The West Siberian Plain belongs to the accumulative type and is one of the largest low-lying plains on the planet. Geographically, it belongs to the West Siberian plate. On its territory there are regions of the Russian Federation and the northern part of Kazakhstan. The tectonic structure of the West Siberian Plain is ambiguous and diverse.
Tectonic structures of Russia
Russia is located on the territory of Eurasia, the largest continent on the planet, which includes two parts of the world - Europe and Asia. The cardinal points are separated by the tectonic structure of the Ural Mountains. The map makes it possible to visually see the geological structure of the country. Tectonic zoning divides the territory of Russia into such geological elements as platforms and folded areas. The geological structure is directly related to the topography of the surface. Tectonic structures and landforms depend on which area they belong to.
Within Russia there are several geological regions. Tectonic structures of Russiarepresented by platforms, fold belts and mountain systems. On the territory of the country, almost all areas have undergone folding processes.
The main platforms within the territory of the country are East European, Siberian, West Siberian, Pechora and Scythian. They, in turn, are divided into plateaus, lowlands and plains.
The Ural-Mongolian, Mediterranean and Pacific are involved in the structure of the folded belts. Mountain systems in Russia - the Greater Caucasus, Altai, Western and Eastern Sayans, Verkhoyansk Range, Ural Mountains, Chersky Range, Sikhote-Alin. Can tell how they were formed, stratigraphic table.
The tectonic structure, landform on the territory of Russia is very complex and diverse in terms of morphology, geomorphology, origin and orography.
Geological structure of Russia
The position of the lithospheric plates that is observed today is the result of a complex long-term geological development. Within the lithosphere, large areas of land are distinguished, which differ from each other in the different composition of rocks, their occurrence and geological processes. During geotectonic zoning, attention is paid to the degree of change in rocks, the composition of the rocks of the foundation and sedimentary cover, and the intensity of movements of the foundation. The territory of Russia is divided into folded areas and areas of epiplatform activation. Geotectonic zoning covers everythingtectonic structures. The stratigraphy table contains data on the modern geotectonics of the territory of Russia.
Relief forms are formed due to deep movements and external influences. The activity of rivers plays a special role. In the process of their vital activity, river valleys and ravines are formed. The shape of the relief is also formed by glaciation. As a result of the activity of the glacier, hills and ridges appear on the plains. The shape of the relief is also influenced by permafrost. The result of freezing and thawing of groundwater is the process of soil subsidence.
The Siberian Precambrian platform is an ancient structure. In its central part, there is an area of Karelian folding; in the west and southwest, the Baikal folding has formed. In the region of the West Siberian and Siberian lowlands, the Hercynian folding has become widespread.
Relief of Western Siberia
The territory of Western Siberia gradually plunges from south to north. The relief of the territory is represented by a wide variety of its forms and is complex in origin. One of the important relief criteria is the difference in absolute elevations. On the West Siberian Plain, the difference in absolute marks is tens of meters.
The flat terrain and slight elevation changes are due to the small amplitude of plate movement. On the periphery of the plain, the maximum amplitude of uplifts reaches 100-150 meters. In the central and northern parts, the amplitude of subsidence is 100-150 meters. The tectonic structure of the Central Siberian Plateau and the West Siberian Plain in the late Cenozoic were inrelative calm.
Geographic structure of the West Siberian Plain
Geographically, in the north, the plain borders on the Kara Sea, in the south, the border runs along the north of Kazakhstan and captures a small part of it, in the west it is controlled by the Ural Mountains, in the east - by the Central Siberian Plateau. From north to south, the length of the plain is about 2500 km, the length from west to east varies from 800 to 1900 km. The area of the plain is about 3 million km2.
The relief of the plain is monotonous, almost even, occasionally the height of the relief reaches 100 meters above sea level. In its western, southern and northern parts, the height can reach up to 300 meters. The lowering of the territory occurs from south to north. In general, the tectonic structure of the West Siberian Plain is reflected in the terrain.
The main rivers - the Yenisei, the Ob, the Irtysh - flow through the plain, there are lakes and swamps. The climate is continental.
Geological structure of the West Siberian Plain
The location of the West Siberian Plain is confined to the epihercynian plate of the same name. The basement rocks are highly dislocated and belong to the Paleozoic period. They are covered with a layer of marine and continental Mesozoic-Cenozoic deposits (sandstones, clays, etc.) more than 1000 meters thick. In the depressions of the foundation, this thickness reaches up to 3000-4000 meters. In the southern part of the plain, the youngest are observed - alluvial-lacustrine deposits, in the northern part there are moremature - glacial-marine deposits.
The tectonic structure of the West Siberian Plain includes a foundation and a cover.
The foundation of the slab has the appearance of a depression with steep sides from the east and northeast and gentle slopes from the south and west. The basement blocks belong to the pre-Paleozoic, Baikal, Caledonian and Hercynian times. The foundation is dissected by deep faults of different ages. The largest faults of submeridional strike are East Zauralsky and Omsk-Pursky. The map of tectonic structures shows that the basement surface of the slab has an Outer marginal belt and an Inner region. The entire surface of the foundation is complicated by a system of ups and downs.
The cover is interbedded with coastal-continental and marine sediments with a thickness of 3000-4000 meters in the south and 7000-8000 meters in the north.
