Geography abstract

Russian or East European Plain: description, dimensions and historical details.

2) Hydrography

4) Flora and fauna

III. The history of relief formation and climate fluctuations in Eastern Europe.

IV. Used Books.

Dimensions.

A significant part of the European part of Russia is located on one of the largest plains in the world - the East European (Russian), the length of which from west to east, from the country's borders to the Urals, reaches 1600 km, and from north to south, from the seas of the Arctic Ocean to the Caucasus mountains and the Caspian Sea - 2,400 km; the amplitude of the latest tectonic movements is low here; the main features of the relief were formed in the Late Cenozoic. Most of the territory of the East European Plain lies below 200 m above sea level; the highest point - 343 m - is located on the Valdai Upland. Nevertheless, the nature of the relief of the Russian Plain is rather complex. To the north of the latitude of Moscow, glacial landforms prevail - including moraine ridges, of which the most famous are the Valdai and Smolensk-Moscow Uplands (the latter reaches a height of 314 m); moraine, outwash, lacustrine-glacial lowlands are widespread. To the south of the latitude of Moscow, the uplands, directed mainly in the meridional direction, alternate with flat areas. On the heights, there are numerous ravines and gullies. In the west is the Central Russian Upland (maximum height 293 m), separating the upper reaches of the Dnieper, Oka and Don; here the valleys of small rivers are clearly defined; at the same time, large rivers have wide shallow floodplains; in some places a strong influence of aeolian processes and the formation of dunes are noted. To the east is the Privolzhskaya Upland, reaching a height of 329 m and steeply dropping to the river. The lower reaches of the Volga are within the Caspian Lowland, some parts of which are 90 m below sea level. To the south, the East European Plain extends up to the spurs of the Greater Caucasus. The vast Kuban and Kumskaya lowlands are separated by the Stavropol Upland, where heights from 300 to 600 m prevail (in the upper reaches of the Kuma there is also a group of island mountains up to 1401 m high). Human economic activity has greatly changed the relief of the East European Plain

Description.

1) Relief .

Almost the entire length is dominated by a gentle flat relief.

The East European Plain almost completely coincides with the East European Platform. This circumstance explains its flat relief, as well as the absence or insignificance of manifestations of such natural phenomena as earthquakes, volcanism. Large hills and lowlands have arisen as a result of tectonic movements, including along faults. The height of some hills and plateaus reaches 600-1000 meters.

On the territory of the Russian Plain, platform deposits lie almost horizontally, but their thickness in some places exceeds 20 km. Where the folded foundation protrudes to the surface, hills and ridges are formed (for example, Donetsk and Timan ridges). On average, the height of the Russian Plain is about 170 meters above sea level. The lowest areas are on the Caspian coast (its level is about 26 meters below the level of the World Ocean).

2) Hydrography.

Hydrographically, the territory of the East European Plain is divided into two parts. Most of them have drainage to the ocean. Northern rivers (Mezen, Onega, Severnaya, Dvina, Pechora) belong to the basin of the Arctic, western and southern - to the basin of the Atlantic oceans. The latter include rivers flowing into the Baltic (Neva, Western Dvina, Neman, Vistula, rivers of Sweden and Finland), Black (Dnieper, Southern Bug, Dniester) and Azov (Don) seas. The rivers of the Volga, Ural and some other basins flow into the Caspian Sea, which has lost its connection with the World Ocean.

3) Climate.

Moderate continental climate. It is characterized by moderately cold winters and warm summers with an average July temperature of +12 degrees C (off the coast of the Barents Sea) to +24 degrees C in the southeast (on the Caspian lowland). Average January temperatures vary from -8 degrees C in the west of the territory (along the border with the territory of Belarus) to -16 degrees C in the Urals. Precipitation occurs throughout the year from 800 mm in the west to 400 mm in the southeast. In the area of ​​moderate continental climate, moisture varies from excessive in the north, northwest to insufficient in the east and southeast. This is reflected in the change of natural zones from taiga to steppe.

The history of relief formation and climate fluctuations in Eastern Europe.

