels. At the first stage, district types were identified based on the combination of poverty level and life expectancy. At the second stage, integral indices of the standard of living and quality of the population were calculated at two hierarchical levels as an additional characteristic. An indicative analysis method with risk zone gradation was used to analyze the socioeconomic development of federal districts and subjects of the Russian Federation. The analysis revealed a decrease in the poverty level of the population and an increase in life expectancy for the Russian Federation as a whole. However, despite positive trends, the threshold values оf these indicators were not reached, and the combination of “poverty level and life expectancy” in terms of security remained static over the period under review. A similar trend is observed in the federal districts, with the exception of the Central and Northwestern ones. The North Caucasus, Siberian (SFD) and Far Eastern (FEFD) federal districts remain in the worst situation. The following contradictions related to the standard of living in the SFD are identified: insufficient consideration of natural and climatic conditions in the leveling of regions with a low level of economic development and diverging trajectories between GRP per capita and the standard of living of the population in “strong” industrial subjects. The low quality of the population in the SFD and FEFD has persisted over a long period. Based on the analysis of indicators of the standard of living and quality of the population, it is concluded that the current situation, particularly in the SFD and FEFD, contradicts the principle of social justice and requires fundamental changes in the state’s regional policy.
O.V. EVSTROPYEVA
V.B. Sochava Institute of Geography, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
Keywords: tourism, recreational geography, institutional approach, institutional barriers, core-periphery, visa-free regime
The article presents the results of the spatial analysis of travel freedom and countries’ openness to international tourism. The relevance of the study is determined by the transformation of the international tourism space in the context of the global multi-crisis. An institutional approach has been applied, the essence of which consists in identifying and studying the institutionally determined factors of the spatial development of tourism, which are formed at the international level. The article examines the geographical space within which general principles of partnership and cooperation between countries in the field of travel organization operate. A significant factor in the spatial development of tourism is tourist formalities, which are considered in a core-periphery context. They represent the most significant institutional barriers to tourist mobility, standing in the way of international tourist flows. It has been revealed that most countries of the global economic core are characterized by a high level of freedom of movement and, at the same time, increased requirements for incoming travelers. In the periphery, many island states with tourism playing a high role in their economies stand out for their openness. The share of the population traveling around the world without a visa has remained relatively stable over a long period of time. In the countries that largely shape global politics and economy of the modern world (the USA, Great Britain, China, Russia, Germany, and France), changes in visa-free travel opportunities occur synchronously. The general trend of increasing travel freedom observed for citizens of most countries indicates an expansion of the tourism space, despite growing economic and political instability, as well as the consequences of the global tourism crisis resulting from the coronavirus pandemic.
Socioeconomic and foreign policy turbulence poses a challenge for the scientific community of developing scientifically based approaches to assessing the sustainability of regional tourism systems, their adaptive management, and creating mechanisms to increase their sustainability. Of particular interest in this context are the regions of the Siberian Federal District (SFD), which have significant, but unevenly realized, tourism potential. This study focuses on the features of response of the tourism sector of the SFD subjects to the crisis shocks of 2000-2024, identified through the analysis of the dynamics of overnight stays. The work aims not only to diagnose the levels of regional sustainability, but also to identify key factors in their ability to adapt and recover from the crisis. The study is based on the combined application of two complementary methods: a multicriteria analysis of long-term trends in the indicator of tourist overnight stays; and the identification and analysis of specific response models (V-, U-, L-, W-types) to economic crises. Using the results of the analysis, areas of consistency in the findings obtained applying both methods, as well as illusory contradictions explained when proceeding to a qualitative analysis of the dynamics were identified and interpreted. Based on the synthesis of methods, an integrated classification of the SFD regions was developed. In addition to describing the current state, the resulting typology reflects the dynamics of the regions’ adaptive potential. The research results can be used by regional government bodies to develop differentiated anti-crisis policies in the tourism sector, thereby facilitating the implementation of the national project “Tourism and Hospitality” and the state program “Tourism Development”.
