Stability of the bedrock of castle building for geotourism purposes

The geological structure of the Slovak Republic is very complex and varied. This fact in the course of centuries has had an impact on the castle buildings built here. The subsoil of these structures has different petrographic composition, tectonic disturbances and other geological complexities that threaten the stability of these structures and endanger the objects in their surroundings. In recent years, these structures have begun to receive deserved attention. In the past, the problems of severely disturbed blocks in the subsoil were mainly addressed and had to be rehabilitated for these reasons. These were mainly buildings whose subsoil is built with carbonate rocks. A perfect example of a long-term solution to these complex problems is also the Strecno Castle. A lot of effort and money has already been devoted to solving the stability of the bedrock, which also adversely affects the stability of the castle. However, the extensive set of works that have been carried out here over a long period of time have not brought a complete solution to the problems that occur here. For this reason, continuous work is being carried out here under the guidance of experts to eliminate the effects of erosion of the bedrock in particular. In the present work, the activities and measures that have been implemented here in stages up to the present are briefly described chronologically.

INFLUENCE OF TECTONIC DISTURBANCES OF COAL LAYER ON HIS GAS DYNAMIC STATE

Problem Statement and Purpose. At one of the coal mines of the Donetsk basin, there was a sudden release of coal and gas. The peculiarity of this case is that the accident happened in the place of the alleged development of a geological disturbance, but without any visible signs of this. Inspection of the ejection site and adjacent horizons made it possible to conclude that the emergency site is located in the place of the plicative disturbance development. Thus, it is necessary to study in more detail the influence of disturbed zones hidden nature on the gas-dynamic state of the reservoir, as well as to develop and implement methods for determining such zones. Data & Methods. To achieve this goal, a new method was tested, based on the property of structureless substances to form crystal-like units. This phenomenon has been studied for decades; therefore, such new formations have long been given the name quasicrystals. It was noted that the increase in the concentration of such forms is associated with the presence of geological disturbances. Consequently, the increase in quasicrystals in the rock is an indicator of its disturbance due to the influence of tectonic pressure. Thus, in order to test the technique and reveal the hidden geological disturbance of the coal seam, coal samples were taken, microstructural features were studied, and the strength of the coal seam was measured at 56 points. Result. As a result the values of the concentration of quasicrystals, data on the strength of the formation were obtained, a schematic map of the development of the disturbance in this area was built, its contours were determined, the center of the disturbed zone was identified and the role of such disturbances in the outburst hazard of the formation was substantiated. It has been established that geological disturbances, even of plicative nature, have a high degree of fracturing. Such pores and cracks in coal reduce the strength properties and are able to concentrate sufficient volumes of gas for manifestation of GDP.

Free gas content of the rocks of the silvinite and silvinite-carnallite zones at the Upper Kama Districts

The results of the mine and the laboratory studies of the free gas content of the sylvinite and sylvinite-carnallite zones of the Upper Kama districts are presented. In the process of the experimental studies, the quantitative characteristics of the free gas content were obtained for sylvinite, carnallite and rock salt layers. In the process of the laboratory studies by the gas chromatography of the natural gas samples, the component composition of the free gases was assessed. Based on the geological structure analysis and the gas content study, the assessment of the composition, the volume, the location and the intensity of the natural gases release is given. Based on the experimental studies results of the free gas content, and an analysis of the locations, the volume and the intensity of the gas emissions, the probable places of the free gases accumulation are installed. The main which are the anticlinal folds inflection the rupture and the crushing, the fractures, the tectonic disturbances, the transition of the sylvinites into the carnallite and the composition changes of the layers.

SEISMIC MICRO ZONING OF THE TERRITORY OF ALMATY ON A NEW METHODOLOGICAL BASIS

In connection with the reform of regulatory framework for construction sector of the Republic of Kazakhstan, the development of seismic zoning maps poses an urgent problem. The article presents a set of seismic microzoning maps of Almaty, developed on a new methodological basis for Kazakhstan, and provides explanatory materials on the development, understanding and use. Calculation of background seismic hazard was carried out in accordance with the basic provisions of Eurocode 8. Seismic microzoning included the implementation of two main tasks - the assessment of background seismicity and taking into account influence of soil conditions. Based on the analysis results, a set of maps have been arranged. When taking into account the influence of engineering and geological conditions, Russian and Kazakh works were used. The main maps ready for use in regulatory documents are provided. Analysis of capacities of the sediments of same age in different blocks made it possible to understand the dynamics of tectonic regime of the city territory. In the process of neotectonic activation, almost all previously existing tectonic disturbances were improved. In the contemporary relief of the urban area, most faults are not expressed.

Influence of water content on seismic activity of rocks mass in apatite mining in Khibiny

The authors analyze connection between the rock mass water content due to surface water (precipitation, snow melting and water bodies) and rock bursts in mines. The seismological monitoring performed from 2001 at the surroundings of the Apatite Circus and Rasvumchorr Plateau apatite deposits identified fluctuation of the general seismic background from year to year and seasonably. For these deposits, increased water content of rocks is seen as a natural trigger for rock mass seismicity during intensive rains and snow melting. The 15 year-long seismic monitoring of the apatite deposits under study has revealed regularity in a seasonal growth of seismicity during snow melting and precipitations, mainly in spring months. Particularities of geodynamical event occurrence allow a conclusion on the ultimately stress state of the upper earth’s crust in whole in the deposits’ vicinities. Reactivation of tectonic disturbances and weakened rock mass zones occurring due to relief of normal compression during infiltration can be a potential principal mechanism of seismic activation of the rock mass during the increased water content periods. The origin of the events observed is linked with the dynamic release of ultimate rock mass stresses when geomechanical conditions change under the action of hydrostatic pressure on tectonically disturbed zones. The authors make a conclusion on necessity to apply the revealed regularities of impact of natural factors on rockburst hazard when planning mining operations and performing geomechanical monitoring.

