Heterogeneity of P-T conditions of metamorphism reflects complex evolutionary history of the Yenisei Ridge and is most pronounced in zones of concentrated deformations (shear zones). The aim of the study was to determine P-T conditions of metamorphism of the Tatar-Ishimba shear zone based on petrography, petrochemistry of rock-forming minerals, geothermobarometry and Ar-Ar geochronology. The study revealed 3 metamorphic assemblages with corresponding P-T stages (530-560ºС/4.8-5.0 kbar; 590-620ºС/6.5-6.7 kbar; 450-550°С, 5-6 kbar). The first 2 stages correspond to the process of crustal thickening due to block collisions. The third stage corresponds to the retrograde stage. Heterogeneity of its manifestation is associated with strike-slip displacements along the Borzetsovskaya group of faults. The age of peak metamorphism is 822 Ma and corresponds to post-Grenville orogenic events.
The source of information for the article was the atlas “Virtual Population of Russia” (2017), which accumulates open personal data on users of the VKontakte social network, their locations and preferred directions of communication. The methodological tools of graph analysis are used to identify patterns of network interactions of residents of three obviously different macro-regions of Russia – South, Urals-Volga region and Far East. The substantive interpretation of graphic images is based on the theoretical provisions of social topology, the analytical apparatus of which, unlike social geography, assumes a relational approach to understanding the category of space and is based on positional principles. The concept of “social space”, widely used in human geography, is treated in the article as a material-semiotic environment with physical (Euclidean), social (unequal positions in systems of relations) and symbolic (cognitive categories and mental constructs) metrics. Geographical maps are compared with their topological analogs, spatial features of the established network patterns are described, and their common and distinctive features are identified. The authors adhere to the distinction proposed by M. Castells’ distinction between “space of places” as a space of physical proximity and neighborhood and “space of flows” referring to network structures, hierarchies of connections and positions. Trying to understand what the substantive rather than technical novelty of social network analysis is for human geography the authors conclude that it adds a moving spatial component to the study of the “fixed” realities of the territorial organization of social life. As a discipline aimed at studying the laws of connectedness, social topology provides theoretical and methodological tools for tracing continuous changes in the space of people’s life activities under the influence of transformations of the social world (the so-called fluid modernity) and allows for empirical verification of qualitative observations and intuitions.
The purpose of the article is to substantiate the attribution to seismogenic structures (seismites) of numerous sedimentation deformations in inter-salt dolomite-anhydrite interlayers in the Lower Cambrian salt-bearing strata of the Angar-Lena steps of the East Siberian platform. А comparison of deformations, studied in the core (plicative, disjunctative and dislocation structures) with similar ones described in the literature and interpreted as seismogenic, is carried out as a methodological approach. The main result of the work is the identification of sediment structures of paleoseismogenic origin. Since it is known from the analysis of literary data that in non-consolidated or poorly-consolidated sediment deformation can appear both with the participation of seismicity and without it, due to other factors - the excitement of water, gravity, etc., all types of deformations were divided into three groups by origin. Non-seismogenic, double origin and probably seismogenic (seismites). At the same time, there are dislocations in the studied thickness, the seismic origin of which with a very high degree of probability took place. These include ditches that violate the smooth surface of the bottom of salt lagoons and ruptures in the monolithic sediment (large separation cracks with signs of instant formation), dissecting sedimentary strata at some depth. The sources of Paleoseismicity can be in the surrounding Siberian platform mobile tectonics zones, which have not yet completed consolidation in the early Cambrian. In the southeast, these are Baikalids, in the southwest - the Sayan Caledonids with the main Sayan fault.
The article studies geographical images of the federal subjects of Western Siberia, which have formed in the public consciousness of the population of Russia. The analysis of geographical images as group mental models of territories (which reflect both real and fictional, stereotypical and fantasy characteristics of them) has important practical significance, since they form the general everyday idea of this space and attitude to it. At the same time, administrative-managerial and personal decisions based on these mental representations are made in real space. The article reflects the results of a sociological study in which 685 people from 29 regions of Russia participated as respondents. Based on their surveys, the analyzed database of geographical images of administrative entities, the West Siberian economic area was formed. In the course of the study, not only the main geographical images of each of the nine subjects of the Russian Federation studied were identified, but also erroneous ideas, stereotypical and even mythological images present in the popular consciousness were identified. Also, in the course of the work, it was possible to identify patterns of differentiation of the mental space of Western Siberia, differences in information capacity and reliability of geographical images of different regions. The factors and mechanisms of forming people’s ideas about different territories and the geographical picture of the world are determined. In particular, the phenomena of “privatization of images” and “inertia of image change” are characterized. Based on the genesis of geographical images, their classification is carried out with the allocation of six main types of geographical images. For each region studied, an analysis of the ratio of images of different types was carried out, which was graphically reflected using spider diagrams, the configurations of which quite clearly reflect the degree of formation and typological orientation of the mental space of each region. The formation, images, and their reliability were assessed, which showed significant regional differences. Analysis of the level of positivity and compliance with the goals of regional development of geographical images, which provides incentives for improving the media policy of the respective regions.
This study addresses the issue of existing spatial data on regional soil-geochemical background and the limitations of its application in applied environmental research. In the context of monitoring and engineering-ecological surveys, the background level of heavy metals in soils is considered as the sum of their natural content and inputs due to long-range transport. The territories that correspond to this idea of the background are nature reserves. We considered abandoned lands with postagronenic soils as an alternative option for areas with heavy metal content close to the natural level. A literature review of data on the regional background of the Leningrad Region and some areas of the North-West of the European Russia revealed a significant spread of heavy metal values in soils even of the same type. This spread is due to differences in the lithology and landscape. Therefore, comparison of the content of heavy metals in soils of impact zones or areas of engineering and environmental surveys is possible only with reference soils formed in similar lithological and landscape conditions. We determined the content of total and mobile forms of heavy metals in the soils of the Shalovo-Perechitsky nature reserve and postagrogenic soils in the area bordering the Cheremenetsky nature reserve. The nature reserves are located in Luzhsky district of the Leningrad region. The studied soils are Entic Podzols (Arenic, Geoabruptic), Entic Podzols (Arenic, Geoabruptic, Aric) and Albic Podzols (Arenic, Geoabruptic, Aric). All these soils are formed on bipartite sediments. These types of soils are widespread within the Pskov soil district and the Leningrad region. The patterns of distribution of total and mobile forms of heavy metals in the profile of Al-Fe-humus soils on fluvioglacial sands and sandy loams underlain by moraine and lacustrine-glacial clays have been revealed. A comparison of the content of heavy metals with existing standards and generalized data for the North-West European Russia was made. The obtained results can be used as a background in monitoring studies and engineering and environmental surveys. The issue of forming a regionally specific background for the most common soil-rock-relief combinations remains relevant.
