QUESTIONS OF THE GEOLOGY OF KUZBASS, 2
PROCEEDINGS OF THE TOMSK ORDER OF THE RED BANNER OF LABOR
POLYTECHNIC INSTITUTE named after S. M. KIROV, vol. 99, 1959

MAIN FEATURES OF THE TECTONICS OF THE WESTERN PART OF THE KARAGANDA BASIN, OBJECTIVES AND METHODS OF FURTHER STUDY

A. A. KOSTLIVTSEV

Further development of the Karaganda basin is envisaged mainly through the development of its western part—the Churubai-Nura and Tentek districts. Both of these districts contain the basin’s most valuable coals—low-ash coking coals of the Dolinka suite. The Karaganda Metallurgical Plant, a giant project of the 6th Five-Year Plan, now under construction, will be based on these coals.

Because of the great thickness of the cover of Cenozoic deposits in these districts, other types of exploration of the coal-bearing strata, apart from mechanical drilling, are almost not used. The Churubai-Nura and Tentek districts have complex tectonics. Meanwhile, drilling reveals only the largest faults, whose amplitude is measured in tens of meters and more. Minor faults, as a rule, are not detected by boreholes and consequently are not studied during exploration. It is known, however, that minor faults, because of their abundance, present considerable difficulties during mine construction and especially during mine operation.

At present, almost the entire area of the western part of the Karaganda basin has been covered by detailed or preliminary exploration. In the Churubai-Nura district, mine No. 6/7 has recently been put into operation, and several more mines are under construction.

On the basis of materials from exploration of mine fields and from documentation of mines under construction, numerous geological reports are available. However, no special work has been carried out to study the tectonics of the western part of the Karaganda basin. Taking into account the need for such work, the trust “Kazakhuglegeologiya” of the Ministry of Coal Industry of the USSR included in its work plan for 1957–1958 the research topic: “Tectonics of the western part of the Karaganda basin.”

As a result of carrying out the indicated work, it is proposed to determine the interrelationship and character of all structural elements—folds, jointing, major and minor tectonic disturbances—and, on the basis of these generalizations, to provide a forecast of faulting for the mine fields of the western part of the Karaganda basin.

The Karaganda basin is an east–west-trending synclinorium composed of Devonian and Carboniferous rocks—

of age, by Mesozoic and Cenozoic deposits (Fig. 1). The basement of the basin is a Cambro-Silurian sequence, considerably more strongly dislocated and metamorphosed than the Devonian and Carboniferous rocks that lie transgressively upon it and that were not affected by Caledonian tectogenesis. The Devonian deposits begin with effusive—

Legend to Fig. 1

• Effusive–fragmental sequence of the Devonian and Silurian.
• Limestones and marls of the Devonian and Carboniferous.
• Dolinka and Tentek formations.
• Karaganda Formation.
• Axes of folds.
• Fault disturbances.

Along V–G–D–E

Churubai–Nura trough
Tentek anticline
Dolinka syncline
Alabas uplift
Karaganda trough

Along A–B

Legend to sections

• Effusive–fragmental sequence of the Devonian and Silurian.
• Limestones and marls of the Devonian and Carboniferous.
• Dolinka and Tentek formations.
• Karaganda Formation.

Fig. 1. Tectonic scheme of the western part of the Karaganda coal basin (Mesozoic and Cenozoic deposits not shown).

—rocks, their tuffs, and interbedded sandstones and shales, with a total thickness of 2 thousand m.

Above lies a complex of sedimentary rocks underlying the coal-bearing deposits. It consists of a conglomerate–sandstone formation of Givetian and Frasnian age, up to 200 m thick, and a limestone–shale sequence of Famennian and Lower Carboniferous age, composed of sandstones, shales, marls, and limestones, with a total thickness of

about 250 m. The coal-bearing deposits are of Lower and partly Middle Carboniferous age (in the opinion of some geologists, younger, up to Permian) and consist of sandstones, siltstones, argillites, and coal seams with a total thickness of about 4000 m.

