Main Requirements Imposed by Design and Operating Organizations on Geologists Conducting Exploration of Quarry Fields

A. M. Chursanov

At the present time, greater attention is being devoted to the development of coal deposits by the open-pit method. Therefore, a significant increase in open-pit coal mining in Kuzbass is planned.

The open-pit method of mining hard coal has an enormous advantage over underground mining. As is known, with this method the labor productivity of workers is 5–6 times higher, while the cost, in comparison with underground coal mining, is 3–4 times lower. The construction of quarries is carried out 2–3 times faster than the construction of mines. Capital expenditures per ton of capacity are 1.5–2 times less than in underground mining, and the design capacity is brought into operation 4–6 times sooner. Enormous advantages with respect to the safety of those working in coal production, considerably better hygienic conditions, comparatively low losses, and the possibility of using complex mechanization all distinguish the open-pit method of development favorably in comparison with underground mining.

Prospects for Open-Pit Operations in Kuzbass

The exceptional conditions of many Kuzbass deposits make it possible to develop open-pit mining on a large scale in a short time. Despite this, open-pit coal mining in Kuzbass did not develop, and only in 1948 did coal begin to be extracted from the Bachatsky quarries. In 1953, coal production by the open-pit method amounted to 3.8%; in 1954, 5.6%; in 1955, 10.2%; and in 1956, 13.3% of total production. Thus, the share of coal production by the open-pit method in Kuzbass must be recognized as extremely low, especially if one takes into account the enormous possibilities of the basin in this direction.

The geologists of Kuzbass carried out extensive surveying and exploration work to identify new sites for quarries. If as of January 1, 1948, there were 7 reserve sites, then by 1953 the balance of explored and prospectively identified fields, according only to the work of the Kuzbassuglegeologiya trust, amounted to 32 sites. From 1953 to 1957, as a result of geological exploration work by the Kuzbassuglegeologiya trust and the West Siberian Geological Administration, enormous areas were transferred from prospective sites into reserve fields for open-pit operations.

The richest districts with a large number of reserve sites for quarries are: Tom-Usinsky, Mrassky, Kondomsky, Baida-

evsky, Erunakovsky, Kiselevsky, Bachatsky, Leninsky, Kemerovsky, and Itatsky (Chulym-Yenisei Basin).

In 1956 the Kuzbassuglegeologiya Trust identified 100 reserve areas in Kuzbass and 15 areas in the Chulym-Yenisei Basin (Itat). In doing so, the calculation of such areas was carried out very modestly, since only small mining depths and a low stripping ratio were taken.

Thus, for example, in the Bachatsky central and southern areas, reserves for open-pit mining with a stripping ratio of 3.8 were calculated down to a depth of 140 m, whereas there is every reason to calculate them down to a depth of 220–250 m, which will increase the reserves by 40–45%. In the Kedrovsky and Khorosheborsky areas, stripping ratios of 0.9–1.3 and an open-pit mining depth of 40–60 m were adopted, whereas mining can be carried out to a depth of 100 m. In the Novosergeevsky area, instead of the adopted mining depth of 110 m, 250 m may be adopted.

The author has calculated the reserves and determined the possible capacity of open-pit coal mining in the Tom-Usinsk and Mrassk districts. The calculation shows that in these two districts it is possible to build about 43 large and medium-sized quarries with an annual capacity of up to 104 million tons of coal. The geological reserves of these quarries are estimated at more than 6 billion tons. The stripping ratio in all areas, except the Raspadsky areas, is 4–9 m³/t.

In the Itat areas in the Chulym-Yenisei Basin, output can be brought up to 130–150 million tons per year.

Thus, one may conclude that, taking into account promising areas, and when mining coal seams at deeper horizons, more than 300 million tons of coal per year can be extracted by the open-pit method in Kuzbass together with Itat. But even if this distant prospect is not taken into account, and the more modest calculations for 100 areas are used—areas that will be mined with a stripping ratio of 0.9–6 m³/t—then it is possible to bring coal production from open-pit workings in Kuzbass together with Itat to more than 200 million tons per year. It should be noted that of the 100 areas identified in Kuzbass, 34 contain coking coals, where an annual coal-production capacity of up to 30 million tons can be developed.