The relief of Eastern Europe, modern plains, lowlands and mountains have been formed as a result of complex and long geological development. The most ancient structure of crystalline rocks, representing the geological basis of Eastern Europe, is the Russian Platform, in the rigid foundation of which mining and educational processes ceased relatively early.

This, as well as the activity of the glaciers, explains the predominance of the flat landscape. Where the platform was in contact with others, there were moving regions of the earth's crust. Its vertical ups and downs, in combination with magmatic processes, led to the formation of folds, active manifestations of volcanism. The end result of this process was the formation of the mountainous regions of Eastern Europe - the Urals, the Caucasus, the Carpathians.

The last stage of geological history, the Quaternary period, was of great importance in the formation of the most important features of the physical geography of Eastern Europe. It is also called anthropogen (Greek antropos - "man" and genos - "birth"), that is, the time of the emergence and development of man, and the beginning is dated from 1 million to 600 thousand years ago. In the geological and natural area, this is the period of continental glaciations. It was during the Ice Age that soil varieties appeared, the movement of glaciers led to the creation of modern relief and the formation of coastlines.

Moraine ridges, boulder clays, sands and other glacial deposits cover the main part of the northern half of the plain. The last significant changes in the natural environment of Eastern Europe date back to the 12th – 10th millennia BC. NS. This is the time of the so-called Valdai glaciation, the southern border of which ran approximately along the line Vilnius - Vitebsk - Valdai - Vologda. It was after him that natural and climatic conditions, the main character of which has survived to our time. The postglacial period, which began 8-10 thousand years ago, is a time of global warming.

It is characterized by the retreat from Europe to the north and the melting of the Scandinavian ice sheet, the rise of the earth's crust freed from the ice load (this process was uneven in time and space), and a slow rise in the level of the World Ocean. The evolution of one of the huge lakes that existed at the edge of the glacier over several millennia led to the emergence of the Baltic Sea, which acquired its present form about 4.5 thousand years ago. By this time, the warm interval (the so-called "climatic optimum") ended, the average annual air temperature dropped, and the humidity, on the contrary, increased and the modern type of climate was formed.

In the historical period (for Eastern Europe, more or less detailed information from written sources has been available since the 5th century BC), the most important natural conditions - topography and climate - did not undergo global changes. This is especially true of the relief. Some local changes in it are associated with ongoing mining and educational processes. The coastal areas of the Crimean Peninsula and the Black Sea coast of the Caucasus were subject to certain fluctuations, as a result of which part of the ancient cities located in this region ended up on the seabed. Quite significant changes have occurred and are occurring with the northern shores of the Caspian Sea, which are known as transgression and regression of the Caspian, but they are more associated with climate change. In general, secondary elements of the physical and geographical landscape changed - the outlines and position of coastlines, river flows, sand boundaries, etc.

The climate is subject to some periodic fluctuations, which, however, do not lead to major shifts in physical geography and vegetation distribution. So, at the beginning of the Iron Age (the turn of the II-I millennia BC) and later, the climate was in general terms almost the same as now, but cooler and more humid. Forests along the river valleys in the south of the Russian Plain descended to the shores of the Black and Azov Seas. The floodplains of the lower Dnieper were covered with a thick forest on both banks of the river. To date, these forests have been destroyed by humans, and not disappeared due to any catastrophic climate change.

In the early Middle Ages (late 1st - early 2nd millennium AD), there was a "small climatic optimum" - a period of significant warming in Western Europe and the North Atlantic. It is no coincidence that this time is considered the "Viking Age": warming made possible in the 9th-11th centuries. long voyages in the North Atlantic and the discovery of Iceland, Greenland and North America... However, already from the XIV century. cooling begins in Western Europe and the 15th – 19th centuries. often defined as the "Little Ice Age" - this is the time of the onset of mountain glaciers, cooling of waters, and severe winters. A new period of warming began at the end of the 19th century, and in the 20th century. it has acquired a large-scale character.

The East European Plain is the steppes, which are the rich grain granaries of the country, where the highest quality wheat is grown, the forests of the North, the endless expanses of which are an ideal natural pasture and unique habitat for hundreds of thousands of beasts. This is a variety of nature, tree species, vegetation cover, temperature regime and humidity. Where is the main plain of Russia and what are its features - more on that later.

