Сollision deformations of the Dnieper-Donets Depression. Article 1. Tectonics of the articulation zone with the Donets folding structure

The article is the first part of a trilogy devoted to the study of post-rift deformations of the riftogenic structure of the Dnieper-Donets paleorift. The mechanisms of collision warping of the horizons of the sedimentary cover of the southeastern part of the Dnieper-Donets depression are considered. According to the previous mapping data, the tectonic deformations of the sedimentary cover were controlled by systems of faults of the north, north-west, and south-east vergence. The lattices of tectonites of the Hercynian, Lamaric, and Attic generations determine the specific “cross-thrust” structure of pushing. Overthrusts and linear folding of three generations permeate the sedimentary sequence of the transition zone from east to west for hundreds of kilometers within the eastern part of Izyumsky paleorift segment. The analytical base of the research was the materials of geological mapping of the zone of the junction of the depression with the Donets fold structure. Using field definitions of the tectonite vergency of the Hercynian, Laramide and Attic phases of tectogenesis, the original method of reconstruction of tectonic deformation fields and tectonophysics analysis of structures, collision deformations of the sedimentary cover of the south-eastern part of the Dnieper-Donets paleorift are studied. The tectonophysical analysis of tectonites of different ages indicates that together they control the cover-thrust and folded deformations of the riftogenic structure. Overthrusts and linear reverse-folding of three generations form the West-Donetsk integumentary-folding region, within which a segment of the same name tectonic thrust is distinguished. By pushing the system of repeatedly deformed, crushed into folds of geomass sedimentary rocks on weakly deployed syneclise deposits, the riftogenic structure of the south-eastern part of the basin is completely destroyed. The structural-tectonic framework of the allochthone, pushed from the side of the Donets structure, is composed of dynamically conjugated lattices of Hercynian, Laramide, and Attic tectonites. They control the echelon backstage of linear reverse-folds, tectonic plate-covers of transverse extrusion of sedimentary geomass from axial to airborne zones and folded covers of longitudinal thrust from the south-east. The riftogenic structure of the transition zone between the Dnieper-Donets basin and the Donets folded structure was completely destroyed by deformations of three generations of platform activation. The dynamically coupled tectonite lattice, the overlays, and the folded zones of the Hercynian, Laramide, and Attic generations jointly form the West-Donets fold-fold region within its boundaries. The main tectonic element of the area is the eponymous subregional tectonic thrust segment. The central structural zone is Veliko-Kamyshevakhskaya, Novotroitskaya, Druzhkovsko-Konstantinovskaya and Main anticlines. The central zone divides the body of the segment into two tectonic regions according to the tectonic style and intensity of deformation of the sedimentary sequence. The northern part is occupied by the Luhansk-Kamyshevakhsky region of the rocky-layered linear folding of the thrust, and the southern part is the Kalmius-Toretsky region of scaly tectonic covers.

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Tectonic inversion of the Dnieper-Donets basin. Part 1. Collizion tectonics of the Western-Donets graben

Geology Geography Ecology ◽

10.26565/2410-7360-2020-52-01 ◽

2020 ◽

Keyword(s):

