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The behavior of calcite at pressures up to 1000 GPa is simulated taking into account the high-pressure phase transition. The shock-wave loading of calcite was calculated using a thermodynamically equilibrium model. A few-parameter equation of state of the Mie--Gruneisen type is used to describe the behavior of condensed phases. In the phase-transition region, the components of the sample under study are considered as a mixture of low- and high-pressure phases. The shock Hugoniots of single and double compression are constructed in the pressure range from 1 to 1000 GPa, and the heat capacity along the normal isobar, entropy as a function of temperature, and the thermodynamic potential along the shock Hugoniots were calculated. The simulation results were verified against experimental data and available calculation results

The seismic observations of dumps at the Mikhailovsky GOK open pit mine are carried out during mass blasting. The curves of the acceleration amplitude and velocity of vibrations in a blast-induced seismic wave and the reduced distance are plotted. The dynamic stability of the overburden dumps is estimated. It is shown that at certain reduced distances, multiple seismic effects of mass blasting can lead to the loss of the dynamic stability of the dumps. The results are applicable in mass blasting design and in location and parametrization of overburden dumps.

The mining drawing schedule is related to the safety, environment and ground pressure control of mine production, and is of great significance for controlling the economic indicators of mine operation in block cave mining. The mixed integer programming(MIP) method has been proved to be very effective in solving the medium- to long-term drawing sequence optimization problem in mines. The amount of ore, three kinds of the draw points priority order with diamond undercutting mode, and the logical relationship are considered as constraints based on the value model of ore-rock mixing. The maximizing net present value of the mining operation is used as objective function. Application and analysis of the model is solved using CPLEX, MATLAB, and YALMIP for a specific Chinese copper mine using 770 drawpoints over 7-year (28-quarter) periods.

The article studies a new collector represented by a dithiazine-class complexing agent-1-carboxy-2-perhydro-(1,3,5-dithiazine)-5-il ethane (CPDE). The study of the physicochemical properties of the agent and its interaction with the mineral surfaces of galena and sphalerite used the methods of IR and UV spectroscopy, as well as measurements of wetting angle and free energy. It is found that the agent makes the surface of galena hydrophobic and the surface of sphalerite hydrophilic. The comparative flotation results indicate that the CPDE possesses higher selectivity as compared with the PBX agent and ensures selective separation of galena and sphalerite during flotation.

The Donbas region has accumulated hundreds of coal waste dumps, and not less than one third of them are self-heating. With a view to substantiating parameters of a system for temperature monitoring of self-heating coal waste dumps, the temperature field dynamics was analyzed using model fills. It is found that a fill of unoxidized waste rocks possesses more pronounced properties of a heat accumulator than a fill of oxidized waste rocks. The rate of average temperature variation and the temperature field nonuniformity of the model fills under influence of internal and/or external sources of heat emission are governed by both grain-size composition and thermal destruction of waste rocks. The features of temperature stratification of heated model fills are conditioned by their genetic structure and by spatial location of heat sources. The research findings are useful for determination of sampling times for heat meters, adjustment of their positions in subsurface zones of self-heating waste dumps, as well as for interpretation of temperature monitoring data of such man-made formations.

The deepest-level underground structures of various purpose are mines, tunnels, hydropower stations and underground research laboratories. The authors describe a possible classification of rockbursts by their initiation mechanism: ahead of a mined-out space, in a pillar, nearby a fault. The authors review the common applied systems of rockburst hazard prediction and select continuous measurement systems which produce data suitable for machine processing. The geodynamic situation prediction at a mineral deposit using artificial neural networks is described. The comparative test of machine learning methods for the analysis of geodynamic phenomena is carried out. The structure of artificial neural networks for the prediction of geodynamic phenomena and stability of underground openings is described. The seismic events in the Sheregesh Mine are selected for the analysis. It is found that different models accurately determine clusters of seismic events. k-means clustering produces the best results (97.92%).

The article presents an assessment algorithm for vegetation in areas of coal dust pollution. Two problems are solved: delineation of a dust pollution area by the Enhanced Coal Dust Index with data clustering; calculation of vegetation indexes in selected clusters for the vegetation analysis. Clustering used the Hill Climbing algorithm. The source data were Sentinel-2 imagery obtained during the spring and summer seasons. The algorithm was tested as a case-study of the mining area of the Urgal Coal Mine in the Khabarovsk Krai. The test data for a period one year long show the vegetation damage on drawing nearer the test mine area.