The coal-bearing deposits are divided into seven formations (from bottom to top): the Akkuduk, Ashlyarik, Karaganda, Supra-Karaganda, Dolinka, Tentek, and Shakhan formations, of which four contain coal seams of workable thickness and are productive. The closely associated Ashlyarik and Karaganda formations together contain 30–40 workable coal seams, while the Dolinka and Tentek formations contain 22–30. The average thickness of the coal seams is 1–2 m; individual seams reach 5–10 m.

The Devonian and Carboniferous deposits are folded, complicated by numerous faults.

On the denuded surface of the Paleozoic there lies transgressively a unit of Mesozoic (Jurassic) deposits, represented by weakly cemented sandstones, conglomerates, argillites, and interbeds of brown coals. The Mesozoic deposits are distributed in the eastern and central parts of the basin, where in places they reach a thickness of up to 700 m. Their dislocation is insignificant: gentle waviness predominates, passing locally into low-amplitude folds; the ruptural disturbances observed in the Mikhailovsky brown-coal quarry and encountered by exploratory boreholes are weakly developed.

On the eroded surface of the Paleozoic and Mesozoic lie horizontally Tertiary clays and sands. In the eastern and central parts of the basin they occur as small patches, chiefly along river valleys, with a thickness rarely exceeding 10 m. In the western part of the basin they are widely distributed, and their thickness reaches 70–80 m.

Quaternary formations, represented by sandy-clayey rocks, within the basin cover all older geological formations as a continuous mantle. The thickness of the Quaternary rocks is usually 5–10 m; in the western part of the basin, within the Churubay-Nura district, owing to the alluvial deposits of the valley of the Churubay-Nura River, their thickness increases to 20–35 m.

The dimensions of the Karaganda Basin are conventionally determined by the outcrops of the lower boundary of the Akkuduk Formation, with which the coal-bearing deposits begin. The length of the basin from west to east is 100 km, its width 32–40 km, and its area about 3000 km². In the east the Karaganda syncline does not close and extends as a narrow strip in an ENE direction along the Ashchi-Su River for 150–180 km; the eastern continuation of the basin contains no coal.

On the west the basin is cut off by the meridional Tentek reverse fault, which brings rocks of the Lower and Middle Devonian into contact with the coal-bearing sequence; the reverse fault dips westward, and its amplitude is 3000–5000 m. Along the southern boundary of the basin there runs the large Dzhalair, or Dzhartas, overthrust, with a broad zone of apophysal faults. The overthrust is traced far beyond the limits of the basin. It has produced the very complex structure of the entire southern margin of the basin, characterized by steep dips of the rocks, broken by numerous faults. The strike of these folds and faults is most often latitudinal, parallel to the overthrust and to the boundary of the basin. The northern margin of the basin is relatively “quiet,” with gentle (15–30°) dips of the rocks predominating.

Within the basin three large troughs are distinguished, approximately equal to one another in area: the Churubay-Nura, Karaganda, and Verkhne-Sokur troughs, separated from one another by meridional uplifts.

The first two troughs are separated by the Alabas uplift; the Upper Sokur trough is separated from the rest of the basin by the Maikuduk uplift.

The easternmost of these—the Upper Sokur trough—has been very poorly studied, since it is covered by a blanket of Mesozoic deposits reaching a thickness of up to 700 m. Judging from data from boreholes drilled recently, the Carboniferous deposits of the trough are represented by the lower parts of the coal-bearing deposits. Its southern limb, free of the Mesozoic cover, is very strongly dislocated.

The Karaganda trough is situated in the central part of the basin. It has steep southeastern and southwestern limbs, a very steep dip of the southern limb, and a gentle plunge of the northern limb, which has been less affected than the others by faults. The southern limb is strongly corrugated by folds and complicated by numerous ruptures.

The Churubai-Nura trough is a complex asymmetric brachysynclinal fold, narrowing northward and elongated in the meridional direction. Its length is about 60 km, and its width in the middle part is 25 km. The southern and western limbs of the trough have steep, sometimes vertical, dips.

Because of the proximity of the Dzhalair thrust, the southern limb is strongly complicated by additional folds and numerous faults. Both the folds and the faults have a strike parallel to the margin of the trough and to the Dzhalair thrust. In most of these faults the displacers dip southward, and the southern blocks are thrust over the northern ones. The strong disturbance considerably reduces the industrial value of this area.