Transition Zone ◽

Sedimentary Cover ◽

Donets Basin ◽

Tectonic Deformation ◽

Sedimentary Sequence ◽

Heterogeneous Distribution ◽

Three Generations ◽

The North ◽

Thrust Front ◽

Folded Structure

Formulation of the problem. New results of tectonophysical studies of the structural-kinematic evolution of the Earth's crust of Dnieper-Donets paleorift at the collision stage are presented in the paper. The subject of research is a complex of deformation structures that complicate the sedimentary cover in the transitional zone with Donets folded structure. Review of previous publications and studies. According to new mapping data, tectonic deformations of the sedimentary cover were controlled by systems of faults of the north, northwest, and southeast vergence. The lattices of the Hercynian, Lamaric, and Attic tectonites determine the specific “cross-thrust” structure of pushing. Due to the heterogeneous distribution of deformations of different ages, the stratigraphic volume of the sedimentary sequence varies in area from the Pliocene-Anthropogenic to the Mesozoic-Cenozoic. Overthrusts and linear folding of three generations permeate the sedimentary sequence of the transition zone from east to west for hundreds of kilometers within the eastern part of Izyumsky paleorift segment. Methods. Using the original method of tectonic deformation fields’ reconstruction and tectonophysics analysis of structures, collision deformations of the platform sedimentary cover of the southeastern part of Dnieper-Donets depression are studied. The materials of geological mapping of the transition zone and instrumental definitions of the vergence of the Hercynian, Laramian, and Attic faults constituted the analytical base of tectonophysical studies. Results. In the transition zone, West-Donets segment of the tectonic wedging, which completely destroys the riftogenic structure in the southeast of the basin was identified. It was formed as a result of a thrust on the syneclise autochthon repeatedly deformed, crumpled into the folds of geomass from the western slopes of Donets folded structure. It consists of structural ensembles of linear thrust folds, tectonic covers of transverse, pushing of sedimentary geomas from axial to onboard zones, and folded covers of longitudinal thrust. The thrust covers and folds of allochthon end in the depression with scaly compression fans formed at the ends of the main thrusts. In the thrust front of West Donets segment, a geodynamic discharge strip was diagnosed, where structural zones of displacement of geomass were formed. On the north-eastern flank of the thrust front they are represented by large linear anticlinal zones of the so-called “open Paleozoic structures”, such as Torsko-Drobishevsk, North-Donets, Matrossko-Toshkovsk zones, and on the southwestern - Petrovsky-Novotroitsk zone of reverse-folds. The structural peak of the West-Donets segment is the tectonic node of thrusts and strike-slips of three generations, localized in the joint area of the central and southern structural branches of the axial salt-dome folding. Scientific novelty and practical significance. The current regional tectonic scheme has been revised on the conceptual foundations of dynamic geotectonics. It is shown that the riftogenic structure of the transition zone at the collision stage of evolution was completely destroyed by deformations of three generations. Lattice of tectonites, thrust cover and uplift folding zones of the Hercynian, Laramian, and Attic generations together form West-Donets cover-fold region within it. The main tectonic element of the region is the segment of the tectonic wedging of the same name. By the nature of the structure in its northern part, Lugansk-Kamyshevakhsky district is distinguished by a link echelon of linear folding, and in the south by Kalmius-Toretsky region of tectonic thrust cover. West Donets segment is an important component of the structural-tectonic frame of the sedimentary cover, which determines the modern transverse tectonic segmentation of the paleorift.

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Collision deformations of the Dnieper-Donets Depression Article 3. Geodynamic model of tectonic inversion

Geology and Geochemistry of Combustible Minerals ◽

10.15407/ggcm2020.01.040 ◽

2020 ◽

Vol 1 (182) ◽

pp. 40-51

Author(s):

Оleksiy BARTASHCHUK

Keyword(s):