The problem of atmospheric pollution in a large industrial city is considered. The relevance of using spatial modeling for identifying urban areas most susceptible to atmospheric air pollution and developing measures to improve the atmo-ecological situation is shown. The article substantiates the proposition that the degree of pollution of the ground layers of the atmosphere in an industrial city, as well as the resistance of the urban environment to air pollution, are determined by the effect of opposing processes: atmospheric pollution by emissions from transport and industrial enterprises, on the one hand, and self-purification of the atmosphere due to natural conditions and built-up area patterns, on the other. The degree of resistance of the urban environment to atmospheric pollution depends on the character of interaction between natural and anthropogenic factors, the most significant of which are topographic features, wind regime, climatic characteristics, the actual amount of pollutant emissions, and built-up area patterns. These factors are described in the created analytical models, reflecting three blocks of data: the natural ventilation potential of the territory, stable zones of actual pollution, and the aeration potential of the built-up area. Based on analytical models, a polystructural atmo-ecological model of the urban environment of Saratov was constructed, reflecting the territory’s resistance to atmospheric pollution, taking into account the natural ventilation potential of the city’s territory, the aeration potential of the existing urban development, and the formed permanent halos of atmospheric pollution. The model identifies four categories of urban areas according to the degree of resistance to atmospheric pollution (highly resistant, resistant, non-resistant, extremely non-resistant), for each of which measures are proposed to improve the atmo-ecological situation.
A.V. ANDRIANOVA1, T.P. SPITSINA2, A.V. KHILYUK2 1Institute of Computational Modeling, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, Russia 2Reshetnev Siberian State University of Science and Technology, Krasnoyarsk, Russia
Keywords: pollutants, zoobenthos, bioindication, spatial dynamics, specific combinatorial water pollution index, river regulation
The article presents the results of a comprehensive assessment of the ecological state of waters of the Yenisei River along the entire length, obtained using chemical and biological methods. Materials from Roshydromet, regional State reports on the state and protection of the environment, and the results of our own field research were used as the initial data. It was revealed that persistent pollutants in the Yenisei River include metals (ions of total iron, copper, aluminum, manganese, and zinc), petroleum products, phenols, and organic substances. The upper section of the Yenisei River is rich in biogenic elements; after the confluence with the Angara River, their concentrations significantly decrease due to both dilution and biological processes. However, while the content of organic and biogenic substances decreases, the concentrations of copper, zinc, and petroleum products increase from the middle reaches to the mouth of the river. According to the specific combinatorial water pollution index, the Yenisei water corresponds to categories ranging from “slightly polluted” (class 2) to “dirty” (class 4a). A steady trend of increasing pollution from the headwaters to the mouth of the river is observed. Communities of benthic animals, whose development in the Yenisei is not limited by high-velocity conditions, as compared to planktonic organisms, were used as bioindicators. All bioindicative parameters (13 indices and metrics) consistently demonstrated a trend of water quality deterioration from the headwaters to the lower reaches of the Yenisei, supporting the hydrochemical methods. After the confluence with the Angara River, due to a decrease in the concentrations of organic and biogenic substances, an improvement in water quality was noted according to a number of indices taking into account organisms sensitive to pollution. The reason for the water quality deterioration relative to natural conditions is the reduced self-purification capacity of the watercourse after the cascades of hydroelectric power plants and the high level of pollution from waste water of large cities. Biogenic elements and organic substance accumulate in the reservoir beds. The ecological water quality of the Yenisei River is influenced by both anthropogenic and natural factors, particularly by heterogeneous hydrological conditions and a network of large right tributaries.
A.M. PLYUSNIN, A.V. UKRAINTSEV, A.O. BURKHISANOV, R.Ts. BUDAEV
Dobretsov Geological Institute, Siberian Branch, Russian Academy of Sciences, Ulan-Ude, Russia
Keywords: sandy deposits, chemical composition of sands, sand fractionation, longshore transport, coastal abrasion, Sor Cherkalovo Bay
The article presents the results of the study of the formation patterns of the island chain separating Sor Cherkalovo Bay from Lake Baikal. The results of the study of the granulometric and chemical composition of the sands that compose the islands located in Sor Cherkalovo Bay and the Selenga River delta, as well as the coastal terraces, are reported. It is shown that during the high-water period of 1983-1994, intense abrasive destruction of the southeastern coast of Lake Baikal occurred. Based on the author’s calculation methodology, it is shown that abrasion in the area under consideration destroyed 27,6 m of coastal terraces over a 10-year period. Hundreds of thousands of tons of loose material were carried into the lake’s waters. It was revealed that abrasion-accumulation processes resulted in the separation of the sand material into fractions. Sands with a particle size greater than 0,25 mm remained on the beach at the site of coastal terrace destruction, while the finest fraction of sands, with a particle size less than 0,14 mm, was carried by waves into the lake, and particles with a particle size of 0,14-0,25 mm began to move along the shore with the current. In the area of Sor Cherkalovo Bay, under the influence of water flows from the Selenga River, the velocity of the longshore current slowed, and sand material began to accumulate as bottom deposits. During autumn storms, the resulting bottom deposits formed sand ridges and then bars due to bottom transport. Over time, fine dust and plant seeds carried by the wind from the coast of Lake Baikal transformed the sand bars into islands. The 0,14-0,25 mm sand fraction, which played a major role in the formation of the island chain under consideration, makes up a significant portion of the deposits on the coast of Lake Baikal. Its accumulation in coastal deposits is associated with aeolian winnowing of sands. The article presents satellite and UAV images of the islands. The photographs show the morphological forms of the islands associated with the movement of sands by waves and water flows from the bay into Lake Baikal. A diagram of the formation of the island chain in Sor Cherkalovo Bay is provided, indicating the direction of flows of water and suspended matter.
