RELIEF. TEXT

Plains prevail in the relief of Ukraine’s territory (95% of the total area), they are the part of the East European Plain, one of the largest in Europe. On the south west and south the plains are edged with the mountains.

The relief of Ukraine’s territory has been formed under the conditions of complex interaction of endogenous, exogenous and anthropogenic factors, which resulted in regional morphostructural and morphosculptural regularities and peculiarities. Morphostructures are historical-genetic categories that reflect the influence of a group of endogenous factors on the relief formation, in particular the influence of tectonic structure on the spatial distribution of orographic elements, tectonic movements of the earth’s crust on dynamics, correlation of destructive and constructive exogenous processes and their intensity. Exogenous processes have the dominant role in morphosculptures formation, genetically and spatially they are submitted to morphoclimatic zoning and controlled by morphostructural conditions.

Orography. The average absolute height of the plains is 175 m; the surface inclines from the north to the south, as well as from the west to the east – to the Dnipro valley. The maximum absolute height of the relief is 515 m (Mt. Berda), minimal absolute heights (0–15 m) are found on the coasts of the Black Sea and the Sea of Azov.The plains orographic plan is determined by a complex combination of uplands and lowlands whose axis are oriented from the northwest to the southeast and sublatitudinally. The Podillia Upland (the length is about 600 km, the width is almost 200 km) with absolute heights of 300–400 m (the maximum absolute height is 471 m, Mt. Kamula) has the highest hypsometric position. The Donets’ Upland (the length is 350 km, the width is 150 km) is characterized by average heights of 200–250 m (the maximum absolute height is 367 m, Mt. Mohyla-Mechetna). The Volyn’ Upland (the length is about 250 km, the width is 50–100 km) has heights of 220–280 m, the maximum absolute height is 342 m. The Dnipro Upland (the length is almost 500 km, the width is 175–200 km) has the average absolute heights of 150–170 m in the south and 220–240 m in the north, the maximum absolute height is 322 m. The Azov Sea Coastal Upland (the length is almost 140 km, the width is 33 km) has absolute heights of 200–250 m, the maximum absolute height is 324 m (Mt. Bel’mak-Mohyla). The Black  Sea Coastal Lowland (the length is almost 600 km, the width is 120–150 km) has the lowest hypsometric position characterized by absolute heights of 150–170 m in the north and 0–15 m in the south; the maximum absolute height is 179 m (the Tarkhankut Upland). The Dnipro Lowland (within Ukraine’s borders the length is 600 km, the width is 200–250 km) has the average absolute heights of 50–170 m, the dominant heights – 170–200 m. The Polissia Lowland (within Ukraine’s borders the length is almost 450 km, the width is up to 100 km) is characterized by the average absolute heights of 150–200 m; the maximum absolute height is 316 m.

The plains are edged with the Ukrainian Carpathians and the Crimean Mountains. The Ukrainian Carpathians (the length is 280 km, the width is above 100 km) have absolute heights of 300–400 m near the foots of the northeastern and southwestern macroslopes, 1 500–2 000 m – on the main mountain ridges; the maximum absolute height is 2 061 m (Mt. Hoverla). Within the Ukrainian Carpathians several orographic units are distinguished: the Eastern Beskydy, the Gorgany, the Pokuttia-Bukovyna Carpathians, the Vododil’nyi (Watershed) Range, the Polonyns’kyi Range, the Rakhiv Mountains, the Chornohora, the Volcanic Range, the Forecarpathian Upland, the Transcarpathian Lowland. The Crimean Mountains (the length is 150 km, the width is 50 km) have absolute heights from 250 m to 1 200 m, maximum absolute height is 1 545 (Mt. Roman-Kosh). They compose the Main (absolute heights are 1 000–1 200 m), Inner (the absolute heights are 500 m) and Outer (absolute heights are 250 m) mountain ridges, divided by depressions.