The proximity of the Tentek reverse fault has had a weaker effect on the western limb, which has almost no faults. The eastern limb of the trough in its northern part has dip angles of 40–45°; southward the dip gradually flattens to 10–15°. Likewise, from north to south the intensity of the limb’s fault tectonics increases. The dip of the northern limb is 35–45°.

The plunge of all the limbs of the trough to depth rapidly flattens, as a result of which its entire central part has a very gentle, undulating occurrence. Owing to this, second-order brachysynclinal folds were formed; the largest of them—the Dolinka and Tentek synclines—are located in the northern half of the trough.

The Dolinka syncline, composed of rocks of the Dolinka suite, has an almost meridional strike and is complicated by a fairly large number of small folds and faults. Its northwestern part, adjoining the Churubai-Nura reverse fault, is the most disturbed.

The Tentek syncline is composed of the uppermost suites of the basin’s Carboniferous deposits—the Dolinka, Tentek, and Shakhan suites. The western limb of the fold has a steep dip; the northern and especially the southern limbs plunge gently, at 5–45°, and are comparatively weakly disturbed.

South of the Tentek and Dolinka synclines, separated from the latter by a latitudinal uplift, there are two more small brachysynclinal folds: the Karagot (western) and Dzhaimin folds, composed of rocks of the Dolinka suite (Fig. 1).

Several opinions exist on the question of the formation of the tectonic structures of the Karaganda Basin.

N. G. Kassin saw the principal feature of the general structural plan of Central Kazakhstan in the existence of large ancient rigid blocks (platforms), bordered by narrow geosynclines developing between them and having the character of intermontane depressions or downwarps, representing belts of folding or faults. A second feature is—

there is a sharp discordance between the general plan of the Caledonian and Hercynian structures, in places amounting almost to perpendicular intersection.

The Karaganda depression, in his opinion, developed within the limits of a platform. During the period of Hercynian tectogenesis, its rigid basement, consisting of ancient Paleozoic and Precambrian rocks, not being capable of folding, was subjected to fracturing and displacements along the fractures. The Devonian–Carboniferous deposits at that time were gathered into folds and underwent rupture dislocations. The intersecting strikes of the Caledonian and Hercynian folds led to the formation of brachifold structures in the Devonian–Carboniferous strata, a process also promoted by block movements of the basement.

A fundamentally different scheme for the tectonic structure of Central Kazakhstan is proposed by N. S. Shatsky. He regards Central Kazakhstan as a geosynclinal region, divided into large synclines and anticlines whose outlines changed over time. N. S. Shatsky denies any influence of the platform on the orientation of folded structures and believes that the major depressions are confined to zones of virgation. The formation of these depressions is determined by the deep structure of the earth’s crust; N. S. Shatsky rejects N. G. Kassin’s “belts of crumpling” or “fault zones.” He replaces the superposition of two mutually intersecting Caledonian and Hercynian fold systems with a primary transverse type of structure.

Other existing views on the formation of tectonic structures in Central Kazakhstan merely supplement and somewhat modify the theories set out above.

In all works on the tectonics of Central Kazakhstan there is agreement that, during the period of Hercynian tectogenesis, the Precambrian and ancient Paleozoic basement underwent block movements that created tangential pressures in the Devonian–Carboniferous strata.

The structures of the coal-bearing strata of the Karaganda Basin were formed as a result of strong tangential pressure from the south, from the side of the Tekturmas Caledonian structures and of inherited meridional faults and uplifts of the basement, which likewise caused tangential pressures in the Devonian–Carboniferous strata, but already of local significance.

These local pressures complicated the dislocated nature of the basin, preventing it from assuming a strictly parallel orientation, as is the case in the Prisalaïr belt of Kuzbass. The creation of complex structures was also promoted by the uneven outline of the basin margin formed by ancient blocks, which, as N. G. Kassin wrote, “often served as guides for dislocations, sometimes being in contradiction with the acting forces.”