Regional Scale ◽

Original Method ◽

Donets Basin ◽

Horizontal Shear ◽

The South ◽

The West ◽

Geodynamic Model ◽

Late Mesozoic ◽

South Eastern ◽

Tectonic Inversion

The article concludes the trilogy on post-strip deformations of the Dnieper-Donets Basin. The results of tectonophysical analysis of collision deformations of the platform cover of the south-eastern part of the Dnieper-Donets Basin are summarized. Using the original method of reconstruction of stress and strain fields and tectonophysical analysis of geostructures, the system organization of inversion structural deformations of the Dnieper-Donets Basin and Donbass was studied. The tectonic inversion of the Dnieper-Donets Basin began in the Late Hercynian epoch in the situation of a general-plate collision under the influence of the inversion rise of the Donbas. Structural and kinematic analysis of deformations shows that the folds in the depression and linear anti- and synforms of the Donets Foldbelt were formed by the natural mechanism of longitudinal bending as a result of collisional warping of horizons in the geodynamic mode of transformation. In the late Mesozoic–Cenozoic inversion continued in the field of right-hand horizontal-shear deformations with a variable compressive component. This mode caused the advancing and pushing of sedimentary geomass from the Donets Foldbelt to the Hercynian neo-autochthonous and syneclise autochthonous of the South-Eastern Dnieper-Donets Basin. Due to the influence of the tectonic stamp of the Donets Foldbelt, the West Donets wedge-shaped segment was formed – the orocline of geomass tectonic wedging. Geodynamic bands of injection and displacement of sedimentary geomass were formed in the front of the invasion and in the axial zone of the orocline, where the main folded zones were formed. In Forland, at the ends of the main thrusts – “tectonic rails” of the wedging, an advanced scaly compression fan was formed. In the hinterland of the orocline, folded suture zones are formed by the roots of the covers of thrusting. The original geodynamic model of tectonic inversion provides for the destruction of the riftogenic structure in the Southeast of the Dnieper-Donets Basin by thrusting echelons of scaly covers and coulisses-articulated upliftt-folding. They compose a segment of the insertion of the geomasses of the Paleozoic cover into the territory of the West Donets Graben from the side of the Donets Foldbelt. The intrusion of the tectonic segment led to the formation of an inversion structure of a regional scale – the West Donets Cover-Folded Region.

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GEODYNAMICS

GEODYNAMICS ◽

10.23939/jgd2020.02.051 ◽

2020 ◽

Vol 2(29)2020 (2(29)) ◽

pp. 51-65

Author(s):

A. V. Bartashchuk ◽

◽

V. G. Suyarko ◽

Keyword(s):

Transition Zone ◽

Sedimentary Cover ◽

Central Zone ◽

Geological Mapping ◽

Donets Basin ◽

Evolutionary Stage ◽

The South ◽

Zone Formation ◽

The North ◽

Tectonic Style

Aim of the work is tectonophysical identify the totality of the deformation structures of the collisional evolutionary stage, which determine the tectonic style of the Transition Zone between Dnieper-Donets Basin and the Donbas Foldbelt. Methods. For the research, we used the author's technique for reconstructing the fields of tectonic deformations and tectonophysical analysis of geostructures. The analytical base of the research was made up of new materials of geological mapping of the territory of the transition zone between the Basin and the Foldbelt. Results. Inversion deformations of the Dnieper-Donets Paleorift were controlled by lattices of tectonites of regionally stable submeridional directions of movements. An analysis of structural patterns of tectonites indicates over the riftogenic faults of the basement in the sedimentary cover of the transition zone, echeloned stages of plumage are formed, composed of thrusts with a significant component of horizontal displacement. The tectonic style of the Transition Zone is determined by the pushing on the low dislocation autochthonous of the Basin of the repeatedly deformed, crumpled into the folds of sedimentary geomas from the Foldbelt. The allochthon structural and tectonic framework consists of thrusts, coulisse-jointed structural ensembles of thrusts, folded covers of transverse extrusion of geomas from axial to side zones, and folded covers of longitudinal thrust towards the depression. All together its form the Western Donets Cover-folded Region, the main structural element of which is the Segment of the Tectonic Wedging of geomass. The north-eastern flank of the Segment is formed by linear anticlinal zones - Torsky-Drobishivska, North-Donets, Matrossko-Toshkovska, south-western - Petrovsko-Novotroitska. The structural apex of the Segment is a tectonic junction at the ends of dynamically conjugated thrusts in the area of the joint of the salt-dome shafts of the axial part of the Basin. Scientific novelty. The tectonic inversion is responsible for the formation of three folded structural floors - the Herzinian, Laramian and Attic. According to the dynamically coupled lattice, a cover-folding system of tectonic thrusting was formed in them, which was first diagnosed as a Segment of Tectonic Wedging of geomas by the Donbas Foldbelt. On the basis of this, within the Transtition Zone, a Western-Donetsk cover-folded Region was separated, covering two tectonic areas in intensity and style of deformation of the sedimentary cover - Kalmius-Toretsky area of scaly covering in the southwestern part, which is limited to the South Donbass Melange Zone in the south, and the Lugansk-Kamyshuvakhsky area of the coulisse-jointed uplift-folding on the northeastern part, which from the north is limited by the low-folded Mesozoic-Cenozoic cover. They are separated by the Central Zone of Strike-slip control along the axial folded zone of large stage-jointed uplift-folds, which include Great-Kamyshuvakhska, Novotroitska, Druzhkovsko-Konstantinovska and Main anticlines. Practical significance. Based on the actual geo-mapping data, it is proved the riftogenic structure in the southeast of the Dnieper-Donets Paleorift is destroyed by folding at the stages of platform activation. Allocation of territory of the Western Donetsk Сover-folded Region allow to correct the scheme of tectonic zoning of the Dnieper-Donets Basin, which is the basis for modeling the geodynamics of the Transition Zone formation.