Morphostructure. Morphostructures of Ukraine’s territory took their contemporary forms throughout the Neotectonic stage of development under conditions differentiated in space and time, variable according to amplitudes, velocities and directions (unidirectional, oscillating) of the earth’s crust tectonic movements, volcanism manifestations as well as ambiguous proportions of denudation and accumulation. According to the relation of relief and tectonic structures the highest rank regional morphostructires of platform plains orogens are distinguished on the territory of Ukraine as well as morphostructures of transition zones that include both plain-platform and orogenic elements.

The further division of regional morphostructures is specified by the degree of platform or orogenic geostructures revealing in characteristics of orography, morphology and morphodynamics of the relief.

Plain-platform morphostructures. The main orographic plain units correspond as a rule to the large platform geostructures: the and the Coastal Uplands to the Ukrainian Shield, the Donets’ Upland to the Donetska folded structure, the Podil’ and the Volyn’ Uplands to the structures of the western slope of the Ukrainian Shield, the dnipro and the Black Sea Coastal Lowlands to the tectonic depressions of the same name, the Polissia Lowland to the northern part of the Ukrainian Shield and its western slope.

Plain-platform morphostructures have been formed under conditions of Neotectonic (Late Oligocene-Anthropogene) uplifts, subsidences and sign-variable earth’s crust movements, which defined in time and space relation of destructive and constructive relief-forming processes. The most part of morphostructures are inherited concerning the main geostructures (the Dnipro-Donets’, the Black Sea Coastal, the Prypyat’ depressions, the Donets’ folded structures). The plains and hump-hills of the Volynska and the Podilska Uplands belong to the inverted morphostructures, this corresponds to the subsidence of crystalline basement on the western and southwestern slopes of the Ukrainian Shield. Morphostructures of the Ukrainian Shield belong to the inherit-regenerated ones.

Within the plain-platform territory socle plains and hump-hills are wide-spread, they have been formed on the Shield, and the protrusions of the folded basement of the ancient platform, as well as plate plains which have been formed on the heterochronous deposits. According to the relation of denudation and accumulative processes during their formation they are divided into stratal-denudation (structural-denudation, denudation) and stratal-accumulative ones.

Socle structural-denudation plains and hump-hills which had been formed mostly on the crystalline rocks are spread within the  Dnipro (the Ovrutch horst etc.) and the Azov Sea Coastal Uplands. Socle denudation plains, which had been formed on slightly uplifted crystalline basement, overlapped by a relatively small sedimentation thickness, are spread both on the western and southwestern slopes of the Dnipro Upland and on the Donets’ Upland, as well as in the central and eastern parts of Polissia Lowland within the boundaries of the Ukrainian Shield.

Structural-denudation plains and hump-hills which had been formed on the plate sedimentations are mostly represented on the Podilska Upland, the Roztochchia, the Volyn’ Upland, the Holohoro-Kremenets’ki Mountains, the Mizots’kyi Ridge and the Tarkhankut Upland. Denudation stratal-stepped plains prevail in the relief of the southwestern spurs of the Middle Russian Upland and adjacent parts of the Poltava Plain, the Black Sea Coastal Lowland, including the plain part to the Crimean Peninsula and coastal plains bordering upon the Azov Sea Coastal Upland in the south.In the contemporary relief stratal-accumulative and accumulative plains of different origin take up a smaller territory as compared with stratal-denudation ones. They are connected with territories experienced relative or absolute subsidence during the Late Pliocene and Anthropogene and characterized by accumulation of heterogenetic continental sediments within continental glaciations spread, in large river valleys and deltas. They can be found in some sections of the Polisska, the Dniprov and the Black Sea Coastal Lowlands. Active faults and brachyanticlines are represented in the relief of plain-platform morphostructures.

Orogenic morphostructures. The Ukrainian Carpathians and the Crimean Mountains belong to the collisional orogens type formed in zone of lithospheric plates collision. Morphostructures of different types have been formed here because of the manifestation of neotectonic dome-lumped elevations of different intensity as well as horizontal movements of the earth’s crust.

