Vol 27 Iss. 2

The problem of metamorphism and transformation of coal matter is very complex. It involves questions of chemical transformation of organic matter in nature, on the surface of the earth's interior, questions of physical changes in coal matter under different conditions, questions of the impact of geological agents (temperature, pressure, mineralizers) and a number of others. Therefore, scientists of different specialties approach these questions somewhat differently and, based on different premises, often come to opposite conclusions. At the same time, sometimes what is only a hypothesis is presented as facts, and ignorance of factual material from a neighboring field of science sometimes leads to the denial of well-known facts and conclusions of this science on this issue. That is why the problem of coal metamorphism still remains unsolved. All these difficulties could be overcome if a comprehensive work on this problem was set up, which would include the joint development of all controversial issues by scientists of different specialties.

Hard rocks are widely used in construction. They often serve as a natural foundation for various structures, form the slopes of pits, canals, trenches and quarries. There are numerous examples of tunnels and galleries, as well as various industrial and special structures, being constructed in rocky rocks. Hard rocks are widely used as building and facing stone, in the preparation of crushed stone for concrete, road surfaces, ballast and other construction purposes. Engineering and geological assessment of rocky rocks should be based on the study of their mineralogical composition, structure, texture, bedding conditions, fracturing and weathering, i.e. on geological and petrographic features. Additional data for such an assessment of rocks should be the results of laboratory tests for temporary compressive strength, softening, porosity, water saturation, water absorption, frost resistance and abrasion. In some cases, all this is insufficient to assess the resistance of hard rocks to weathering agents. Therefore, in such cases, it becomes necessary to study rocks in laboratory conditions using a special method, which involves studying not only the general construction properties of rocks, but also their resistance to the effects of physical and chemical weathering factors. The results of such studies, conducted for one of the construction sites, are given below.

The issue of the influence of the specific gravity of groundwater on the conditions of its occurrence and movement is rather poorly covered in the literature. When studying fresh and slightly mineralized waters, their specific gravity is usually taken to be equal to 1, neglecting its minor changes depending on temperature, pressure and concentration of dissolved substances. However, when studying waters of increased mineralization (approximately starting with a total mineralization of 5-10 g / l) and especially brines, the increased specific gravity of water so strongly modifies the hydrodynamic conditions and affects the water level in wells (data used to determine the direction and speed of movement of groundwater), that conventional methods of calculations and constructions lead to gross errors and even complete distortion of reality. It is known that the presence of water of increased specific gravity in boreholes (caused by high mineralization or the content of suspended particles) leads to a decrease in the water levels in them, and to calculate the level corresponding to fresh clean water ("reduced level"), the following are introduced simple corrections. However, these corrections are still insufficient for calculating the movement of groundwater, which requires a significant modification of the usual filtration equations. The most difficult issue is determining the conditions of equilibrium, as well as the direction and speed of movement of groundwater with their variable specific gravity, especially when the specific gravity changes in the vertical and horizontal directions, which is usually observed in nature.

Until very recently, a common view of pegmatite genesis has not been established among a large circle of geologists studying pegmatite deposits. A. E. Fersman's theory of pegmatite formation is still widely popular. The enormous work of A. E. Fersman and his group of colleagues, aimed at collecting materials characterizing the mineral composition of pegmatites in almost all regions of the USSR, played a major positive role, attracting general attention to these deposits and thereby facilitating their rapid industrial development. This group of researchers rightly established that the formation of pegmatites is a very complex process occurring in changing physicochemical conditions and that, in accordance with changes in crystallization conditions, the paragenetic associations of the resulting minerals change. However, a number of fundamental provisions of A. E. Fersman's general theory of pegmatite genesis, as is known, have not been justified. A. E. Fersman's ideas that pegmatites are formed by means of successive crystallization in a closed system, the so-called pegmatite water-fire melt, highly enriched in volatile components, have long been met with objections.

Recently, a discussion has developed regarding the genesis of pegmatites. The beginning of this discussion was laid by D. S. Korzhinsky in 1937. In 1944, A. N. Zavaritsky demonstrated the inconsistency of the physicochemical substantiation of the pegmatite process proposed by Vogt and Niggli and accepted by A. E. Fersman. Later, in 1947, he put forward a new theory of the genesis of pegmatites, contradicting the idea that pegmatites are a product of direct crystallization of residual melt (A. E. Fersman's theory). According to A. N. Zavaritsky, the main structural features of pegmatites are created as a result of recrystallization of certain igneous rocks. Next, V. D. Nikitin, who studied ceramic and mica pegmatites (1946-1951), based on a detailed analysis of the relationships between individual minerals and structural components of pegmatites, developed ideas about the genesis of pegmatites of this specific type, which are basically consistent with the theory of A. N. Zavaritsky. However, much effort is still needed to more fully resolve issues related to establishing all the features of the transformations that both the deposits as a whole and the individual minerals that make them up undergo during the complex and lengthy process of pegmatite formation. This article highlights the main features of the evolution of feldspars in ceramic pegmatites of Southern Karelia.