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Special features

East European Plain on the map

Within a huge flat area, seasonal temperatures and humidity levels fluctuate within significant limits. Moreover, in one region snowfalls can occur, creating impenetrable drifts, while in the other endless forests make noise with foliage and fragrant meadows bloom. It is known that these expanses are part of the East European Platform. It is ancient and geologically stable. with a giant shield on the surface, which is closely bordered by the belts of tectonic folding. The outlines of this flat territory, the most significant on this side of the planet, impress anyone who is familiar with the basics of geography.

What the East European Plain looks like on the map:

• frame its eastern border of the ridge;
• the southern outskirts are closely adjacent to the Mediterranean fold belt and the Scythian plate, which occupies the area of ​​the foothills of the Caucasus and Crimea;
• the length of the East European Plain in the western direction runs along the Danube, close to the coasts of the Black Sea and Azov.

Note! Due to the venerable geological age, in these practically endless expanses, only insignificant hills can be found, and even then only in the northern regions.

As a result of the movement of the glacier to the south, the elements of tectonic plates can be seen simply with our own eyes, in the region of Karelia and in some areas of the Baltic. Further movement of endless ice masses, combined with a low altitude relative to sea level, resulted in an almost ideal surface.

In terms of economic opportunities, the area of ​​this vast territory differs most densely populated in rural areas, here great amount cities and towns, urban-type settlements. Natural resources are impressive with their diversity. For many thousands of years, the vastness of the territory has been successfully developed by man as an industrial and agricultural base.

About tectonics

Quite a complex geological structure and structural features for many decades, various scientists have studied from amateur amateurs to professional scientists with a worldwide reputation, who gave their description the territory of the East European Plain.

In some scientific schools, it is better known as the Russian Plain, on which geologists distinguish two of the most significant protrusions - the Ukrainian Shield and the Baltic Shield, areas with a small or deep occurrence of basement elements.

Such a relief is associated with huge areas and significant geological age of formations and structures. The foundation consists of several layers.

Archean layer complex. The tectonic structure is quite peculiar, characterized by the exposure of the basement. These are the regions of the Baltic, Karelia, the Kola Peninsula, known for their rocks, as well as the Konotop, Podolsk and Pridneprovsky massifs. They formed more than three million years ago, are rich in significant deposits of graphite, ferruginous quartzite and other highly valuable minerals. Another type of Archean is no less interesting, which is represented by the Voronezh anteclise, where the basement is insignificant. The age of the formations according to the data today is about 2.7 million years.

Features of descents and hills

As mentioned above, the East European Plain in ancient times was significantly affected by the glacier, which was facilitated by its geographical position... During the Ice Age, almost the entire area was completely covered a multi-meter layer of ice, which could not but have a physical impact not only directly on the surface layers of the soil, but also indirectly on deep-lying structures. As a result of such phenomena, ups and downs appeared on the surface at a fairly low altitude of the plain relative to sea level. By and large, this area is a platform cover, consisting of several deposits:

• proterozoic;
• paleozoic;
• Mesozoic;
• Cenozoic.

With a significant multi-thousandth pressure of glaciers that literally leveled the surface of these territories, the formation of the basement is distinguished by an intermittent trend. A feature of the structure is alternate arrangement of relief ups and downs... The profile looks quite interesting in the field of geology:

• subsidence of the Caspian lowland area;
• Sarmatian Upland;
• The Baltic-Central Russian lowering of the relief;
• zone of the Baltic shield.

According to the data obtained thanks to modern calculation methods, there is reliable information about the thickness of the platform pie in different regions of the plain. Average data within 35-40 kilometers. The maximum is the Voronezh anteclise - about 55 kilometers; the minimum is attributed by scientists to the Caspian region.

Note! Approximately the East European Plain has a fairly solid age - from 1.6 to 2.6 million years

The features of the relief of this vast territory are that the most ancient formations are recorded in the area of ​​its eastern borders. The oldest elements of the massif are the most static elements of the geological structure, this can be said about the Tatar, Caspian and Zhigulevsko-Pugachev massifs, separated by a protoplatform cover.