The article describes a strategy for quantitative analysis of mono- and polysystem organization of multi-level geospaces with the construction of a series of empirical models of inter-component and inter-complex connections. As a methodological basis, a provision on structural levels of natural-territorial organization is proposed, based on a conceptual cybernetic model of a natural complex as a hierarchical control system. Using the model, a system of conjugation of different-level characteristics of natural components with a taxonomic rank of geographic spaces (from a geographic sector and natural zone to a landscape facies and biogeocenosis) was constructed. Based on the spatio-temporal relationships of inter-component and inter-complex connections, a hypothetical cycle of the trajectory of changes in the states of geospaces in their spontaneous development and under anthropogenic disturbances is described. The assessment of the dynamics of geospaces was carried out through operations with their ecological niches in the zones of their contact and intersection, i.e. in trigger zones. The stability of different-order geospaces to external disturbances is proposed to be expressed by measures of significance of their representation of the entire variety of input environmental factors. These measures serve as generalized criteria of homeostatic reserves of natural complexes. They are calculated on the basis of matrices and digraphs of their inclusion relations for a particular set of system-forming factors using the Shannon information function. Using the example of the southern taiga of the Volga basin, an example of calculating one of these measures in relation to a change in the average July temperature is given.

The relevance and necessity of a global approach to natural disaster risk assessment are determined. In recent years, it has become increasingly obvious to society, scientists, management structures, businesses, and politicians. It has been shown that various dangerous natural (earthquakes, tsunamis, hurricanes, floods) and anthropogenic (industrial accidents, pollution and degradation of landscapes, depletion of natural resources) processes constantly threaten millions of people around the world. These processes differ greatly from each other, but the assets exposed to their impact are basically the same: population, economy, territories, ecosystems, infrastructure, and the environment. It is concluded that the results of the impact on them should be considered as a dynamic process, examples of which are rapid urbanization, rural depopulation, changes associated with the actual evolution of settlements themselves, declining quality of life, etc. In this aspect, the main task for researchers is to find innovative, as simple and effective methods as possible for collecting, organizing, storing and transmitting data on such impacts, taking into account their inherent spatio-temporal dynamics. The objective of this article is to analyze the challenges of implementing an impact model on a global scale, suitable for various natural hazards within a dynamic and scalable framework, based on the method of estimating the global risk index for countries of the world. A roadmap is being developed for the use of the global impact model that will continually evolve over time through input and updating of data, including consideration of uncertainties. It is established that such a model will form the basis for a global assessment of vulnerability and risks from natural disasters, providing reliable standardized information on assets and entities exposed to various natural hazards.

The article is concerned with the development of an institutional approach in recreational-geographical research. Its essence lies in the study of patterns of associated territorial and institutional development of tourism and recreational activities, which form the most important institution of our time - a system of specific norms and rules, as well as specialized organizations intended to meet people’s needs for rest and recovery, streamline and regulate the tourism industry, as well as to use natural and cultural values in recreational aims. Within the framework of recreational-geographical research, the institution under study is considered as an object of geographical research that has relatively stable ties with specific territories and influences their nature, society and economy. To develop a logical research scheme, a methodological approach was used based on identifying common elements and points of connection between the models proposed by recreational geography and sociology. It is based on systemic, institutional and spatial concepts of tourism and recreational activities. The core of the scheme is tourist territories characterized by the originality of the institutional environment. The associated territorial institutional and recreational systems are an analytical tool. It makes it possible to organize territorial, institutional, spatial and other types of interactions that arise as a result of tourist exchange, institutional adaptation of the territory to tourism and recreation, contributing to the formation of an integral tourism and recreational space. It is shown that institutional conditions formed at various hierarchical levels determine both opportunities and limitations for the development of tourist territories, act as a significant factor in the territorial organization of tourism and recreational activities. An integral part of the recreational environment is the institutional environment, i.e. a territorially confined set of institutional conditions, a sphere of interaction of various institutions. Institutions operating within the territory can interact regarding the organization of recreation and tourism and form territorial institutional systems. An example of the application of the institutional approach is the Baikal natural territory, which is characterized by a complex combination of current environmental restrictions and, at the same time, a special attractiveness for tourists. Under such conditions, the lake shore has become an institutional epicenter of ecological and economic problems and is of particular interest as an object of institutional recreational-geographical research.