Integrated Design and Mining of Areas by Quarries

Long experience in developing mineral deposits has shown that at present it is impossible to design a mine or quarry without knowing the entire complex of minerals not only in adjacent areas, but also in the nearest areas. In accordance with this, technical structures, access roads, residential settlements, and so forth must be located. Unconsidered prospects for the development of the area or deposit as a whole, on which an enterprise is being built, may entail enormous overspending of state funds for its reconstruction. An example of this is the costly reconstruction of Korkinsky quarries 1 and 2.

Geological exploration, design, construction, and operating organizations must maintain close contact in their day-to-day work. It cannot be said that such contact among the indicated organizations in Kuzbass does not exist; nevertheless, many issues of integrated design and development of deposits are still being resolved inadequately. Thus, using the examples of the Tom-Usinsk and Mrassk districts, which are richest in reserves of coking and high-quality steam coals, it can be shown,

Figure 1. Geological section of the central part of the Tom-Usa region (along exploration line I–II).

1 — coal seams; 2 — core-drilling boreholes; 3 — diabases; 4 — tectonic faults; 5 — boundary of the quarries between groups I and II of seams.

that comprehensive design is not being given due importance here. In these two districts, only in the first, incompletely explored belt, with a strike length of about 72 km of the coals, there occur two groups of seams: the first group—from seam I to seam XVII, and the second—from seam XVII to seam XXXV (Fig. 1). The first group has 11 workable seams, and the second 18 workable seams. The data given above on 43 large and medium quarries in the Tom-Usinsk and Mrass districts have been determined with allowance for the joint working of these two groups of seams.

The thoroughly explored areas: Kiizak 8 and the area of the Tom-Usinsk 3–4 quarry under construction, show that such fields must be designed as a complex and worked jointly. Only with the joint working of four quarry fields—Tom-Usinsk 3–4 and Kiizak 8, Tom-Usinsk 7–8 and Kiizak 9, Sibirginsk 1 and Kiizak 10, Sibirginsk 2 and Kiizak 11—down to the horizon of −350 m do the potential reserves for open-pit coal mining increase by 800 million tons.

Meanwhile, despite the favorable occurrence of the seams and a low stripping ratio of 4.4–9, design is being carried out strictly individually for each group of seams on which quarries will be laid out. For example, the Tom-Usinsk 3–4 quarry under construction has been designed only down to seam VI.

In the projected quarries Tom-Usinsk 7–8, Sibirginsk 1 and 2, Kurein and Uregol, it is planned to work only the upper seams from I to VI; the lower seams from VI to XVII will be used for underground mining.

No one among the designers and operating personnel is yet interested in the seams of the second group. Some are alarmed by the presence of thin seams (from 1.5 to 3 meters), which occur among the thick seams of the first and second groups. However, it is known that at present this question is not a problem, since in foreign [3] and domestic practice there are many examples of working thin seams with special combines or auger-boring machines [5].

The absence of comprehensive design in the Tom-Usinsk and Mrass districts, which are richest in coal reserves for open-pit operations, narrows the front for coal production by the open-pit method.

Procedure for Laying Out Quarry Fields

Under conditions of complex relief, the presence of intrusive rocks and water basins, it is necessary to approach the determination of the boundaries of a quarry field with particular care. We distinguish 4 types of boundaries: 1) geomorphological, 2) tectonic, 3) igneous-rock, 4) conditional (economic).

Geomorphological boundaries should include deep gullies and ravines that cut across the strike of the coal seams or at a small angle, deeply incising the country rocks. Thus, for example, the boundary of the quarry fields Sibirginsk 1 and Sibirginsk 2 in the Tom-Usinsk district is a ravine—the relative excess of the average elevations of the area above the floor of the ravine is more than 100 meters. Boundaries caused by water basins belong to the same type. The Tom-Usinsk and Mrass deposits are crossed by three comparatively large rivers—the Usa, Tom, and Mrass—and by small rivers: Olzherass, Kiizak, Mzas, Tobolas, and others. In mining practice there is experience in diverting rivers. It is possible that in the Tom-Mrass district such small rivers as the Kiizak can be diverted for some distance; but diverting the Tom and Mrass rivers under mountain conditions is quite complicated and expensive.

Tectonic boundaries may impart to quarry fields

the most unexpected forms. Fold zones range from several meters to several hundred meters. A major dislocation, whether it extends along the strike, at an angle, or across the strike, will always constitute a boundary of the quarry field.

Igneous rocks in the Tom-Mrassky district, cutting through the productive deposits, divide the deposit into parts. If in such areas the coal seams are suitable for open-pit mining, then, because of this, the quarries will be far from equal in area and productivity, although under normal conditions they could have been laid out identically.