About the nuances of syneclises and anteclises

The Caspian syneclise is considered the most ancient; numerous deep salt domes are determined here, which most of all typical for the Guryev zone.

Here they occupy areas from tens to hundreds of square meters. kilometers. Despite the name, the most diverse shapes and outlines are inherent in the domes - a circle, an ellipse, there are also irregular shapes education.

The largest known domes in this region are Chelkarsky, Dossorsky, Indersky, Makatsky, Eltonsky, Sakharno-Lebyazhinsky.

Long-term studies of geologists and specialized methods of photography and scanning from orbit make it possible to obtain reliable data on the tectonic structure of the Russian Plain. The research results are as follows:

1. Moscow syneclise is the largest on the East European platform... Its northern outlines are determined by a pair of uplifts - Soligalichsky and Sukhonsky. The researchers define the lowest part of the region near the city of Syktyvkar, where the Seregovsky salt domes formed by Devonian salts were identified.
2. The Volga-Ural anteclise is practically an equal in importance tectonic element. Numerous changes in relief are recorded here, the most significant height is the Mordovian Tokmovsky arch. Anteclise carries

EASTERN EUROPEAN PLAIN (Russian Plain), one of the largest plains the globe... Occupies mainly Eastern and Western Europe, where the European part of Russia, Estonia, Latvia, Lithuania, Belarus, Moldova, most of Ukraine, western Poland and eastern Kazakhstan are located. The length from west to east is about 2400 km, from north to south - 2500 km. In the north it is washed by the White and Barents Seas; in the west it borders on the Central European Plain (approximately along the valley of the Vistula River); in the southwest - with the mountains of Central Europe (Sudetenland, etc.) and the Carpathians; in the south it goes to the Black, Azov and Caspian Seas and is bounded by the Crimean Mountains and the Caucasus; in the southeast and east - by the western foothills of the Urals and Mugodzhary. Some researchers include the southern part of the Scandinavian Peninsula, the Kola Peninsula and Karelia in the East European Plain, others attribute this territory to Fennoscandia, the nature of which differs sharply from the nature of the plain.

Relief and geological structure.

The East European Plain geo-structurally corresponds mainly to the Russian plate of the ancient East European platform, in the south - to the northern part of the young Scythian platform, in the northeast - to the southern part of the young Barents-Pechora platform.

The complex relief of the East European Plain is characterized by slight fluctuations in heights (average height about 170 m). The highest heights are on the Bugulma-Belebeyevskaya (up to 479 m) and on the Podolsk (up to 471 m, Mount Kamula) uplands, the lowest (about 27 m below sea level, 2001; the lowest point in Russia) are on the coast of the Caspian Sea. On the East European Plain, two geomorphological areas are distinguished: the northern moraine with glacial landforms and the southern non-moraine with erosional landforms. The northern moraine region is characterized by lowlands and plains (Baltic, Upper Volga, Meshchera, etc.), as well as small uplands (Vepsovskaya, Zhemaitskaya, Haanja, etc.). In the east - Timan ridge. The extreme north is occupied by vast coastal lowlands (Pechora and others). In the northwest, in the area of ​​distribution of the Valdai glaciation, accumulative glacial relief prevails: hilly and ridge-moraine, depression with flat lake-glacial and outwash plains. There are many swamps and lakes (Chudsko-Pskovskoe, Ilmen, Upper Volga lakes, Beloye, etc.) - the so-called poozerie. To the south and east, in the area of ​​the more ancient Moscow glaciation, smoothed undulating moraine plains, reworked by erosion, are characteristic; there are basins of drained lakes. Moraine-erosional hills and ridges (Belorusskaya Ridge, Smolensk-Moscow Upland, etc.) alternate with moraine, outwash, lacustrine-glacial and alluvial lowlands and plains (Mologo-Sheksninskaya, Verkhnevolzhskaya, etc.). Ravines and gullies are more common, as well as river valleys with asymmetric slopes. On the southern border of the Moscow glaciation, woodlands (Polessye lowland, etc.) and opolye (Vladimirskoye, etc.) are typical.