A. A. Petrenko and several other geologists believe that at first the basin was a single large brachysyncline with a latitudinal strike of its long axis, and that at the end of Hercynian tectogenesis the Alabas and Maikuduk uplifts arose, creating within the basin the Churubai-Nura, Karaganda, and Verkhnesokur troughs.

One should agree with this interpretation of the history of formation of the basin structure, since the later uplift of the Alabas anticline is confirmed by a uniform increase in the degree of coal metamorphism from east to west and from north to south, independent of the present structural elements of the basin (though these data require verification). This indicates that the area corresponding to the Alabas anticline, during the period of deposition of the productive strata, did not rise above the rest of the basin.

Data on the metamorphism of the coals also indicate that the southern and western parts of the basin underwent the deepest subsidence. In view of the fact that nearer the western boundary of the basin the degree of coal metamorphism begins to decrease, it may be assumed that the original boundary of the basin could not have been displaced far to the west. On the contrary, the increase in the degree of coal metamorphism toward the southern boundary of the basin indicates that originally the boundary lay somewhere considerably south of the present one.

As already stated above, detailed or preliminary exploration by core drilling has been carried out over a considerable part of the area of the Churubai-Nura trough. On the basis of the data from this exploration, it appears possible to identify the principal types of fault disturbances occurring here and the nature of their distribution on folded structures.

The eastern limb of the trough is at the same time the western limb of the Alabas uplift. Its strike is 335–340°. The northern half of the limb dips at an angle of 30–45° and gradually flattens from north to south. Almost no fault disturbances were detected by the exploration. Of those established, a pair of transverse ones are noted, having a strike at an azimuth of 50–60°, a dip at an angle of 70–80° to the south, and a displacement amplitude of about 100 m. There are somewhat more conformable thrust faults, with amplitudes up to 25 m and insignificant strike length.

The southern continuation of the eastern limb is characterized by considerable dislocation, expressed mainly by fault disturbances. The number and dimensions of the disturbances increase from north to south. The folding, too, becomes more intense toward the south, although it still remains slight and, in character, close to undulation. The eastern limb has a strike of 310–330° and in the south is joined with the southern limb of the trough, which has a strike of 250°. The faults are conformable thrust faults that break this area into a system of wedge-shaped blocks. The strike of the faults lies within the range 270–310°; their most latitudinal values are confined to the southern part. The dip of the rocks in this part of the trough is gentle and, if deviations due to the undulatory character of the bedding are not counted, amounts to 12–15°. The fault planes dip at 30–40° (Fig. 2). A clear adaptation of some faults is observed

Fig. 2. Character of tectonic faults in the southern part of the eastern limb of the Churubai-Nura trough.

to folds of the sequence; if the rocks change their strike or dip, then the direction of the fault planes changes correspondingly (Fig. 3). The apparent magnitude of block displacements in thrust faults (measurements were made on vertical sections cut across the strike of the sequence) is commonly 150–300 m, and in the largest ones 700–900 m.

Undoubtedly there must be many small faults in the area. This is indicated by observational data from the mine workings of mines Nos. 1, 2, 4, and 6/7 of the Churubai-Nura district, as well as from mines of the Karaganda district. But such faults are poorly detected by drilling exploration (faults with an amplitude of less than 50 m in areas with undulating bedding—

by the beds is detected only in those cases where they pass through boreholes), which creates the impression that there are fewer of them than of the large ones. Each fault is usually accompanied by smaller faults developed along its flanks. As already reported, almost all the faults here are concordant reverse faults. Only the small faults situated between the large ones sometimes represent other types—discordant reverse faults, normal faults, and thrusts.

Fig. 3. The phenomenon of tectonic faults adjusting to the beds of the sequence in the southern part of the eastern limb of the Churubai-Nura trough.

The tectonics of the northern and southern limbs of the Churubai-Nura trough, composed of the productive deposits of the Karaganda and Ashlyarik formations, has been established only in the most general outlines, owing to the fact that the northern limb has hardly been explored, while the southern limb is so tectonically complex (mainly because of fault disturbances) that it has not yet been possible to determine the nature of its structure. The general features of the tectonics were noted above. The tectonics of the Karagoga and Dzhaimin synclines is also poorly known.