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IV.—On the South-Eastern Coalfield

Geological Magazine ◽

10.1017/s0016756800142712 ◽

1899 ◽

Vol 6 (11) ◽

pp. 501-505

Author(s):

W. Boyd Dawkins

Keyword(s):

British Association ◽

Total Thickness ◽

The South ◽

The West ◽

South Eastern ◽

The Rich

The discovery of a coalfield in 1890 at Dover, in a boring at the foot of Shakespeare Cliff, has been already brought before the British Association by the author at Cardiff in 1892, and is so well known that it is unnecessary to enter into details other than the following. The Carboniferous shales and sandstones contain twelve seams of coal, amounting to a total thickness of 23 feet 5 inches. These occur at a depth of 1,100 feet 6 inches below Ordnance datum, and have been penetrated to a depth of 1,064 feet 6 inches, or 2,177 feet 6 inches from the surface. They are identical, as I have shown elsewhere, with the rich and valuable coalfields of Somersetshire on the west, and of France and Belgium on the east

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Ritual under Change: Mongolian Influences on Horse Races and Mountain Divinity Worship in Tibet

Inner Asia ◽

10.1163/146481702793647506 ◽

2002 ◽

Vol 4 (2) ◽

pp. 361-373

Author(s):

Elke Studer

Keyword(s):

Seventeenth Century ◽

Central Government ◽

The Political ◽

The South ◽

The West ◽

Horse Race ◽

Autonomous Region ◽

South Eastern ◽

The North ◽

History Of

AbstractThe article outlines the Mongolian influences on the biggest horse race festival in Nagchu prefecture in the Tibetan Autonomous Region (TAR).Since old times these horse races have been closely linked to the worship of the local mountain deity by the patrilineal nomadic clans of the South-Eastern Changthang, the North Tibetan plain. In the seventeenth century the West Mongol chieftain Güüshi Khan shaped the history of Tibet. To support his political claims, he enlarged the horse race festival's size and scale, and had his troops compete in the different horse race and archery competitions in Nagchu. Since then, the winners of the big race are celebrated side by side with the political achievements and claims of the central government in power.

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On a Quartz-porphyry from the Lake District

Geological Magazine ◽

10.1017/s001675680010202x ◽

1924 ◽

Vol 61 (11) ◽

pp. 513-515 ◽

Cited By ~ 3

Author(s):

Sidney Melmore

Keyword(s):

Igneous Rock ◽

The Body ◽

Lake District ◽

The South ◽

The West ◽

Quartz Porphyry ◽

West Side ◽

South Side ◽

The Road

A Small quarry was opened about three years ago at Thwaite Head, which lies between the southern ends of Coniston Lake and Windermere. It is on the west side of the road between that hamlet and Hawkshead, and exposes a nearly vertical sill, 40 feet wide, running E.N.E.-W.S.W. in the Bannisdale slates. On the south side a series of joint-planes running parallel to the bedding of the slates and curving inwards at the top have split the igneous rock into flags, while in the body of the rock the jointing is much coarser, so that it is quarried in large blocks. Both the igneous rock and the slates are much decomposed and friable along the southern junction, and it is here a little galena is said to have been found when the quarry was first opened. This is not improbable, as the old Thwaite Head lead mine is situated not far off on the banks of Dale Park Beck.