The conditions for developing heavily flooded brown coal deposits in the Moscow Basin, located in unstable rocks, are determined by the features of their geological and hydrogeological structure. For deep-lying deposits in the southern and western wings of the basin, the main feature is the presence of a subcoal aquifer with a water pressure of up to 90 m. These pressure waters are the cause of water breakthroughs from the soil of mine workings. At the same time, clay strata lying in the soil of mine workings and protecting them from water breakthroughs from the subcoal aquifer are of decisive importance for the safe conduct of preparatory and cleaning mining operations. The thickness of the subcoal clay layer and its strength determine the need and scale of drainage measures during deposit development. All other things being equal, the need to reduce the pressure of subcoal waters and the magnitude of this reduction will depend on the minimum strength of clays. Facts show that under the action of hydrostatic pressure, the soil of mines workings will experience tension when bending. Therefore, to correctly select the scheme and volume of drainage works, it is necessary to know the ultimate tensile strength of clays, their temporary resistance. The temporary tensile strength is usually the smallest compared to the temporary resistance to shear (shear) and compression. Thus, the value of the temporary tensile strength of clays is the main calculation parameter for deciding on the need to drain mine fields. Meanwhile, the tensile strength of clays has hardly been studied. In numerous articles devoted to the development and drainage of brown coal deposits in the Moscow Basin, this issue has hardly been covered.

No systematic work on the study of mineral waters of Transcarpathian Ukraine was carried out before its reunification with the Ukrainian SSR. Individual sources from the point of view of their therapeutic use are briefly characterized in the Bulletin of the Czechoslovak Balneological Society. An attempt to summarize the knowledge of mineral waters of the Transcarpathian region is the work of F. Wiesner, which, however, mainly provides information on the geographical order of 200-odd mineral springs and completely lacks data on the chemical composition of these waters. The information at our disposal at present on the chemical composition of mineral springs of Transcarpathian Ukraine allows us to outline some preliminary patterns in the distribution of various types of mineral waters by area. The Transcarpathian region, which is a young mountainous country, is characterized by the wide development of mineral waters. The number of mineral springs, according to preliminary data, reaches three hundred.

In our report in January 1951 at a conference at the Central Institute of Balneology in Moscow and in an article published in the Notes of the Leningrad Mining Institute, the question was raised about the presence of carbonated mineral waters in Crimea and the need to study them to expand the resort and sanatorium base of Crimea. The work of 1951 completely confirmed the forecasts made. The presence of carbonated waters to the north of the city of Kerch, which we had noted based on the analysis of gas jets in 1950, was completely confirmed in the summer of 1951 by determining the free carbon dioxide in the water of some springs. Within the field of carbonated jets to the west of the city of Kerch, the content of free carbon dioxide in the springs of the Seit-Eli group was determined to be from 577 to 1180 mg/l. Samples for analysis were taken by S. V. Albov. The analysis was carried out by V. A. German in the laboratory of the Crimean Geological Department. Consequently, in addition to the carbonated spring of Kayaly-Sart, we can also talk about about the carbon dioxide springs of the Seit-Elin group.

In the practice of hydraulic engineering, one often encounters the following case of water inflow into a pit limited by a cofferdam. The pit is arranged in loose, practically homogeneous rocks, characterized by a constant filtration coefficient. Its bottom coincides with the aquiclude, the slope is determined by a certain slope coefficient m = ctg φ, constant along the entire height. The pit is limited by a cofferdam, composed of rocks, the filtration coefficient of which is very small compared to the filtration coefficient of the soils underlying the cofferdam. The cofferdam maintains a certain level in the upper pool. Water from the pool moves under the cofferdam and comes out onto the pit slope. In this case, in practice, the most common case is when, upon reaching the slope at point M, the underground flow is characterized as unconfined. At the same time, in the initial section of its movement under the cofferdam, the underground flow, limited from above by the base of the cofferdam and from below by the aquiclude, is under pressure.

Information on torpedoing hydrogeological wells as a method of increasing their flow rate is found in a number of works on hydrogeology and drilling. However, this method of exploring underground waters has not yet received wide application in the practice of hydrogeological research. This is explained by the lack of a developed torpedoing technique for testing hydrogeological wells. The proposed article examines some issues of the technique of torpedoing hydrogeological wells in order to increase their water content.

Thanks to the creation of high-quality domestic equipment for studying minerals and ores, spectral analysis methods are becoming increasingly important both in studying the material composition of deposits, host rocks, mineralization zones, etc., and in quantitatively assessing the content of ore components in them. Spectral analysis is of particular value in field conditions, increasing the efficiency of geological exploration and allowing a preliminary assessment of the objects under study. Experimental studies conducted by us on the material of studying copper pyrite ores allowed us to develop a method for rapid quantitative spectral determination of copper in field conditions without the use of complex additional equipment. Methods of quantitative spectral analysis are based on an unambiguous relationship between the intensity of the spectral lines of elements and the concentration of these elements in the substance under study. This relationship is established by comparing the spectra of samples and standards visually or with a microphotometer by measuring the blackening of the spectral lines.