Genetically orogenic morphostructures are represented by denudation-tectonic, structural-denudation, denudation and volcanic middle- and low-mountains characterized by different degree of denudation of the initial tectonic relief on the background of manifestation of relief-forming crust movements of different intensity. The Ukrainian Carpathians’ morphostructures have been formed under conditions of active dome-block elevations and intensive horizontal neotectonic crust movements. Longitudinal Carpathians tectonic structures are brightly represented in the relief. Denudation-tectonic and structural-denudation dome-lumped, fold-thrusted, fold-lumped, lump-blocked middle- and low-mountains, which reflect the relation of vertical and horizontal relief-forming crust movements, correspond to the Flish Carpathians. In the southwest of mountain structure there are denudation-volcanic middle- and low-mountains, represented by the system of destructed volcanic structures of Neogene period. From the southwest they are adjoined to the Zakarpattia (Transcarpathian) Lowland that corresponds to the foredeep of the same name, within which stratal-accumulative plain has been formed. Local structures, horst-anticline and monocline ridges, mountain massifs, grabens and faults are represented in the Ukrainian Carpathians’ relief.

Morphostructures of the Crimean Mountains are represented by denudation-tectonic, structural-denudation, denudation monocline-lumped, fold-lumped low- and middle-mountains, formed on Mesozoic-Cenozoic deposits under conditions of differentiated neotectonic uplifts, whose total amplitudes decrease from the Main Range northwards to the Inner and Outer Ranges. Normal fault-slides, normal faults, intrusive massifs, and folds are represented in the Crimean Mountains relief.

Morphostructures of transitional zones of the Ukrainian Carpathians, the Crimean Mountains and platform struc-tures are corresponded to plains and low-mountains with stratal-denudation (structural-denudation, denudation) and stratal-accumulative relief which had been formed mainly under the conditions of piedmont marginal platform foredeeps under sign-variable neotectonic crust movements. Morphostructures of transitional zones belong to the category of inverted (the Peredcarpattia (Forecarpathians) Upland) and inherited (the Indol Lowland) ones. Transitional zone of the Ukrainian Carpathians and adjacent plains is represented by more diverse relief (structural-denudation, denudation, stratal-accumulative) as compared with transitional zones of the Crimean Mountains and adjacent plains. The northern parts of both transitional zones are characterized by the overlap of morphostructure adjacent piedmont foredeeps by orogens morphostructures. Representation of structural characteristics of platform and orogen types in the relief is a peculiarity of morphostructural plan of transitional zone.

Morphosculpture. Morphosculptural features of Ukraine’s territory are determined by the combination of zonal (relict and recent) and azonal relief forms, which are genetically connected with various exogenous relief-forming processes in different morphoclimatic zones.

Relict morphosculpture is connected with the activity of the Oka and the Dnipro continental glaciers that came into Ukraine’s territory in Anthropogene. They left different exarative erosive, accumulative glacial and fluvial-glacial relief forms, their morphology and structure are closely related to the morphostructural framework of the Polisska, the Dnipro Lowlands as well as northeastern slope of the Dnipro Upland.

Inherited morphosculpture has been developed within Late Cainozoe-Anthropogene. It is represented with heterochronous forms of fluvial, gravitational, karst, aeolian, marine and lacustrine origin.

Fluvial morphosculpture with a complex of erosive and accumulative forms, of different ranks and types of river valleys in particular and a series of Pliocene-Anthropogene terraces above the flood-plains, among which are leaning, embedded and superimposed ones, is wide-spread. The main river valleys of Ukraine have been formed in Pre-Anthropogene, this is confirmed with heterochronous alluvial deposits, which have been carefully studied in the left-bank side of the Dnipro basin, the Siverskyi Donets’, Desna rivers valleys, etc. Erosive gorge-ravine morphosculpture is highly developed within the Dnipro, the Podilia Uplands, the Poltava Plain and some other regions.