The Dolinskaya syncline has a gentle (usually up to 20°), undulating occurrence of rocks with a meridional strike. Initially, the Dolinskaya syncline and the Tentek syncline constituted a single brachysynclinal fold of complex form, but subsequently it was split into two synclines by the Churubai-Nura reverse fault. The latter is one of the largest disjunctive disturbances in the inner part of the Karaganda Basin. From south to north it cuts almost meridionally across the entire Churubai-Nura trough. Its maximum amplitude near the central part of the Dolinskaya syncline reaches 1200–1500 m. The dip of the fault plane is westward at an angle of 30–40° (Fig. 4).

Fig. 4. Churubai-Nura reverse fault in the central part of the Dolinskaya syncline.

The Dolinskaya syncline is disturbed unevenly. The calmest part is the southern part of the eastern limb, where construction of mines on the seams of the Dolinskaya suite began. Within the mine workings, one transverse and two longitudinal faults have so far been detected. The transverse fault has a latitudinal strike; the fault plane dips southward at an angle of 70–80°, and the displacement amplitude is 40–60 m. Near the fault there is a broad (up to 30–40 m) zone of crushed rocks.

The longitudinal faults belong to the type of normal faults; their strike is 15°, their dip is westward at an angle of 60°, and their amplitude is 2–6 m. In addition to those indicated, in this part of the syncline exploration has established 4–5 longitudinal concordant reverse faults with westward dip and an amplitude of 50–70 m.

The western limb of the southern part of the Dolinskaya syncline is considerably disturbed. Longitudinal (meridional) faults predominate, but there are also several diagonal ones. Most of the longitudinal faults have an easterly dip; some of them have a westerly dip. The former are concordant reverse faults, the latter discordant. The displacement amplitude is most often 40–70 m, and the dip of the fault planes is 50–60°. The extent along strike of some of these faults, especially the concordant reverse faults, is fairly large—2–3 km. Discordant reverse faults almost always occur together with concordant ones, creating block displacements of a horst type (Fig. 5).

Fig. 5. Block structure formed by diagonal concordant and discordant reverse faults on the western limb of the Dolinskaya syncline.

The most complex tectonics of the Dolinskaya syncline is observed in its central part, where small folding of the waviness type and fault disturbances are strongly developed. The latter are characterized by latitudinal strikes and steep dips. Because the strikes of the faults coincide with the direction of the exploration lines, their character has been poorly studied. The map of the coal-seam outcrops beneath the cover deposits gives grounds to suppose that the transverse faults have northern dips and that their northern blocks are uplifted relative to the southern ones. Most likely these faults should be assigned to the type of strike-slip faults. Without such an interpretation of the character of the disturbances it is difficult to explain the considerable eastward displacements of the axis of the southern part of the syncline (Fig. 1).

The northern part of the Dolinskaya syncline is represented only by the eastern limb, since the western one is cut off by the Churubai-Nura thrust fault. The predominant faults here are longitudinal, with meridional strikes. In the southern part of this area the disturbances pass into diagonal ones, with a strike of 300–320°. Some of them probably pass into the eastern limb of the Churubai-Nura trough. In the very northern part of the syncline the disturbances also deviate from a meridional strike and, at an azimuth of 300°, cut across the axis of the syncline, and then the northwestern limb of the Churubai-Nura trough, which here has a strike of 50° (Fig. 1). The main part of the longitudinal faults dips westward at an angle of 45–55°, thus being concordant thrust faults.

These faults in the area have the greatest dimensions both in length of strike and in displacement amplitude, which for some of them reaches 400 m. By such faults the area is divided into large blocks, the boundaries of which are usually taken as the boundaries of mine fields. Among the diagonal faults, a considerable part has easterly dips (45–60°). These faults, which by type are discordant thrust faults, almost never attain an amplitude of more than 150 m (Fig. 4). There are very few transverse faults in this area; they are small and poorly studied.

In the Tentek syncline the eastern limb is the more complex, probably because of its proximity to the Churubai-Nura thrust fault. The eastern limb is cut by several large transverse faults branching off from the Churubai-Nura thrust fault. They have displacement amplitudes of 300–500 m and a steep dip southward of 60–80°. From these faults extend smaller faults—transverse and diagonal, of the thrust-fault type.