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The dialect of Shahrud (Khalkhāl)

Bulletin of the School of Oriental and African Studies ◽

10.1017/s0041977x00076126 ◽

1959 ◽

Vol 22 (1) ◽

pp. 52-68 ◽

Cited By ~ 3

Author(s):

E. Yarshater

Keyword(s):

Magnetism and age of the Porteau Pluton, southern Coast Belt, British Columbia: evidence for tilt and translation

Canadian Journal of Earth Sciences ◽

10.1139/e95-033 ◽

1995 ◽

Vol 32 (4) ◽

pp. 380-392 ◽

Cited By ~ 12

Author(s):

E. Irving ◽

J. Baker ◽

N. Wright ◽

C. J. Yorath ◽

R. J. Enkin ◽

...

Keyword(s):

British Columbia ◽

North America ◽

Coercive Force ◽

The Body ◽

Canadian Cordillera ◽

Southern Coast ◽

The South ◽

The West ◽

Zircon Age ◽

Minimum Estimate

The Porteau Pluton is a variably foliated quartz diorite to granodiorite intrusion in the southern Coast Belt of the Canadian Cordillera (49.6°N, 123.2°W). 40Ar/39Ar ages are 95 ± 5 Ma from biotite and 101.5 ± 0.7 Ma from hornblende, which, together with an earlier U–Pb zircon age of 100 ± 2 Ma, indicate that the body was emplaced, uplifted, and cooled rapidly in mid-Cretaceous time. The rocks contain high coercive force (hard) remanent magnetizations with unblocking temperatures between 500 and 600 °C, close to those of Ar in hornblende, indicating that remanence was acquired at or close to the hornblende plateau age. The hard remanence directions have an elongate distribution, in agreement with the predictions of M.E. Beck regarding magnetization acquired during tilting, uplift, and cooling of plutons. No part of the distribution agrees with the direction expected from observations from rocks of mid-Cretaceous age from cratonic North America. The elongate distribution defines the axis of tilt (347° east of north) but not its direction; tilt could have been down toward the east or down toward the west. The former yields an inclination that is 29.0 ± 4.9° shallower than expected from cratonic observations, corresponding to a displacement from the south of 3200 ± 500 km. The latter reconstruction yields an inclination that is anomalously shallow by 14.8 ± 3.9°, corresponding to a displacement from the south of 1600 ± 400 km, which is a minimum estimate. It is argued, therefore, that the Porteau Pluton has undergone both tilt and displacement from the south by distances substantially in excess of 1000 km.

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Tectonic inversion of the Dnieper–Donetsk Basin. Part 2. Geodynamic situations and kinematic mechanism of riftogenic structure deformations

Geology Geography Ecology ◽

10.26565/2410-7360-2020-53-01 ◽

2020 ◽

Keyword(s):