Accumulative fluvial-deltaic morphosculpture is represented by Anthropogenic morphologically different plains in the lower reaches of the Dnipro and Danube rivers and by Pliocene the old Balta Plain, fragments of which are situated in the interfluve of Dnister and Southern Buh rivers. Alluvial-lacustrine and alluvial-proluvial relief types of Anthropogene Age are restricted by piedmont the Ukrainian Carpathians and the Crimean Mountains. Marine terraces and estuary-marine relief forms of Anthropogene Age occur fragmentarily on the coasts of the Black Sea and the Sea of Azov.

On the whole, the denudation morphosculpture, morphologic features of which have been formed as the result of linear erosion action, karst, gravitational and other destructive relief-forming processes, prevails in the contemporary relief of Ukraine. Slides and avalanches, occurring on the plain and in the mountains, take the leading place among gravitational forms. They have been formed through different mechanism. These forms are developing in heterochronous rocks and have different morphology. The plains and hump-hills of the Podilia, the Peredcarpattia (Forecarpathians), the Donets’ Uplands, the Black Sea Coastal and the Zakarpattia (Transcarpathian) Lowlands are complicated with karst and suffosive-subsided forms of morphosculptures. The forms of open, half-covered karst in gypsum-anhydrous rocks are spread on the Podilia Upland. The forms of open and covered karst in the limestones are spread on the spurs of the Middle Russian Upland and the Polisska Lowland. The forms of open and covered karst in the salt deposits are spread on the northern slope of the Donets’ Upland, on the Zakarpattia (Transcarpathian) Upland and the Zakarpattia (Transcarpathian) Lowland. Morphosculptures of the mountainous part of Ukraine’s territory are mainly represented with fluvial-erosive, glacial, gravitational and karst forms. Morphosculptures age varies from Oligocene to present-day.

Polygenic leveling surfaces correlated with each other, have been formed as a result of the long-term denudative and accumulative processes in mountains and on plains during certain stages. Thus, the level of the Urdu (absolute height is 1 300–1 450 m) of the Ukrainian Carpathians is compared with the Polissia level (200–250) in the plain-platform part, the Under-Polonyna level (900–1 000 m) – with the dnipro level (250–300 m), the Kichersky level (500–700 m) – with the Podillia one (350–400 m), the Upper plateau of the Crimean Mountains (1 000–1 200 m) – with pediments of the Donets’ Upland (250–300 m), and the Lower plateau (500–700 m) – with accumulative-denudation plains of its outskirts. The age of leveling surface varies from Mesozoy to Pliocene.

Recent natural exogenous relief-forming processes are represented by surface washout and subslope accumulation, linear erosion and fluvial accumulation in river beds, on floodplains, in deltas, proluvial cones, by gravitational processes (slides, taluses, avalanches), creeps, solifluction, mudflows, suffosion, subsidence, karst, abrasion, aeolian deflation and accumulation, waterlogging, and endogenous ones – by slow and rapid (seismic) recent tectonic crust movements that control the expansion and intensity of exogenous processes. Anthropogenic processes whith arise from mining, engineering-constructive, hydrotechnic, agrotechnic, meliorative and other economic activities and determine different anthropogenic changeability of natural relief are the powerful factors of contemporaneous geomorphogenesis. Strongly-, averagely-, weakly anthropogenic transformed relief can be distinguished. Anthropogenic morphosculpture is wide-spread, though it is especially developed within the Donets’ and the Peredcarpattia (Forecarpathians) Uplands, the Middle dnipro.

Zoning. The geomorphologic zoning is made on the multistage principle, regions of different taxonomic ranks cor­relate as a parts with the whole and reflect the peculiarities of the relief determined by the presence of morphostructural, morphosculptural, morphologic, morphometric and age differences. 3 geomorphological countries, 2 provinces (in moun­tains), 13 regions (8 – on plain, 5 – in the mountains), 36 subregions (21 – on plains, 15 – in the mountains), 158 districts (100 – on plain, 58 – in the mountains) are distinguished in Ukraine’s territory.