The southern limb of the syncline, which has a wavy bedding of the rocks, is less disturbed than other areas. Drilling exploration has not revealed major faults. Small faults of 1–2 m, in individual cases up to 25 m, were recorded by exploratory mine workings.

The western limb of the syncline has almost no fault disturbances, despite the fact that the Tentek thrust fault passes near it, giving the limb steep to vertical angles of plunge. The southwestern part of the syncline is somewhat more disturbed by a series of step-like thrust faults of western dip. The northern and northwestern parts of the syncline have been poorly explored; according to the available materials, fault disturbances are significantly developed in this part, with concordant thrust faults predominating among them.

Thus, by geological-exploration work carried out in the western part of the Karaganda Basin, the general structure of the Churubai-Nura trough and the character of the tectonics of its individual structural elements—the limbs and internal brachysynclines—have been established. A significant

part of the Churubai-Nura trough has now been explored in detail (the eastern limb of the trough, the Dolinka and, partly, the Tentek synclines), and therefore the tectonics have been studied with a completeness that makes it possible to design mines here.

The available exploration material makes it possible to outline certain regularities in the distribution of folds and faults, their interrelationship, and the factors that determined their formation. The principal ones are as follows.

1. The tectonics of the coal-bearing deposits of the Churubai-Nura trough were determined by southern and western pressures.

The pressure from the south was the more powerful; it formed the Dzhalair thrust and brought the southern limb into steep dip, tearing it by numerous fractures parallel to the thrust. Along these fractures, which dip to the south, the southern blocks were thrust over the northern ones. The number and dimensions of these fractures decrease from south to north. In the northern half of the trough these fractures are almost absent.

Western pressure also played a considerable role in the formation of folded and fault dislocations. It formed the Tentek reverse fault, which cut off the western limb of the trough, brought the western limb of the Tentek syncline into steep dip, and broke the southwestern part of the trough into imbricate blocks. The Churubai-Nura reverse fault and many other faults likewise owe their origin to western pressure.

1. Only some of the largest faults are directly connected with fractures in the basement. These include the Dzhalair thrust, the Tentek reverse fault, possibly the Churubai-Nura reverse fault, and some others. The entire remaining mass of faults arose in connection with the folding of the Devonian–Carboniferous sequence and therefore is in close interrelation with the folded forms.

2. All faults may be divided into three groups, depending on the relation of their strike to the strike of the rocks: longitudinal, diagonal, and transverse.

The predominant part of all faults established by exploration belongs to longitudinal faults, which cut the sequence at an angle of less than 30°. Most such faults are conformable reverse faults.

Faults that cut the rocks along strike at an angle close to 45° are less common. These faults, called diagonal, are also often conformable reverse faults.

Both longitudinal and diagonal faults are sometimes unconformable with the rock sequence; such faults are usually represented by unconformable reverse faults, more rarely by normal faults. Far fewer transverse faults, compared with longitudinal and diagonal ones, have been revealed by exploration; these always have a steep, almost vertical, dip of the fault plane. In vertical sections, the fault planes of diagonal longitudinal disturbances usually form an angle with the bedding of the coal-bearing rocks close to 30°. Individual faults curve in accordance with the bends of the sequence. The surfaces of the fault planes are more often uneven and wavy.

1. Major faults are usually accompanied by smaller ones. In this connection, areas around major faults are strongly disturbed. Thus, the Dolinka and Tentek synclines are considerably more strongly disturbed in the areas located near the Churubai-Nura reverse fault. Isolated faults are almost never encountered.

2. Disturbance of the rocks usually increases with an increase in the angle at which a fault intersects the bedding of the rocks. Therefore, often, along large longitudinal conformable reverse faults, the rocks in the walls of the fault are not crumpled, whereas even an insignificant transverse fault is accompanied by a wide zone of crumpled rocks.

1. The occurrence of the rocks is characterized by undulation. Undulation is more strongly expressed where the dip is gentle. Where the rocks dip steeply (the northern part of the eastern limb of the Churubai-Nura trough, the western limb of the Tentek syncline), undulation has not been noted by exploration.