Sedimentary Cover ◽

Kinematic Model ◽

Strike Slip ◽

The Body ◽

Donets Basin ◽

Donetsk Basin ◽

Kinematic Evolution ◽

Tectonic Inversion ◽

Reverse Thrust ◽

Kinematic Mechanism

Formulation of the problem. In the second part of the article, the geodynamic mode and the kinematic mechanism of destruction of the Dnieper–Donetsk Basin by tectonic movements of the Late Hercynian and Alpine stages of tectogenesis were studied. New results of tectonophysical studies of the structural–kinematic evolution of the Earth's crust of Dnieper–Donetsk Basin at the collision stage are presented. The subject of research is a complex of deformation structures that complicate the sedimentary cover in the transitional zone of with Donetsk Foldbelt. Review of previous publications and studies. Using instrumental definitions of tectonite vergence, data of reconstruction of stress fields and quantitative modeling of deformations, a original kinematic model of tectonic inversion of the Dnieper–Donetsk Basin was developed. Methods. Structural–kinematic analysis of the structural drawings of collisional deformation and tectonics structures was used for regional geotectonic studies. Results. Tectonic inversion of the Dnieper-Donetsk Basin and Donbass began at the Late Hercynian epoch as a result of collisional movements of the compression orogen on the outskirts of the Paleotethis. Tangential compression of the southwestern direction led to the formation of gentle tectonic faults in the sedimentary cover of the Western Donets Graben, along which a lattice of thrust faults was formed. For a set of extrusion of sedimentary rocks in the reverse–thrust mode from the axial super-compressed zone, tectonic transport of geomas took place in the direction of the zones of "geodynamic shadow" on the southern side. Collisional deformations of horizons by the mechanism of longitudinal bending of the layers caused the formation of linear uplift-folding in the northern part of the Graben, and echelons of scaly thrust covers in the southern. At the Mesozoic and Cenozoic epochs, in the mode of interference of the reverse–thrust and horizontal-strike-slip fields, the Hercynian thrust lattice and the near-fault uplift folds underwent collisional deformation with the formation of coulisse–jointed folded zones and echeloned thrust covers. Based on the kinematic model of tectonic inversion of the Western Donets Graben, the geodynamics of the formation of the transition zone between the Dnieper–Donets Basin and the Donetsk Foldbelt is reconstructed. These data are the basis for adjusting the regional schemes of tectonic and oil and gas geological zoning. Scientific novelty and practical significance. The grouping of the compression axes in the western part of the Donbass caused the formation of a gorst-like geoblock-stamp, under the pressure of which the dislocated geomasses were thrusting onto the syneclisic cover of the southeastern segment of the depression. In the Western Donetsk Graben, the allochthonous stratum formed the body of the tectonic wedging geomas segment. Along the main strike–slip faults, which form the "tectonic rails" of the invasion, geodynamic zones of displacement of geomas were formed, composed of en-echelon articulated upthrust-folds. In its foreland, at the ends of the main strike–slip faults, an advanced scaly compression fan was formed, and in the hinterland, folded sutures were formed on the roots of the thrust covers. The main result of the research is a fundamentally new kinematic model of tectonic inversion of the Dnieper-Donetsk Basin. The model provides that the deformations of the riftogenic structure within the Graben were carried out according to the kinematic mechanism of the formation of a transverse orocline protruding under the pressure of the tectonic geoblock-stamp of the Donetsk Foldbelt.

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DEEP STRUCTURE OF SOUTH-EASTERN PART OF THE WEST SIBIRIAN PLATE AND IN THE SALAIR ACCORDING TO MAGNETOTELLURIC SOUNDINGS

Interexpo GEO-Siberia ◽

10.33764/2618-981x-2019-2-2-80-86 ◽

2019 ◽

Vol 2 (2) ◽

pp. 80-86

Author(s):

Elena Pospeeva ◽

Vladimir Potapov

Keyword(s):

Electrical Conductivity ◽

Deep Structure ◽

The South ◽

The West ◽

Geological Structures ◽

Magnetotelluric Soundings ◽

South Eastern ◽

First Results

The first results of magnetotelluric studies carried out on the profile of v. Talmenka – Leninsk-Kuznetsky (South-Eastern part of the West Siberian plate and Salair) are considered, the main features of the distribution of deep electrical conductivity in the two main geological structures of the study area: the South-Eastern part of the West Siberian plate and the Salair zone are shown.

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