Geoèkologiâ

The use of the orotectonic method made it possible to detail significantly the previously proposed schemes of neotectonic zoning of the Eastern segment of the Greater Caucasus megavault. In the Russian part of the segment, the zones of the North-Eastern and Central uplifts are traced. Within the North-Eastern zone, Western, Eastern and Southern subzones are distinguished, differing in their structure and orientation of the main structures. Block structures predominate in the Western and Southern subzones, and folded ones in the Eastern subzones. Among the anticlinal folds, there are folds with eroded arches, as well as folds that are partially preserved. The zone of the central uplifts includes the subzones of the side and main ridges, separated by the subzone of the axial troughs. The trough subzone crosses the entire Eastern segment of the megavault and includes the Northwestern group of differently oriented grabens and the eastern Bezhtino-Samur suture-depression zone with longitudinal grabens. This zone and its subzones are limited by the largest faults and reverse faults. Most regional and local structures are separated by active faults, which may be dangerous for the stability of engineering structures. The obtained original data, which is not available in standard materials on geological surveying for a given area, is useful for construction design and geoecology.

The article based on the methodology of interdisciplinary research solves the problems of retrospective analysis of the resource potential dynamics of geosystem components in the natural reserve located within the boundaries of the largest megacity of Eurasia to diversify the resource potential of the ecological-educational function of its territory. The unique experience of stable functioning of recreational territory is systematized synchronously with socio-economic development of Moscow urban industrial agglomeration based on complex studies. Additionally, some parts of its territory were studied in order to actualize scientific and educational tasks of higher school. The study is based on systematic approach to clarify the ecological state of the components of the environment. Local areas of different vector dynamics of geosystems of different genesis were identified. The role of natural and natural-anthropogenic factors (geological-geomorphological, ecological-geochemical, geodynamic, geophysical, anthropogenic, socio-economic) in the formation of geo-ecological features of the recreational potential of the conservation area of the urban environment is differentiated. The dynamics of the resource potential of the recreational cluster of the megacity occurs synchronously with the growth of the urban population of the urban-industrial complex and depends on the totality of socio-economic, cultural-historical, geo-ecological conditions and the synergetic vector of their interaction. The interdisciplinary approach based on the processing of databases, field observations and laboratory studies allowed the authors to improve the methodology of setting scientific and educational tasks within the framework of the implementation of the ecological-educational function of protected areas. Specially protected natural territories of megacity contribute significantly to the achievement of goals of stable urban development, preservation of biodiversity of territories and recreation areas, predetermining the creation of a comfortable environment for the inhabitants of large cities, contributing to the minimization of health risks for different gender groups of the population.

The geochemical features of mercury migration in the environment of a city located in the permafrost zone are considered. The average Hg content in suspended matter in the surface atmosphere ranges from 0.11–0.22 in winter to 13–14 mg/t in summer. The total annual intake of Hg from explosives from the atmosphere to the surface is estimated at 11 μg/m²/year, 99% of which occurs in the warm season. Analysis of lithochemical surveys in the city showed that the average Hg content in urban soils varies within the range of 6–22 mg/t. The presence of a seasonally thawed layer, frozen and permafrost rocks determines the binary structure of the cultural layer and the contrasting distribution of Hg in soils. It has been established that the abnormal Hg concentrations in the soils of cultural layer are mainly due to the intake of pollutants in the solid and liquid phases and, to a lesser extent, by the intake from the atmosphere and the chemical composition of the alluvial substrate. The occurrence of Hg anomalies in soils of a cultural layer older than 100 years is determined primarily by the biophilic accumulation of Hg in organic objects of vital activity of domestic animals and humans. Maximum Hg contents of up to 2000–5000 mg/t are observed in seasonally thawed soils in the depth range of 1–4 m, with a technogenic impact lasting more than 150 years. In the urban areas with less lasting technogenic impact, Hg is also fixed in seasonally thawed and frozen soils, with an average concentration of 50–120 mg/t, or forms low-contrast anomalies only in the soil-vegetation layer.

The article discusses the application of FreezeThaw75 module, developed by one of the authors to calculate heat and mass transfer taking into account water–ice and ice–water–water phase transitions. Numerical simulations are compared with the analytical solution and other software codes. The module was tested at one of the injection sites in Daldino-Alakitskii district of Yakutia. FreezeThaw75 module was developed in relation to Feflow v7.4–7.5 model environment. The module was tested on a model of brine injection into frozen rocks. The model simultaneously takes into account the movement of groundwater flow, heat and mass transfer and phase transitions. A feature of the calculations in the developed model is the consideration of large injected volumes of highly mineralized brines.It influences the degradation of permafrost and takes into account the cryohydrogeological conditions of the site. Brines are injected into permafrost rocks with a high absorption capacity especially in areas confined to zones of tectonic disturbances. The developed module can adjust the predicted potential of the operated injection sites. It can also act as an additional element of control over the injection process and the formation of an artificial aquifer in the permafrost rocks.

The article presents the results on laboratory tests of a short-baseline digital deformometer (SDC), developed to study deformation processes on pipelines and units of engineering structures, with the changes made to its design and electronic part, as well as the results of testing a new design of the test bench. The presented results show the effectiveness and accuracy of the new testing methodology, which makes it possible to increase the reliability of the results obtained.