It should be observed, however, that the study of the tectonics of mine fields on the basis of detailed exploration materials is incomplete and cannot ensure uninterrupted operation of the mines throughout the entire period of their exploitation. This is explained by the fact that small faults are not detected by exploratory boreholes, and, when numerous, they seriously hinder mining operations. Such a situation occurs, for example, in the Saran mines of the basin. Therefore the task of studying the tectonics of mine fields should not be limited to compiling seam maps and geological sections along exploration lines. It must consist in preparing a forecast of minor dislocation and jointing (cleavage). The forecast must include an assessment of the degree of dislocation, i.e., the number of faults per unit area, the dimensions of the faults, their type, orientation, the degree of crumpling of the rocks, and information on the orientation of cleavage planes, their frequency, and the degree to which they are expressed.

A forecast is possible only on the basis of a detailed analysis of both exploration and mine tectonic material. Mine material is especially valuable for these purposes. The analysis must consist in identifying the interrelations among folds, fault forms, and cleavage.

For carrying out the research topic “Tectonics of the western part of the Karaganda Basin,” the following methodology is proposed.

1. Collection and study of all exploration material; recompilation of individual areas of geological maps or sections if they were compiled unconvincingly or if their interpretation, acceptable for individual mine fields, is in contradiction with geological constructions made for larger areas. In carrying out this part of the work, it is necessary to check especially carefully to what extent the factual material corresponds to, or contradicts, our conception of the role of southern and western pressures in the formation of the tectonics of the Churubai-Nura trough.

2. Description of fold forms (limbs, hinge zone, axial lines and axial planes) and establishment of the relationships of these elements between the principal and subsidiary folds. Description of faults (strike, dip, amplitude), their relationship to folds, and the relationship of faults to one another.

3. Observation of tectonics in the workings of operating and newly constructed mines, as well as in exploratory mines. Sketching and photographing, with the aim of establishing the condition of the rocks on the sides of faults and the character of the fault planes. It is especially necessary to pay attention to the study of small faults and small folds not detected during detailed exploration. Establishment of the connection between small-scale and large-scale (on the scale of a mine field) tectonics. Correction of exploration data by means of mine-documentation materials; clarification of the causes that led to errors in the interpretation of exploration data.

4. Observation of the character of slickenside striations on the surfaces of fault planes and measurements of their orientation. On the basis of oriented striations on fault planes, establishment of the true direction of movement of blocks in faults.

5. Study in mines of the jointing of coal and enclosing rocks by means of measurements and photography, with the aim of determining the fractures, their spatial orientation, and their relation to folds and faults.

On the basis of the materials collected, a map of fracturing should be compiled. The deficiency in underground mapping will be supplemented by observations on core, using the method proposed by I. A. Ocheretenko. The essence of the method consists in determining, from the core, the elements of occurrence of fractures in relation to the elements of occurrence of the bedding of the rocks, which makes it possible to plot fracturing on the geological map (measurements are made with a special overlay).

This method of observing fracturing is not distinguished by great accuracy, but, because of the possibility of making mass observations, it undoubtedly deserves attention. In addition to helping in the deciphering of tectonics, our observations of fracturing should prove useful for selecting the direction of mine workings and for the use of mining machines in coal cutting.

1. Examination of the core and geological descriptions of old boreholes in order to determine the character and magnitude of the zone of rock crumpling along the flanks of faults of various types and sizes.

2. Since within the Churubai-Nura trough there are few mines and comparatively few observations of tectonics will be obtained directly in mines, the established regularities will be checked against the extensive material from exploration and mine documentation of the neighboring Saransk area.

3. As a result of this work it is also proposed to provide an assessment of the tectonics of the areas of the western part of the Karaganda Basin from the standpoint of the complexity of their exploitation. In addition, proceeding from the practice of the construction and operation of mines in the Karaganda and other basins, considerations and recommendations will be set forth for specific areas of the district under study concerning the nature and scope of stripping and operational exploration.

Trest “Kazakhuglegeologiya”