The southern non-moor region of the East European Plain is characterized by large uplands with erosional gully-ravine relief (Volyn, Podolsk, Pridneprovskaya, Priazovskaya, Central Russian, Privolzhskaya, Ergeni, Bugulma-Belebeevskaya, General Syrt, etc.) and low accumulation , related to the area of ​​the Dnieper glaciation (Dnieper, Oksko-Don, etc.). Wide asymmetric terraced river valleys are characteristic. In the southwest (the Black Sea and Dnieper lowlands, the Volyn and Podolsk uplands, etc.) there are flat watersheds with shallow steppe depressions, the so-called "saucers", formed due to the widespread development of loess and loess-like loams. In the northeast (Vysokoe Zavolzhye, General Syrt, etc.), where there are no loess-like sediments, and bedrocks come to the surface, watersheds are complicated by terraces, and the peaks are outcrops of weathering, the so-called shikhans. In the south and southeast there are flat coastal accumulative lowlands (Black Sea, Azov, Caspian).

Climate... In the extreme north of the East European Plain, there is a subarctic climate; in most of the plain, there is a temperate continental climate dominated by western air masses. With distance from the Atlantic Ocean to the east, the climate becomes more continental, harsh and dry, and in the southeast, on the Caspian lowland, it becomes continental, with hot dry summers and cold winters with little snow. average temperature January from -2 to -5 ° С, in the southwest it drops to -20 ° С in the northeast. The average July temperature rises from north to south from 6 to 23-24 ° С and up to 25 ° С in the southeast. The northern and central parts of the plain are characterized by excessive and sufficient moisture, the southern - insufficient and arid. The most humid part of the East European Plain (between 55-60 ° north latitude) receives 700-800 mm of precipitation per year in the west and 600-700 mm in the east. Their number decreases to the north (in the tundra 250-300 mm) and to the south, but especially to the southeast (in the semi-desert and desert 150-200 mm). The maximum precipitation occurs in the summer. In winter, the snow cover (10-20 cm thick) lies from 60 days a year in the south to 220 days (60-70 cm thick) in the northeast. In the forest-steppe and steppe, frosts, droughts and dry winds are frequent; in semi-desert and desert - dust storms.

Rivers and lakes. Most of the rivers of the East European Plain belong to the Atlantic basins [the Neva, Daugava (Western Dvina), Vistula, Neman, and others flow into the Baltic Sea; to the Black Sea - Dnieper, Dniester, Southern Bug; into the Sea of ​​Azov - Don, Kuban, etc.] and the Arctic Oceans (Pechora flows into the Barents Sea; Mezen, Northern Dvina, Onega, and others) into the White Sea. The Volga (the largest river in Europe), Ural, Emba, Bolshoi Uzen, Maly Uzen, etc. belong to the basin of internal flow, mainly of the Caspian Sea. All rivers are predominantly snow-fed with spring floods. In the southwest of the East European Plain, rivers do not freeze every year; in the northeast, freeze-up lasts up to 8 months. The long-term runoff module decreases from 10-12 l / s per km 2 in the north to 0.1 l / s per km 2 or less in the southeast. The hydrographic network has undergone strong anthropogenic changes: a system of canals (Volga-Baltic, White Sea-Baltic, etc.) connects all the seas washing the East European Plain. The flow of many rivers, especially those flowing to the south, is regulated. Significant stretches of the Volga, Kama, Dnieper, Dniester and others have been transformed into cascades of reservoirs (Rybinskoe, Kuibyshevskoe, Tsimlyanskoe, Kremenchugskoe, Kakhovskoe, etc.). There are numerous lakes: glacial-tectonic (Ladoga and Onega are the largest in Europe), moraine (Chudsko-Pskov, Ilmen, Beloe, etc.), etc. Salt lakes (Baskunchak, Elton, Aralsor, Inder) were formed by salt tectonics, since some of them arose during the destruction of the salt domes.