T.A. BORISOVA, A.N. BESHENTSEV, S.A. PETROV
Baikal Institute of Nature Management, Siberian Branch, Russian Academy of Sciences, Ulan-Ude, Russia
Keywords: digital elevation model, geomorphometric analysis, hazard, risk, hydrological data, mapping
The article presents the results of the analysis of archive materials of the long-term (1936-2015) observations of floods on the Barguzin River. A digital elevation model was created for geomorphometric analysis of the river basin relief. Automated analysis of relief indices in the Saga GIS software environment and expert interpretation of Landsat images from different periods made it possible to differentiate the basin territory into homogeneous hydrological sites characterized by similar physical and geographical parameters of flood development. An assessment of flood formation was carried out, their genesis was determined, and metric characteristics and features of passage in different parts of the basin were identified. Maps of average water levels and flooded areas were compiled. The flood zone mapping was performed in the ArcGIS software environment based on the interpretation of Landsat satellite data from different periods and a topographic base at a scale of 1:100 000. As hydrological information for obtaining absolute flood zone boundary elevations, a sample of maximum water levels was collected from long-term observation series, and calculated water levels at the cross-sections obtained from the distribution curves of annual probabilities of exceeding maximum water levels of rain floods for hydrological posts were used. The combination of layers of hydrological sites and flood zones with the layer of agricultural lands made it possible to establish the average long-term values of flooding of the territory for hydrological sites, and to determine the areas of flooded agricultural lands and settlements. A probabilistic-areal approach was used for the cartographic assessment of risk from floods. The risk calculation procedure is based on hazard indicators through a vulnerability parameter, allowing us to determine the physical risk or damage to the territory, economic facilities, and the population (in specific indicators), which forms the basis for calculating economic risk. Specific maps and an integrated risk map were compiled.
V.S. SHEINKMAN1, S.N. SEDOV2 1Earth Cryosphere Institute, Tyumen Scientific Center, Siberian Branch, Russian Academy of Sciences, Tyumen, Russia 2Institute of Geology, National Autonomous University of Mexico, Mexico City, Mexico
Keywords: paleocryogenesis, cryogenic paleosols, polygonal-wedge structures, cryopedogenic complex, Pleistocene, North-Western Siberia (MIS-2)
The article examines the features of paleocryological development of the north of Western Siberia, identified by the authors during the study of the interaction of polygonal-wedge ice (PWI) and cryopedogenesis. The paleosols of this area have been discovered and studied in detail by the authors. The article also considers the traces of the PWI south of their modern boundary, which have been little covered in the literature. It has been established that the identified paleocryogenic complexes reliably mark paleocryological events, which is especially important when their superimposing on the freezing of rocks phenomena also generated by cold, but caused by elements of the cryogenic system with a specific organization of matter, in particular, those associated with cryopedogenesis. The area between the Arctic Circle and the latitudinal course of the Ob River was explored. Here, the traces of the former PWI clearly reflect the fact that their development differed significantly from that observed in the zone of the modern PWI, which disappear south of 68 ° N. The latter grew during all the cold epochs of the Late Quaternary under conditions of syncryogenesis, influenced by the transgressive-regressive dynamics of the Arctic seas. Further south, the traces of the PWI record their epigenetic development outside the zone of this influence and only in MIS-2. Moreover, the formation of the PWI and their successor structures was closely linked to cryohydromorphic soils, about which nothing was previously known. They developed on the former basis of the seasonally thawed layer (SRL), forming a single cryopedogenic complex with the PWI and their successor structures. They played a particularly important role during the terminal phase of MIS-2, when the PWI thawed due to the onset of warming, but the host rocks remained frozen, and cryohydromorphic soils slid along the walls of the PWI, filling the space vacated by ice. This process continued until the mid-Holocene. Later, all the sediments that contained the PWI were overlain by podzols - soils on a free-draining rock matrix - recording their thawing, and at present, permafrost islands persist only in areas with poor drainage, where peatlands form.