APPLICATION OF SEISMOTOMOGRAPHY METHODS FOR SOLVING VARIOUS PROBLEMS IN THE MINING AND GEOLOGICAL DIRECTION

The Karaganda coal basin is characterized by a complex structure. The presence of geological inconsistencies such as tectonic disturbances, washouts, variable reservoir hypsometry, etc. makes it difficult to conduct underground mining operations. Currently, in the world practice, mine seismic exploration is widely used for the purpose of studying the geological structure and solving various mining problems. Safe and productive operation of treatment faces in underground coal mining requires a timely and reliable forecast of the mining and geological conditions of the structure and condition of the coal-bearing mass from the mine workings. The most accurate and reliable picture of the tectonic structure of the Carboniferous massif can be obtained using methods of mine seismic exploration to study the geological structure and conditions of the coal bed and host rocks. The main goal of implementing modern methods of mine seismic exploration was to conduct mathematical modeling to assess the possibility of identifying tectonic disturbances with an offset amplitude of the order of magnitude and higher than the reservoir capacity using various methods of underground seismic exploration - the seismic transmission method (STM) and the reflected wave method (RWM). For this purpose, physical models of sections of the Carboniferous massif were developed, including a geometric description of geological structures, the distribution of rock densities, velocities, wave propagation and their influence on compression, and the shift of the mountain range. One of the models corresponded to a section of the formation without geological disturbances, and the second one - to a section with tectonic disturbances with displacement amplitudes from 5 to 15 m. The results obtained can be used in the development of modern effective methods for predicting the state of the mountain range in complex mining and geological conditions of both the Karaganda coal basin and other coal basins with a complex geological structure. Initially, seismic surveys were performed using the method of reflected waves using the common depth point method. However, the problem of obtaining an objective image of the geological environment is still relevant, due to the peculiarities of elastic wave excitation in mine conditions (features of the generated wave field, patterns of its propagation, the direction of the source). The method of mine seismic survey based on channel and boundary waves registration was developed and applied. This method allows obtaining a detailed geological and geophysical model of the field site. Due to the processing of both types of waves, the resolution of the method is increased to obtain information about both the coal bed and the host rocks, and, in particular, the state of the roof of the formation. The method of measurements in mine conditions is presented, the results of testing the method of performing field work in mine conditions are shown, and seismic characteristics with high contrast and clear traceability of reflecting boundaries are obtained.

PECULIARITIES OF MODERN GAS MIGRATION IN THE COAL COAL-ROCK MASSIFS OF THE DONETS BASIN

Purpose. Investigate the change in indicators of qualitative and quantitative gas composition in coal massifs,when the state of the coal rock massif changes, including in gas-dynamic situations. Methodology. The paper uses traditional structural-geological methods, generalization methods and developed and patented by the authors of the method for determining the gas state of coal massifs on the basis of gas chromatography. Results. The change of the residual gas component in coal massifs is investigated.The stages of change of qualitative and quantitative gas composition in coal massifs at gas – dynamic phenomena are established.The ways of gas migration in coal massifs and technogenic reservoirs are determined.The concept of rate gas saturation of a coal massif, which is controlled by the action of discontinuous tectonics, is introduced. Scientific novelty.For the first time, the conditions for the formation of modern gas-saturated zones in coal massifs due to gas migration and rate gas saturation have been determined.The influence of discontinuous tectonic disturbances on the migration and accumulation of gases in coal massifs has been established. Practical significance. The influence of gas migration on the formation of gas-saturated zones in coal-bearing massifs and man-caused reservoirs of the spent space of operating mines is established,which is important to ensure the safe operation of coal mining enterprises and degassing of coal massifs. Key words: gas-bearing, gas migration, tectonic disturbances, coal massif, man-caused collectors, Donets basin.

Allocation of Potentially Environmentally Hazardous Sections on Pipelines

The paper presents an analysis of the method of recording the magnetic component of the Earth’s natural pulse electromagnetic field in an urban environment. This method of recording has already proved itself to be a method that allocates the stressed sections of rock mass at mining and, therefore, the authors consider it effective for allocating active tectonic disturbances and forecasting accidents at underground utilities, which will help reduce the potential environmental hazard of these objects.

Allocation of Potential Emergency Sections on Pipelines

The paper presents an analysis of the method of recording the magnetic component of the Earth’s natural pulse electromagnetic field in an urban environment. This method of recording has already proved itself to be a method that allocates the stressed sections of rock mass at mining and, therefore, authors suppose its effectiveness for allocating active tectonic disturbances and forecasting accidents at underground utilities, what will help reduce the potential environmental hazard of these objects.

Specific Features of Mapping Large Discontinuous Faults by the Method of Electromagnetic Emission

In this paper, the authors consider the issue of processing the data of electromagnetic pulses (EMPs) recorded in mine workings and their interpretation. The Sami fault (Russia, the Murmansk region) was chosen as the object of the research. A number of experiments, including measuring the EMP level along the fault and the analysis of the results, were performed by the authors. The paper also presents a previously unconsidered method of transition from geological concepts to electro-technical ones, the aim of which is to identify the dependences of the amplitude of electromagnetic field anomalies on the parameters of active tectonic disturbances. The authors assumed the dependence of the amplitude of anomalies on the geological parameters of the rock mass and the thickness of the tectonic disturbance.