Natural landscapes. The East European Plain is a classic example of a territory with a clearly defined latitudinal and sublatitudinal zonation of landscapes. Almost the entire plain is located in the temperate geographic zone, and only the northern part is in the subarctic. In the north, where permafrost is widespread, tundras are developed: moss-lichen and shrub (dwarf birch, willow) on tundra gley, bog soils and podburs. To the south, a narrow strip stretches a forest-tundra zone with undersized birch and spruce woodlands. Forests cover about 50% of the plain. The zone of dark coniferous (mainly spruce, in the east - with the participation of fir) European taiga, in places swampy, on podzolic soils and podzols, expands to the east. To the south, there is a subzone of mixed coniferous-deciduous (oak, spruce, pine) forests on sod-podzolic soils. Pine forests are developed along the river valleys. In the west, from the coast of the Baltic Sea to the foothills of the Carpathians, there is a subzone of broad-leaved (oak, linden, ash, maple, hornbeam) forests on gray forest soils; forests wedge out to the Volga and have an insular distribution in the east. Primary forests are often replaced by secondary birch and aspen forests, which occupy 50-70% of the forest area. Opolian landscapes are peculiar - with plowed flat areas, remnants of oak forests and a ravine network along the slopes, as well as woodlands - swampy lowlands with pine forests. From the northern part of Moldova to the South Urals, there is a forest-steppe zone with oak forests (mostly cut down) on gray forest soils and rich-herb-cereal meadow steppes (preserved in reserves) on chernozems (the main fund of arable land). The share of arable land in the forest-steppe is up to 80%. The southern part of the East European Plain (except for the southeast) is occupied by forb-feather grass steppes on ordinary chernozems, which are replaced to the south by fescue-feather grass dry steppes on chestnut soils. Most of the Caspian lowland is dominated by wormwood-feathergrass semi-deserts on light chestnut and brown desert-steppe soils and wormwood-saltwort deserts on brown desert-steppe soils in combination with solonetzes and salt marshes.

Ecological situation and specially protected natural areas... The East European Plain has been developed and significantly changed by man. In many natural zones, natural-anthropogenic complexes dominate, especially in the landscapes of steppe, forest-steppe, mixed and broad-leaved forests. The territory of the East European Plain is highly urbanized. The most densely populated (up to 100 people / km 2) are zones of mixed and deciduous forests. Typical anthropogenic relief: waste heaps (height up to 50 m), quarries, etc. A particularly tense ecological situation in large cities and industrial centers (Moscow, St. Petersburg, Cherepovets, Lipetsk, Rostov-on-Don, etc.). Many rivers in the central and southern parts are heavily polluted.

For the study and protection of typical and rare natural landscapes, numerous reserves, national parks and wildlife sanctuaries have been created. In the European part of Russia (2005) there were over 80 reserves and national parks, including more than 20 biosphere reserves (Voronezh, Prioksko-Terrasny, Central Forest, etc.). Among the oldest reserves: Bialowieza Forest, Askania Nova and the Astrakhan reserve. Among the largest are the Vodlozersky National Park (486.9 thousand km 2) and the Nenets Nature Reserve (313.4 thousand km 2). Sites of the primary taiga "Virgin Komi Forests" and Belovezhskaya Pushcha are on the World Heritage List.

Lit. : Spiridonov A.I. Geomorphological zoning of the East European Plain // Zemlevedenie. M., 1969. T. 8; Plains of the European part of the USSR / Edited by Yu. A. Meshcheryakov, A. A. Aseev. M., 1974; Milkov F.N., Gvozdetsky N.A. Physical Geography of the USSR. General review. European part of the USSR. Caucasus. 5th ed. M., 1986; Isachenko A.G. Ecological geography of the North-West of Russia. SPb., 1995. Part 1; Eastern European forests: history in the Holocene and the present: In 2 vols. M., 2004.

A. N. Makkaveev, M. N. Petrushina.

Relief, history of development

Geo-structurally, the East European Plain basically corresponds to the East European Platform. At its base, there are strongly dislocated crystalline rocks that protrude onto the day surface within the Baltic and Ukrainian shields. In the rest of the much larger part of the platform, crystalline rocks are hidden under a layer of gently sloping sedimentary rocks that compose the Russian Plate. The southern part of the East European Plain (from the Azov to the Caspian Seas) corresponds to the Scythian plate, where rocks of the strongly dislocated Hercynian basement lie under the cover of platform sedimentary formations.