S.V. DOLGOV, N.I. KORONKEVICH
Institute of Geography, Russian Academy of Sciences, Moscow, Russia
Keywords: Lena River basin, climate warming, air temperature, precipitation, surface and groundwater runoff
The article identifies modern features of long-term fluctuations in air temperature for a year as a whole, and for cold (October-April) and warm (May-September) seasons in the Lena River basin with a widespread occurrence of permafrost rocks. It is shown that the increase in temperature during the cold season, which began in the mid-1980s, has had virtually no effect on the river runoff. A more important factor is the increase in temperature during the warm season since the mid-1990s, which promotes a more active participation of suprapermafrost waters (perched water runoff) in the formation of the Lena River runoff. It has been found that the distribution of the average long-term annual runoff across the catchment area is largely determined by the distribution of annual precipitation (correlation coefficient R = 0,8). Long-term fluctuations in the annual river runoff are also largely caused by fluctuations in annual precipitation (R = 0,7-0,9). In recent years (2008-2022), an increase in the runoff has been observed in the middle and lower reaches of the Lena River. Near the villages of Tabaga and Kyusyur, it amounted to 17 and 5 %, respectively, compared to the average runoff for 1930-1980, according to the State Hydrological Institute. In the upper reaches, at the cross-section near the working settlement of Kachug, the runoff, on the contrary, decreased by 6 % compared to the early 1960s. An assessment of the main elements of the genetic vertical structure of the Lena River runoff is given. In recent years, the share of the surface component of the runoff in the total runoff has been 35-50 %. A significant role in the formation of the river runoff in the warm season is played by the runoff of seasonal perched water (suprapermafrost waters) and aufeis, which constitute 20-25 % of the annual total runoff. Sustained groundwater runoff, primarily interpermafrost and subpermafrost water, accounts for 20-40 %.
D.O. ANDREEVA1, L.S. LEBEDEVA2 1Saint Petersburg State University, Saint Petersburg, Russia 2Melnikov Permafrost Institute, Siberian Branch, Russian Academy of Sciences, Yakutsk, Russia
Keywords: river freezing, runoff duration, climatic factors, landscapes of Central Yakutia, small and medium-sized rivers, permafrost
An analysis of spatial variability of the runoff duration and its relationship with catchment area, river streamflow, and climatic and landscape factors was carried out for freezing rivers of Central Yakutia based on daily water discharge data from 23 operating and closed hydrological gauges. It was found that rivers in northeastern Central Yakutia are characterized by a later onset of the runoff period in spring and its earlier end, the presence of summer drying-up, and high interannual variability in the runoff duration. It was revealed that the length of the runoff period depends to a greater extent on its end date, which varies widely across the rivers of the territory, than on its onset date. One of the key factors determining the runoff duration and its cessation date is the size of the catchment, which serves as an indirect indicator of the proportion of groundwater recharge of streams. The duration of periods without runoff is significantly influenced by temperature conditions, affecting the freezing regime of soils, which prevents underground recharge of rivers, and the intensity of evaporation, reducing the moisture reserves in the catchment area, which can lead to summer drying-up and an earlier end of the runoff period. Precipitation has a weak effect on the runoff duration. It was also found that winter precipitation has a stronger impact on the annual river runoff depth than summer precipitation. An analysis of the relationship with landscape factors revealed that the prevalence of watershed-eluvial and slope deluvial-solifluction terrain types in the catchment area contributes to an increase in the runoff duration, while alas and inter-alas types reduce it.