In the Tom-Usinsk and Mrassky districts, intrusive rocks—diabase sills—often follow the bedding of the productive deposits, repeating the folds of the coal seams or cutting them at an acute angle. Igneous rocks up to several tens of meters thick, located in the anticlinal fold of the second group of seams in the northwestern part of the Sosnovsky and Beregovoi sectors, do not make it possible to lay out the quarry fields of the two sectors uniformly. Nevertheless, the western limb of the fold will be worked by one quarry, and the eastern limb by another. In the absence of diabases, these two sectors could have been worked by one large quarry.

It would be incorrect to regard igneous rocks only from a negative point of view when laying out quarry fields. They can also play a positive role in the mining of coal seams, since they may serve as stable barriers in the sides of quarries, holding the rocks against collapse, or serve as a water-bearing horizon in the floor of the lower seam of the quarry, contributing to the preservation of internal dumps. This study must be carried out in the course of detailed exploration.

Conventional boundaries are drawn in deposits that do not have deep ravines, rivers, lakes, tectonic faults, or igneous rocks. The dimensions of quarry fields in such deposits are determined depending on commercial reserves, the mining-and-transport equipment used, and the prospects for development of the district.

Within the outlined boundaries, the production capacity and service life of the quarry are calculated.

Engineering-Geological Work

For the proper organization of open-pit coal mining, a preliminary study is required of the engineering-geological and hydrogeological conditions, as well as of the physical and mechanical properties of the rocks, which predetermine the economics and even the technological scheme of mining. Requirements for the engineering-geological degree of study of quarry fields increase sharply in comparison with exploration of mine fields; moreover, in this case the object of study must be the entire thickness of the rocks, both overburden and those between the coal seams, over the entire area of their occurrence.

The main purpose of engineering-geological investigations, carried out in this case according to a special program and methodology, is to substantiate measures to ensure the stability of the sides and bottom of the quarry.

In the practice of mining enterprises there are many examples where poor study of engineering-geological conditions and of the physical and mechanical properties of rocks has led to major accidents. There are especially many collapses and landslides in quarries where extraction is accompanied by exposure of a wide front of enclosing rocks and coal that are not secured in any way. Meanwhile, before the na—

Until recently, the geological-exploration organizations of Kuzbass have engaged almost not at all in studying the physicomechanical properties of rocks in the areas where quarries are to be constructed.

Of greatest interest, when evaluating the complex of overburden rocks and productive deposits from this point of view, are clayey deposits, and sometimes sands and weakly cemented sandstones, which under certain conditions are capable of acquiring the properties of quicksands.

The study of these deposits must be carried out with due regard for engineering-geological phenomena that may arise when the quarry is opened. Thus, for clayey deposits it is necessary to determine the limits of elastic and plastic deformations and other indicators, including mineralogical composition, composition of exchangeable cations, degree of enrichment with humic substances, and activity of interaction with atmospheric agents.

In addition to ordinary laboratory physicomechanical investigations, field tests should be carried out to determine the shear angles of rocks, the parameters of which determine the general slope angle of the working and nonworking walls. Taken as a whole, all this will make it possible to assess the probability of landslides of the quarry and trench walls, the possibility of rock heaving, etc.

For weakly cemented sandstones, the limits of mechanical elasticity, the composition and character of the cement, and the degree of enrichment with humic substances are of special interest; these are necessary for assessing the possibility of suffosion.

Among other features of engineering-geological investigations of quarry areas is the need for the most thorough study of deposits possessing weak water yield, since it is precisely these deposits that usually constitute the centers where landslides originate. Further, it is necessary to study in detail the hypsometry and dip angles of the floors of coal seams in order to resolve the question of the rational placement of internal dumps (or even the abandonment of the latter). Special attention must be paid to identifying the presence and conditions of occurrence of subcoal (usually artesian) waters, in connection with the frequently arising need to drain the base of internal dumps.

It should also be taken into account that it is necessary to evaluate the degree of stability of natural slopes along the working and especially the nonworking wall of the quarry, in connection with the disturbance of the equilibrium of earth masses when they are undercut by the quarry, as well as the need for a detailed study of buried landslides, which are widespread both in the productive strata and in the overlying deposits.

