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Table 1.
Types of landslides of quarry pit edges and benches (according to P. N. Panyukov)
Types of
Characteristics of types
Main conditions of landslides
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landslides
Simple: the
actual landslides
The sliding surface has a complex shape:
the upper part is vertical, the middle and
lower parts are curved with a reverse fall
(towards the array) on the lower segment
An array of non-cemented rocks
slide off
Displacement of mined blocks and
bundles of rocks of the escarpment massif
on the weakening surfaces falling towards
the escarpment
Cutting the slopes of the
weakening surfaces falling in the
direction of the workings
landslides-slip
(complex slip)
The same, but the sliding surface passes
in the direction of weakening only in the
upper part, the lower part of it crosses the
surface of weakening at different angles
and goes into the slope at its base
The fall of the attenuation surface
in the direction of the workings at
an angle greater than the angle of
the pit edge slope
Complex:
landslides of
extrusion
The landslide process is preceded and
accompanied by plastic squeezing of
weak clay rocks. Sliding occurs on a
plastically deformable base
The presence of weak clay easily
squeezed rocks in the massif or at
the base of the slope
landslides
The landslide process is preceded and
accompanied by the melting of the rocks
of the base or lower part of the slope.
Sliding occurs on the swollen rock
The presence of rocks at the base
or in the lower part of the slope
that can float under the influence
of filtration pressure and vibration
landslides
subsidence
The landslide process is preceded and
accompanied
by
compaction
(subsidence), and sometimes subsidence
of the rocks of the slope, which occur
under the influence of vibration and
moisture, or both
The presence of loose-folded or
subsident rocks in the section of
the slope
For simple landslides, the sliding surface consists of two parts: the upper one is vertical and
the lower one is complex-curved. Simple landslides, as a rule, are characteristic of non-cemented
(sandy – clay) rocks in the case of evenly distributed and intense fracturing, they are also capable of
producing deformations such as simple landslides. As for complex landslides, they usually do not
show a expressed sliding surface [2, 3].
As a result of mapping, it was found that the axis of the Besopan formation, whose rocks
make up the synclinal formation, coincides with the long axis of the quarry. From the North and
from the South, the syncline is bounded by the structural and southern faults. They have a
sublatitudinal strike and fall at an angle of 80-85° to the South. Along the strike, the faults break up
into a number of subparallel tectonic seams and are represented by shale, melonitized rocks; the
presence of friction clay is noted. The north-eastern ruptures are represented by a series of
successive tectonic seams with a total thickness of 70-80m. Tectonic breccia with quartz-chlorite-
calcite cement is observed in some parts of the seams.
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The geomechanical state of the massif depends on changes in the structure of the
environment, deformation of the blocks, and their movement under the influence of gravitational,
tectonic, and intense seismic impacts of natural and man-made origin. As you know, the stability of
the general angles of inclination of the pit edges is determined by the complex of engineering-
geological, technological, and hydrological factors and is the main indicator that allows you to
significantly reduce the overburden ratio and significantly improve the technical and economic
indicators of the development of deposits on deep horizons [1-3].
According to the reports, the "M" quarry is located within four large tectonic blocks:
Northern (C), Central (C), Southern (S) and Western (3), separated by faults of the I and II orders of
the meridional, submeridional, latitudinal and north-eastern strike.
The central block covers the most significant area of the "M" quarry and is bounded on the
south by the Southern Fault, and on the North by the North-Eastern One. The southern fault has
modern geodynamic activity, as indicated by the gully network formed as a result of quarry
development. At the North-eastern fault, the sublatitudinal strike linaments are traced, emphasized
by sharp knee-shaped bends of the river network and fourth-order watercourses. In the west, the
fault articulates with the Southern fault of the sublatitudinal strike. In the Central Block, there is a
large discontinuity of the latitudinal strike, which divides it into two approximately equal parts. In
the relief, this violation is expressed by rectilinear ledges and knee-shaped bends of watercourses of
the fourth order. Here, a network of discontinuous disturbances of the north-west direction is
revealed, expressed in the relief by narrow over-buried valleys of ravines. They appear to be the
cracks of the cliff.
The northern block is probably in the tensest state than the other blocks of the district. Here,
a series of discontinuous disturbances of the sublatitudinal northeastern and submeridional
directions is observed. The Northern fault appears to be a major thrust with the displacement plane
falling to the Northwest. In the Northern Block, a system of North-West separation cracks is also
clearly revealed. The length of the cracks in some cases reaches 2 km.
The southern block is divided by a fault of the second order into two: Southern - I and
Southern - 2 (Fig. 2.1). Within its limits, most of the seismic dislocations of the northwestern strike
can be traced, which are currently blocked by the dumps of the "M"quarry. However, the
southernmost of them are also recorded in the images of the 1982 flight, which indicates the current
geodynamic activity of seismic dislocations.
The Eastern block is separated from the Northern, Central and Southern by the zone of the
Eastern Fault and within its limits there are discontinuous violations of the latitudinal, north-eastern
and north-western strike, and covers the eastern part of the area of the "M" quarry, where the
articulation of these faults of the I and II orders occurs, thereby causing intense disturbance of the
Eastern side.
Currently, quite detailed classifications of landslide cracks have been developed [4-8].
However, all of them are not universal and do not cover cracks of the type, for example,
stratification, drying, weathering, etc. Therefore, the most appropriate way to do this is to map the
cracks.
In the Western Block, a series of large discontinuous faults of the submeridional strike is
distinguished, dividing it into a number of segments. Small discontinuous faults of the North-West
Strike are also visible here.
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