As we know, the natural environment includes the atmosphere, hydrosphere, biosphere and geosphere (geological environment). Each of these spheres is studied by special sciences, specialists of a certain profile.
The impact of human industrial activity on the geological environment on its scale, diversity and results reaches nowadays values commensurate with natural geological phenomena.
The problem of environmental protection during the development of mineral deposits is extremely complex. Construction and mining works are carried out within many basins, ore belts and zones in thousands of deposits of various types of minerals.
Every territory on Earth with its relief, geological formations, processes and phenomena represents the geological environment of human life and activity. In brief, the geological environment is the surrounding geological conditions.
Engineering geology is fifty years oldEngineering geology is one of the youngest Earth sciences. As an independent field of geological knowledge sleep began to take shape in 1929, when the Central Institute of Hydrogeology and Engineering Geology was established instead of the Groundwater Division of the Geological Committee ...
One of the new, successfully developing scientific directions of engineering geology is engineering geology of mineral deposits. The field of research of this direction includes a wide range of geological issues and practical problems arising in the development of various mineral deposits: ore, coal, mining and chemical raw materials, construction materials, etc.
In the successful implementation of the construction plan and the development of vast territories an important role is played by design, outlining the rational geographical location of various types of construction and the economically most profitable implementation at high rates. In this light, the regional engineering-geological study of certain areas of the USSR on the basis of generalization of available materials and setting special studies is of great importance.
Distribution, stratigraphy and conditions of occurrence. On the territory of Leningrad, in its vicinity, along the valley of the Neva River, late-glacial ribbon clays are widespread. They were formed in a glacial lake basin, which developed as the glacier retreated. Remains of freshwater fish have been found in these sediments, according to which S. A. Yakovlev attributed the sediments to the sediments of Fish Lake. The ribbon clays are laid down in an almost continuous thickness of 2-15 m on the uneven surface of moraine (second moraine) or transitional from moraine to lake-glacial sediments. In some places they are completely eroded. In one or two places on the territory of Leningrad, in many areas in its vicinity and along the Neva River valley, the ribbon clays come directly to the surface. On the rest of the territory they lie at different depths under postglacial sediments - lithoric, ancient Baltic or modern alluvial and lake-bog deposits...
General characteristics of clayey rocks. Lignite deposits of the Moscow region are located in complex engineering and geological conditions, without taking into account which mining and cleaning works are extremely complicated. Among the phenomena causing difficulties in the development of the fields is the swelling of clayey rocks exposed by mine workings. Plastic clays are the most widespread among the clayey rocks of the coal-bearing horizon of the Moscow Region. They are the main host rocks for coal deposits, composing their soil and roof, or forming intercoal interlayers.
Under the influence of weathering agents, the state, composition and properties of clayey rocks can change significantly. Naturally, in different types of clay rocks these changes are manifested differently, depending on the composition, degree of lithification, conditions of occurrence, different geochemical conditions of existence of rocks in the bowels of the earth and prevailing in its surface horizons. When solving construction problems, any changes in the strength and stability of clayey rocks during weathering are of great importance and should be taken into account.
In engineering geology, clayey rocks are considered as some multiphase systems consisting of mineral particles, water and air. The mineral particles, forming the skeleton of the rock, are in most cases the main constituent of the rock. Water and air fill the spaces between the mineral particles in the rock pores. The rock pores may contain only air or only water, or air and water together. In some cases, the water filling the rock pores may be in a solid state (as ice). The degree of moisture in the clay rocks changes their state and they can be two or three or in some cases even four-phase systems.
Distribution, stratigraphy and conditions of occurrence. Cambrian age deposits on the Russian platform are ubiquitous along the southern subterranean slope of the Baltic Shield. They occur in natural outcrops or mainly under the cover of Quaternary sediments, in the area of the preglacial belt along the coast of the Gulf of Finland and Lake Ladoga, in the Neva Depression near Leningrad.
One of the most important issues related to engineering-geological study of clayey rocks is their classification. Classification of rocks, including clayey rocks, should determine the methodology of their study, facilitate the assessment of their properties and, accordingly, the stability of structures erected on them or engineering reclamation measures.
The behavior of rocks under the impact of certain structures on them is determined by their geological, petrographic, physical and mechanical properties. These properties they acquire in the course of natural-historical processes of formation and subsequent change in the bowels of the Earth's crust under the influence of various factors. The question of formation of construction properties of rocks was first put forward by the founder of Soviet engineering geology, Acad. F. P. Savarensky. He and with his participation carried out the first major studies in this direction. Many geological specialists took part in the subsequent development of this issue. The works of B. M. Gumensky, N. Y. Denisov, G. S. Zolotarev, N. V. Kolomensky, G. A. Mavlyanov, V. A. Priklonsky, I. V. Popov, P. N. Panyukov, I. I. Trofimov and other Soviet scientists are devoted to the study of the peculiarities of the formation of the properties of clayey rocks. Consideration of the conditions of clay sediment formation shows that the first stage of sediment formation is the accumulation of finely dispersed material by mechanical or chemical means. Depending on the conditions of accumulation of this material, sediments of different composition, properties and state are formed.