Petrographic study of the composition of the enclosing rocks in Kuzbass was not carried out for several years. True, at the present time it is being carried out, but it is reduced mainly to determining free silica in rocks of one or another lithological variety. At the same time, it is known that even the most insignificant, barely noticeable changes in the petrographic characteristics of a rock are reflected in its physical properties and mechanical indices. Especially great in this respect is the role of the chemical composition and the character of cementation of rocks, their structure, mineralogical composition, and degree of weathering.

In areas intended for open-pit operations, it is necessary to study carefully the structure and texture of rocks, which are needed for determining the type of mining machines, drilling hammers, bits, etc. Facts concerning the role of rock structure are well known. Thus, for example, the compressive strength of fine-grained granite reaches 2600 kg/cm², whereas that of coarse-grained granite does not exceed 1500 kg/cm². The strength of coarse-grained marble ranges from 800 to 1200 kg/cm², while that of fine-grained limestone...

exceeds 2500 kg/cm². The strength of diabase is usually not more than 3000 kg/cm², while the strength of cast (artificial) diabase, distinguished by a finer-grained structure, is above 5000 kg/cm². In general, it has been established that the strength of cemented rocks may vary, depending on their structure, by a factor of 2–3.

The texture of the rock has no less significant an influence. A massive-crystalline structure determines the quasi-isotropy of the physico-mechanical characteristics. It is known that bedding, schistosity, platy structure, and fluidality sharply disturb the quasi-isotropy of rocks [1; 6].

The jointing (cleavage) of coal has not been studied at all in many geological parties. Thus, in geological reports, when describing the physical properties of coal, they most often confined themselves to a conventional subjective characterization—“strong coal” or “weak coal.” As is known, jointing (cleavage) plays a major role in mining operations. A correct assessment of jointing makes it possible to carry out a rational arrangement of mechanisms in the working face, which helps increase the productivity of one or another type of mining machine [2].

When selecting the set of indicators of physico-technical properties in each specific case, those hazardous engineering-geological phenomena must be taken into account which may arise in interaction with the natural setting. Thus, in the construction and operation of quarries, the following acquire the most essential importance: assessment of the water abundance of workings (filtration coefficient and water yield of rocks), the degree of stability of the walls (angle of internal friction and magnitude of cohesion, unit weight of rocks), the possibility of suffosion phenomena arising (grain-size composition of loose rocks), the correct choice of the design of drainage devices (grain-size composition), the possibility of a breakthrough of subproductive pressurized waters when the water-retaining barrier along the bottom of the quarry is cut through (temporary tensile strength), the possibility of deformation of slopes due to the extrusion of clayey rocks along the base of benches (modulus of deformation, temporary compressive strength, parameters of the compression curve, unit weight of rocks), the behavior of clayey rocks in quarry slopes (hydrophilicity of rocks, mineralogical composition, exchange cations, humus enrichment, mineralization of groundwater), the possibility of quicksand manifestation in quarry slopes (mechanical composition, content of colloidal particles and humus, water yield, thixotropic properties), and the corrosive effect of mine waters on metal equipment and concrete (the chemical composition of groundwater is usually determined in hydrogeological investigations).

The engineering-geological phenomena possible during the construction and operation of quarries, as well as the indicators of the physico-mechanical properties of rocks that must be obtained during exploration of quarry fields, are shown in Table 1.

Study of climatic conditions during geological exploration work

Climate is one of the leading, and sometimes the principal, factors determining the degree of labor intensity involved in developing mineral deposits.

Indeed, the conditions for working deposits associated with permafrost depend almost entirely on the nature of the climate. The amount of atmospheric precipitation replenishing the reserves of groundwater and surface water, the nature of its distribution over the year, the magnitude of evaporation, water infiltration, etc., also depend on climatic features. Climate may rightly be called the regulator of groundwater resources.

Table 1

Necessary indicators of rock properties in the construction and operation of quarries

Continuation of Table 1

If, under the conditions of the Kuzbass, climate is of secondary importance in the underground mining of coal, then in open-pit operations it assumes a leading role. Let us consider some of the climatic factors separately.

Atmospheric precipitation is one of the most important elements of climate. It is sufficient to say that the principal characteristic of climate and its subdivision into types are determined according to the amount of precipitation.

In assessing the role of atmospheric precipitation in the recharge of groundwater, in addition to the quantitative aspect, the character of the precipitation is of great importance. The most favorable conditions for the infiltration of atmospheric precipitation are created by prolonged drizzling rains; conversely, during downpours, which are usually of short duration, the main part of the water is spent on surface runoff. The distribution of precipitation over the year is a very important point. In some regions the bulk of the precipitation falls in the winter period, in others in the spring–summer period, and so on.