P.S. BELYANIN1, G.S. MIRZEKHANOV2, V.V. IVANOV3 1Pacific Institute of Geography, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia 2Mining Institute, Far Eastern Branch, Russian Academy of Sciences, Khabarovsk, Russia 3Far East Geological Institute, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia
Keywords: Unya-Bom gold-bearing region, palynological analysis, radiocarbon dating, Karginsky megastadial, climatic optimum, paleovegetation
The evolution of valley ecosystems of the Bom River (middle Amur River region) has been reconstructed over several climatic cycles of the Late Pleistocene, corresponding to the marine oxygen isotope stage (MIS) 3. The results of the spore-pollen analysis of peat and loam samples from a section of the first floodplain terrace of the Bom River, supported by radiocarbon dating of wood remains and peat, revealed evidence of repeated and significant changes in valley vegetation during climatic fluctuations of the first half of MIS 3. It was found that the warming that started at the beginning of MIS 3 caused the development of spruce-birch forests with Scots pine and alder in the valley. It has been revealed that, apparently, the forest-tundra plant formations, dominated by alder shrubs, shrub and arborescent birches, alder, and larch, which predominated during the preceding, colder era, have shifted higher up the slopes. During the climatic optimum of MIS 3, tree vegetation in the Bom River valley became even more widespread. The main ecosystems of the lower slopes were represented by spruce-small-leaved forests with Scots pine, as well as broad-leaved species such as elm, Mongolian oak and hazel. However, in the swampy areas of the valley, larch sparse forests and sphagnum bogs with dwarf birch and shrubby alder persisted. The process of sedimentation of loams and peat rich in pollen and spores was interrupted during the formation of a thick (7,2 m) layer of boulders and rubble. Significant changes in the taxonomic composition of the palynospectra and the complex lithological structure of the studied section, including transitions from alluvial and biogenic sediments to coarse-grained deposits, indicate significant changes in the natural environment in the Bom River valley during the Late Quaternary.
S.I. VIOLIN1, K.V. GRIGORICHEV1, G.B. DUGAROVA2, N.V. EMELIANOVA1,2, Yu.A. KIREEVA1, K.N. KOMLEVA1, A.M. NESTERENKO1, V.A. RUDNEVA1, K.S. TSZIAN1 1Federal Research Center “A.E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences”, Irkutsk, Russia 2V.B. Sochava Institute of Geography, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
Keywords: master plan, urban development, urban planning, development strategy, Federal Chemistry Center, single-industry city
The article considers the concept of a “master plan”, concluding that the development of master plans is a modern approach to integrated territorial development, but there are significant gaps in their theoretical justification and insufficient experience of practical implementation. At the same time, master planning has significant potential and can become an important component of the strategic and urban planning system. It is noted that more than 60 master plans for cities and urban agglomerations have already been developed in the Russian Federation; however, the issue of their development has not yet been legally regulated. It has been revealed that there is no consensus among experts regarding the place that a master plan should occupy in the system of strategic documents for territorial development. The aim of the study is to present the main results of a comprehensive analysis of the development of the city of Usolye-Sibirskoye as the first stage of preparing a master plan for this municipality. The article also highlights the city’s competitive advantages, prospects, and key constraints to its development. The following aspects are identified as the main advantages: a favorable economic and geographical location, the presence of its own natural resource base, persisting industrial potential, the presence of a preferential regime for carrying out economic activity, a developed small and medium-sized business sector, and a high provision of well-appointed housing stock. It is emphasized that the city’s main prospects are currently associated with the implementation of large investment projects, the elimination of accumulated environmental damage, and the creation of the Federal Chemistry Center. The most significant restraining factors identified are unfavorable demographic trends, low living standards and quality of life of the population, high level of deterioration and insufficient development of engineering and public utility infrastructure, unfavorable environmental situation and low provision of own budget revenues. It is noted that additional research is needed to assess the current and projected environmental situation, as well as the reasons for the high level of unemployment in the city’s economy and its structure.