In the diagenetic processes of clay deposits, one of the most important is the process of dehydration of various silicates and aluminosilicates, which make up the bulk of their mineral part. Dehydration usually begins from the moment of sedimentation and causes a change not only in their physical state, but also in the composition of the moisture they accumulate. In parallel with the dehydration processes, complex physicochemical changes in the constituent mineral formations and sediment cementation occur in clay deposits. The ability of clays to dehydrate is determined by their relationship to water and aqueous solutions. According to modern concepts, this relationship should be considered as an active physicochemical interaction between the surface solution or solvate shell of clay particles and the external environment containing other dissolved substances. It is believed that the true surface solubility of clay particles in water determines the colloidal nature of clays.
In the Moscow Basin, clay deposits occupy a significant part of the section of the sandy-clayey coal-bearing suite of the Lower Carboniferous. This suite is almost continuously distributed throughout the basin (Fig. 1). Throughout its length, it is characterized by the inconsistency of the section in the vertical and horizontal directions. Along the southern wing of the basin, the coal beds are thicker, while to the north, along the western wing, the coal content of the suite gradually decreases, and already in the section of the Tikhvin region only black carbonaceous clays and occasionally thin coal interlayers are observed. At the same time, the saturation of the section with refractory clays is significantly reduced here, the place of which is occupied by bauxite deposits and red sandy clays. The variability of the section of the coal-bearing suite is explained by the coastal-marine and coastal-continental conditions of its accumulation. The change in the structure of the coal-bearing suite along the strike is the result of the facies replacement of coal by carbonaceous clays, and then carbonaceous clays by red sandy clays. A. E. Ulmer believes that the southern part of the western wing and the southern wing of the Moscow Basin are included in the facies zone of accumulation of continental and coastal-marine sediments, and the northern part of the western wing is included in the facies zone characterized by the predominance of continental erosion over accumulation.
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 Central Committee of our party and Comrade Stalin personally have always paid and continue to pay great attention to the ideological training and education of personnel. This work is acquiring enormous importance now, when our country is going through a significant period of transition from socialism to communism. In accordance with the resolution of the Central Committee of the All-Union Communist Party (Bolsheviks) on the journals "Zvezda" and "Leningrad", Soviet scientists were given the task of reviewing the development paths of individual branches of science, intensifying the fight against anti-scientific trends, the worship of foreign science and technology, and restoring the priority of Russian science. A sure means of combating the shortcomings of any work is criticism and self-criticism. "It is generally recognized," Comrade Stalin points out, "that no science can develop and succeed without a struggle of opinions, without freedom of criticism." This instruction from Comrade Stalin is of particular importance for engineering geology, the youngest of the geological disciplines, the history of whose development spans only two decades. Naturally, many provisions in engineering geology have not yet been sufficiently developed and formulated, and some are completely incorrect and erroneous. The present article is devoted to a critical examination of some of these provisions.
Studying the conditions of squeezing water and oil from clays is of exceptional importance for understanding the genesis of oil, oil fields, the formation of the salt composition of groundwater and the properties of clay sediments. Squeezing water and oil from clays is associated with the issue of clay compactibility. Clay compactibility has been studied many times, and there is extensive literature devoted to this issue. However, all these studies, in most cases, were conducted for engineering and construction purposes. Therefore, clay compaction was studied, as a rule, under low loads (4-6 kg/cm2). In addition, these studies were usually carried out to obtain the physical and mechanical characteristics of the soil. Only a few works are devoted to studying clay compactibility under higher loads.
The main iron ore strip of the Krivoy Rog basin is located along the right slope of the Saksagan River valley. Only in the lower reaches of the river does it also pass to the left slope. In this area, under the river bed and in the coastal protective pillars, there are large reserves of ore with a high iron content. At present, these reserves are not being developed, since there is a fear that with the development of the ore deposits, the surface of the earth will collapse and the river will flood the mine workings. In order to expand the operational capabilities of the basin, it is proposed to regulate the flow of the Saksagan River by accumulating reservoirs, one of which - Dzerzhinskoe - will be located in the lower reaches of the river, i.e. in close proximity to the exploited areas. In this regard, the question arises about the possible influence of the designed reservoir on the change in the hydrogeological conditions of the mines in this part of the Krivoy Rog basin. The very interesting data we collected during our surveys in the summer of 1945 field and archival material allows us to draw very definite conclusions on this fundamental issue, which is the subject of this article.