Atmospheric precipitation falling directly within quarries in the form of episodic downpours is of particular significance. For example, in June 1948 in the Kuzbass (the Topki–Leninsk-Kuznetsky district) there was a downpour that lasted for 1 hour. In this short interval about 0.1 of the annual amount of precipitation fell, i.e., about 40 mm. With such a downpour, over a quarry area of 1 hectare the water inflow due to atmospheric waters would amount to 400 m³/hour. Such a colossal quantity of water can quickly fill all the low-lying parts of the quarry and cause serious consequences.

The negative influence of fluctuations in temperature as one of the climatic factors in the conduct of open-pit operations is quite obvious. Without speaking of the general difficulties of working in a quarry during periods of severe frost, as well as the technical difficulties associated with them, let us dwell on complications of a physical-geological character. A change in temperature causes a change in the strength of the ground. The strength of frozen rocks exceeds the ordinary strength by tens of times or more, owing to the formation of ice crystals binding the individual particles.

Depending on the character and duration of the cold period, the same rocks may possess different resistance to excavation, which cannot fail to affect the productivity and cost of the work. A second aspect of the negative influence of temperature fluctuations is the change in the stability of benches and slopes of quarries.

Landslide phenomena are also promoted by the partial thawing of the ground, when its upper, already thawed and softened part slides along a layer of still-frozen ground.

Wind in open workings is also a significant factor, and underestimation of it often leads to unfavorable consequences. The action of wind may be regarded as a positive factor when it appears possible to create natural ventilation in the quarry. Underestimation of wind in design may also lead to major accidents in the quarry. Thus, at the Aleksandrovsk coal open-pit mine in Ukraine, a dump bridge was overturned by the wind.

To understand the full complexity of work in quarries under fog conditions, it is enough to realize that the main “life” of a quarry is connected with transport (especially motor transport). The movement of transport in fog, as well as excavating and hoisting operations, is many times more difficult than under night-time conditions. The speed of movement, and hence the overall productivity of transport, decreases sharply.

Pressure, air humidity, and evaporation are closely interrelated, both with one another and with other elements of climate (temperature, wind, etc.); therefore they too must be studied carefully.

Exploration of the Upper Horizons and Tracing of the Oxidized-Coal Zone

At present, the Kuzbassuglegeologiya Trust very often has to carry out exploration on fields that were previously explored in detail. The lack of a well-developed methodology for exploring fields for open-pit mining in Kuzbass as a whole, and separately for each type of deposit in the basin, creates great difficulties in preparing a quarry for operation. Particularly many claims were made against geologists concerning the fields of the Tom-Usinsk and Mrassk districts. In this work, taking into account the extensive experience of the Kuzbassuglegeologiya Trust, we make an attempt to develop the density of the exploration grid at each of the stages of geological exploration work. In our opinion, this grid will ensure more effective preparation of quarries for operation.

Preliminary exploration must be carried out on a grid with distances between exploration lines of 1200 m and between boreholes on a line of 600 m. The latter ensures double intersection of one and the same seam (Fig. 2). This stage of exploration makes it possible to decide whether it is expedient to mine the seams by underground or open-pit methods. If the decision is made in favor of open-pit development of the deposit, the grid of exploration workings is made denser. The distance between exploration lines is taken, for stable coal seams of reserve category B, as 600 m, and for relatively stable seams, 400 m. For reserves of category A₂, the indicated distances between exploration lines are reduced by half. The distances between boreholes on lines at the working horizon must correspond to half the distance between exploration lines. Special attention should be paid to horizons close to the surface, and especially to the outcrops of coal seams beneath the overburden. The increase in the higher categories A₂ + B must, in this case, fully ensure the initial development of coal extraction. Table 2 below gives the density of the grid of exploration boreholes for detailed exploration of deposits in the quarry fields of the Tom-Usinsk and Mrassk districts.

Table 2

In the conditions of the Tom-Usinsk and Mrassk districts, it is advisable to explore seam outcrops in complex relief by means of pits and trenches, while taking the distance between individual workings along the strike of the seam as from 75 to 100 m. In places of first-priority stripping, at the stage of overburden exploration, it is desirable to reduce them to 40–50 m.