Central Siberian Plateau
The Central Siberian Plateau is located in the north of Eurasia. It is located between the West Siberian Plain in the west, the Central Yakut Plain in the east, the North Siberian Plain in the north, the Baikal region, Transbaikalia and the Eastern Sayan Mountains in the south.
The tectonic structure of the Central Siberian plateau is confined to the Siberian platform. The composition of its sedimentary rocks corresponds to the Paleozoic and Mesozoic periods. Its characteristic rocks are bedded intrusions, which consist of traps and bas alt covers.
The relief of the plateau consists of wide plateaus and ridges, at the same time there are valleys with steep slopes. The average height of the drop in the relief is 500-700 meters, butthere are parts of the plateau, where the absolute mark rises above 1000 meters, such areas include the Yenisei Ridge and the Angara-Lena Plateau. One of the highest parts of the territory is the Putorana Plateau, its height is 1701 meters above sea level.
Middle Ridge
The main watershed range of Kamchatka is the Sredinny Ridge. The tectonic structure is a mountain range, consisting of systems of peaks and passes. The ridge stretches from north to south and its length is 1200 km. A large number of passes are concentrated in its northern part, the central part represents large distances between the peaks, in the south there is a strong dissection of the massif, and the asymmetry of the slopes characterize the Sredinny Range. The tectonic structure is reflected in the relief. It includes volcanoes, lava plateaus, mountain ranges, peaks covered with glaciers.
The ridge is complicated by lower-order structures, the most striking of which are the Malkinsky, Kozyrevsky, Bystrinsky ridges.
The highest point belongs to the Ichinskaya Sopka and is 3621 meters. Some volcanoes, such as Khuvkhoytun, Alnay, Shishel, Ostraya Sopka, exceed the mark of 2500 meters.
Ural Mountains
The Ural Mountains is a mountain system located between the East European and West Siberian plains. Its length is more than 2000 km, the width varies from 40 to 150km.
The tectonic structure of the Ural Mountains belongs to the ancient folded system. In the Paleozoic, there was a geosyncline and the sea splashed. Starting from the Paleozoic, the formation of the mountain system of the Urals takes place. The main formation of folds occurred in the Hercynian period.
Intense folding took place on the eastern slope of the Urals, which was accompanied by deep faults and the release of intrusions, the dimensions of which reached about 120 km in length and 60 km in width. The folds here are compressed, overturned, complicated by overthrusts.
On the western slope, folding was less intense. The folds here are simple, without overthrusts. No intrusions.
Pressure from the east was created by a tectonic structure - the Russian platform, the foundation of which prevented the formation of folding. Folded mountains gradually appeared on the site of the Ural geosyncline.
Tectonically, the entire Urals is a complex complex of anticlinoria and synclinoria separated by deep faults.
The relief of the Urals is asymmetrical from east to west. The eastern slope drops steeply towards the West Siberian Plain. The gentle western slope smoothly passes into the East European Plain. The asymmetry was caused by the activity of the tectonic structure of the West Siberian Plain.
B altic Shield
The B altic Shield belongs to the northwest of the East European Platform, is the largest ledge of its foundation and is elevated above sea level. In North-westthe border runs with the folded structures of Caledonia-Scandinavia. In the south and southeast, the rocks of the shield submerge under the cover of sedimentary rocks of the East European Plate.
Geographically, the shield is tied to the southeastern part of the Scandinavian Peninsula, to the Kola Peninsula and Karelia.
The structure of the shield involves three segments, different in age - South Scandinavian (western), Central and Kola-Karelian (eastern). The South Scandinavian sector is tied to the south of Sweden and Norway. The Murmansk block stands out in its composition.
The central sector is located on the territory of Finland and Sweden. It includes the Central Kola block and is located in the central part of the Kola Peninsula.
Kola-Karelian sector is located on the territory of Russia. It belongs to the most ancient formation structures. In the structure of the Kola-Karelian sector, several tectonic elements are distinguished: Murmansk, Central Kola, Belomorian, Karelian, they are separated from each other by deep faults.
Kola Peninsula
The Kola Peninsula is tectonically tied to the northeastern part of the B altic crystalline shield, composed of rocks of ancient origin - granites and gneisses.
The relief of the peninsula has adopted the features of the crystalline shield and reflects traces of faults and cracks. The appearance of the peninsula was influenced by glaciers, which smoothed the tops of the mountains.
The peninsula is divided into western and eastern parts according to the nature of the relief. The relief of the eastern part is not as complex as the western one. The mountains of the Kola Peninsula are shapedpillars - on the tops of the mountains there are flat plateaus with steep slopes, lowlands are located below. The plateau is cut by deep valleys and gorges. The Lovozero tundra and Khibiny are located in the western part, the tectonic structure of the latter belongs to mountain ranges.
Khibiny
Geographically, the Khibiny belong to the central part of the Kola Peninsula, they are a large mountain range. The geological age of the massif exceeds 350 Ma. Mountain Khibiny is a tectonic structure, which is an intrusive body (solidified magma) of complex structure and composition. From a geological point of view, an intrusion is not an erupted volcano. The massif continues to rise even now, the change is 1-2 cm per year. More than 500 types of minerals are found in the intrusive massif.
Not a single glacier has been found in the Khibiny, but there are traces of ancient ice. The peaks of the massif are plateau-like, the slopes are steep with a large number of snowfields, avalanches are active, and there are many mountain lakes. The Khibiny are relatively low mountains. The highest elevation above sea level belongs to Mount Yudychvumchorr and corresponds to 1200.6 m.