A.N. SALUGIN
Federal Scientific Center for Agroecology, Integrated Land Reclamation and Protective Afforestation, Russian Academy of Sciences, Volgograd, Russia
Keywords: mathematical modeling, differential equations, Markov chains, stability, destabilization parameter, autonomous pulse processes
The article presents methods of mathematical modeling in the study of the dynamics of phytocenoses of soil-plant systems in arid zones of the south of Russia. The models are developed on the basis of continuous and discrete formalisms. The results obtained in the form of analytical expressions in continuous models were used to identify the conditions for the existence of a stable state of pasture ecosystems by applying the destabilization parameter. Quantitative relationships between the permissible pasture load and the calculated destabilization parameter obtained from Markov chains were determined. The conditions for the stable functioning of pastures are discussed, demonstrating the capabilities of continuous models in the form of systems of ordinary differential equations and discrete ones: Markov chains and autonomous pulse processes. Under anthropogenic loads on pastures, Markov chains adequately reflect the nonlinear dynamics of pasture ecosystems and predict their final steady state. This state serves as the starting point for determining the destabilization parameter, which determines the degree of ecosystem deviation from equilibrium. It is shown that homogeneous Markov chains can be used to generate short-term forecasts and manage pasture forage reserves. Using autonomous pulse processes, a model of the dynamics of phytocenoses of natural pastures was developed. Computational experiments were conducted to determine the optimal model parameters corresponding to the steady-state regime and optimal pasture exploitation. The formalism of autonomous pulse processes was used to study the dynamics of interactions between pasture phytocenoses and to determine the optimal parameters of the binary interaction matrix when solving problems of pasture bioresource management. Mathematical modeling as a method for studying the dynamics of soil-plant ecosystems in the form of natural pastures is presented as one of the main research methods in the ecology of soil ecosystems.
A.B. GLEBOVA, I.S. SERGEEV, A.S. KAPKINA, E.M. PAUTOVA
Institute of Earth Sciences, Saint Petersburg State University, Saint Petersburg, Russia
Keywords: landscape, archaeological sites, geoinformation systems, digital elevation model, analysis of variance
The article presents the results of identifying landscape patterns in the distribution of archaeological sites in Southwestern Tuva and constructing a predictive model of the locations of as-yet-unexplored objects based on a neural network. The analysis was carried out using geoinformation systems and a machine learning algorithm. For this purpose, a database of archaeological sites in Southwestern Tuva was compiled based on literary sources and the authors’ field research. Using a digital elevation model and available archaeological data, a geoinformation analysis was carried out and distribution diagrams for archaeological sites were created based on nine landscape features: absolute height, slope inclination, slope aspect, position relative to watercourses, height above the waterline of a nearby watercourse, solar radiation intensity for December and June, visibility of mountain peaks, and distance from mountain peaks. Based on the analysis of variance for known archaeological sites, a diagram of the importance of landscape features was constructed. The distance from the watercourse and the height above the waterline of the nearby watercourse played the greatest role in choosing the locations for religious structures. According to the resulting predictive model, religious sites can be found primarily along the western periphery of the Khemchik depression, along the river valleys flowing toward this depression, and along the river valleys in the southwest of the study area. The accuracy of the predictive model was approximately 85 %. The obtained data make it possible to assess the role of landscape features in the distribution of archaeological sites and provide an opportunity to search for new archaeological sites.
The article presents the results of the study of the coevolution processes of tourism and economy of the northern territories of Canada. The author used system analysis tools and traditional methods of socio-economic geography (zoning and regionalization) adapted to the study of the coevolution of tourism and economy of the northern territories as a methodological basis. A retrospective analysis of the coevolution of tourism and economy of the northern territories of Canada provides the basis for identifying three stages, namely: from 1960 to the 1970s; from the 1970s to the late 1990s; and from 2000 to the present. The stages differ from each other not only in the scale and structure of tourism activity, but also in the nature of its interaction with the economy of the northern territories and the system of institutions of economic development. It has been revealed that the coevolution of tourism and economy results in changes in the trends and forms of spatial organization of the tourism industry, on the one hand, and spatial economic systems, on the other. A spatial approach to studying the coevolution of tourism and economy of the northern territories of Canada makes it possible to uncover the geographical essence of phenomena and processes, their spatial organization, and changes over time, which is associated with the highly dynamic nature of the boundaries of tourist regions, due to the cyclicity of natural processes and the non-linear nature of evolution of tourist regions. Based on the analysis of Canadian regionalization practices, we identified a network of 16 tourist regions of the northern territories and proposed a typology of tourist regions of the northern territories: monocentric, linear-nodal, and network ones. Potential areas for transferring Canadian experience in the spheres of organizing scientific research and regulating tourism activities, taking into account the specific features of the Russian North, have been identified.
13 июня 2026 г. исполняется 100 лет со дня рождения выдающегося географа-климатолога, медицинского географа Владимира Ивановича Русанова, участника Великой Отечественной войны.