Fig. 2. Geological sections along the exploration lines of the Tom-Usinsk 7–8 quarry.
1—drilled boreholes; 2—required boreholes.

![Map diagram]

Fig. 3. Map of coal-seam outcrops beneath the overburden of the Tom-Usinsk 3–4 quarry (based on detailed exploration data).

1 — coal-seam outcrops beneath the overburden; 2 — burned-out seams; 3 — diabase dike; 4 — core-drilling boreholes; 5 — tectonic faults; 6 — adits.

Fig. 4. Map of coal-seam outcrops beneath the overburden of the Tom-Usinsk quarry 3–4 (according to supplementary exploration data). (Symbols are the same as in Fig. 3).

Such densification is especially necessary in areas with complex geomorphological elements, when graphical plotting of the coal-seam outcrops beneath the overburden cannot be sufficiently accurate. The latter can be traced in the example of the Tom-Usinsk quarry 3–4 (Figs. 3 and 4). In the indicated figures, the dependence of the accuracy of constructing the map of coal-seam outcrops beneath the overburden on the degree of exploration by small mine workings and boreholes of the coal outcrops beneath the overburden is clearly visible. Figure 3 shows an area explored in detail, the report on which was approved by the VKZ. Figure 4 shows the same area after additional exploration had been carried out.

The contouring of burnout zones of coal seams should preferably be carried out by pits that pass along the contact with the seam not affected by an underground fire, in combination with core-drilling boreholes, which are drilled in order to determine the depth of burnout.

In exploring the burned-out zones of coal seams, it is recommended to use the dependence of the spread of burnout on the groundwater level. In Figure 5 we give an example of graphical construction of the boundary of seam burnout as a function of the groundwater level.

Fig. 5. Dependence of coal-seam burnout on the level of groundwater in the field of the Sibirginsky 2 quarry.
1 — seam outcrop beneath the overburden; 2 — hydroisohypses of groundwater; 3 — isohypses of the seam roof; 4 — boundary of the seam-burnout zone, constructed by intersecting the isohypses of the seam roof and the groundwater level with identical elevations; 5 — boundary of the seam-burnout zone, constructed from mining-exploration workings; 6 — core-drilling boreholes.

This method of determining the boundaries of burnout of coal seams will significantly reduce the cost of exploration of the area.

Complicating factors in the exploration of the Tom-Usinsk and Mrassk areas for open-pit operations were the extremely complex relief and, as a result, the presence of complex, peculiar forms of seam outcrops beneath the overburden. In addition, exploration is complicated by the presence of sills and

dikes of diabase, ancient and modern landslides, as well as burned-out areas of coal seams.

A correct approach to determining the exploration grid can be achieved by taking into account all factors and features not only of the deposit as a whole, but also of its individual sections. Practice has shown that one section requires densifying the exploration lines and the boreholes on the lines; in other sections, such densification will lead to needless overspending of state funds.

References

1. Baron, L. I. On strength indices of rocks. Proceedings of the Academy of Sciences of the USSR, Department of Technical Sciences, No. 11, 1948.

2. Belitskii, A. A. Important tasks of mine geology in the coal industry. Coal, No. 1, 1954.

3. Gluckauf. Die Entwicklung und Verbreitung von Gewinnungs und Zademaschinen in Ausland. 19/20 of 8/V-54.

4. Melnikov, N. V. Handbook for Engineers and Technicians in Open-Pit Work. Ugletekhizdat, 1952.

5. Melnikov, N. V.; Simkin, B. A. Combines and Auger-Drilling Machines in Open-Pit Coal Mining. Moscow, Funds of the Academy of Sciences of the USSR, 1956.

6. Paniukov, P. N. A Short Course in Engineering Geology. Ugletekhizdat, 1956.

7. Priklonskii, V. A. Soil Science, Vol. I, 1949; Vol. II, Gosgeolizdat, 1952.

8. Savarenskii, F. P. Engineering Geology. GONTI, 1939.

9. Sudoplatov, A. P.; Baranovskii, V. I. On the development of scientific research in the field of coal-deposit development. Coal, No. 4, 1953.

10. Syrovatko, M. V. On the role of engineering-geological factors in the development of landslides during open-pit mining of brown-coal deposits. Soviet Geology, Collection 56, 1956.

11. Sheshko, E. F. Fundamentals of the Theory of Stripping Quarry Fields. Ugletekhizdat, 1953.

Kuzbassuglegeologiia Trust