The East European Plain is divided into two unequal parts: the base-denudation plain on the Baltic crystalline shield and the Russian Plain proper with layer erosion-denudation and accumulative relief on the Russian and Scythian plates. Basement-denudation lowlands and uplands on the Baltic Shield with heights of up to 300-600 m (Manselka, Suomenselka, West Karelian, etc.) include areas of massive hills and plateaus with heights of more than 1,000 m (massif up to 1,190 m). The relief of the shield arose as a result of prolonged continental denudation and preparation of structural forms composed of relatively strong rocks. Direct impact the relief was influenced by tectonic movements of recent times, especially the faults limiting massifs and depressions, river valleys and depressions of numerous lakes. In Anthropogenic times, the territory of the Baltic Shield served as a center of glaciation, therefore fresh forms of glacial relief are widespread here.

Within the boundaries of the Russian Plain proper, a thick cover of platform sediments lies almost horizontally, composing accumulative and stratal-denudational lowlands and uplands, mainly corresponding to depressions and rises of the folded base. In some places, the folded foundation protrudes to the surface, forming basement-denudation heights and ridges (Dnieper and Azov Uplands, Timansky and Donetsky ridges).

Average height The Russian Plain is about 170 m. The lowest heights are on the coast of the Caspian Sea, the level of which is 27.6 m lower. Uplands rise up to 300-350 m above sea level (Podolsk Upland, up to 471 m). The relative excess of the watersheds over the valleys is, on average, 20-60 m.

The Russian plain is subdivided into three morphological zones. In the northern part, there are stratal denudation lowlands and uplands of pre-anthropogenic age with superimposed relief forms of glacial and water-glacial origin. Glacial-accumulative forms are most pronounced in the northwest, in the area of ​​the last (Valdai) glaciation, where hilly ridges and uplands stretch: Baltic, Valdai, Vepsovskaya, Belozerskaya, Konoshsko-Nyandomskaya. This is a region of Poozerie with a characteristic abundance of lakes (Kubenskoe, Vozhe, etc.).

To the south, southeast and east stretches an area that was exposed only to more ancient glaciations, where the original glacial-accumulative relief was reworked by erosion-denudation processes. Moraine erosional hills and ridges (Belorussian, Smolensk-Moscow, Borisoglebskaya, Danilevskaya, Galichsko-Chukhlomskaya, Onego-Dvinskaya, Dvinsko-Mezenskaya, Northern Uvaly) alternate with extensive moraine, outwash, lacustrine-glacial and alluvial lowland -Mezenskaya, Pechora, etc.).

To the south, there is a zone of erosion-denudation stratal-monoclinal uplands and accumulative lowlands, elongated mainly in the meridional and submeridional directions and caused by the alternation of waves of the latest uplifts and relative subsidence. In the direction from the south-west to the north-east, the following uplands are traced: Bessarabskaya, Volynskaya, Podolskaya, Pridneprovskaya, Priazovskaya, Ergeni, upland, Poduralskoe plateau. Uplands alternate with outwash and alluvial-terraced low-lying plains: Pripyat, Dnieper, Gorky Trans-Volga, Meshcherskaya, Oksko-Don, Ulyanovsk and Saratov Trans-Volga regions.

In the extreme south and southeast of the East European Plain, there is a strip of coastal lowlands that experienced tectonic subsidence and partial submersion under sea level in the Neogene and Anthropogenous. The original flat-level relief of sea accumulation here has been reworked to varying degrees by the processes of water erosion and loess accumulation (Black Sea lowland), alluvial-proluvial accumulation (Azov-Kuban lowland), fluvial and aeolian processes ().

Hydrography

Hydrographically, the territory of the East European Plain is divided into two parts. Most of them have drainage to the ocean. Northern rivers (,) belong to the basin, western and southern rivers belong to the basin. The latter include rivers flowing into the Baltic (, rivers and), Black (,) and Azov () seas. Rivers of basins, and some others flow into, has lost contact with.

Climate

Most of the East European Plain belongs to the region of the temperate zone, where there is a gradual transition from a maritime climate to a continental one. Westerly winds prevail. The influence of the air masses of the Atlantic Ocean weakens from the northwest to the southeast, and therefore excessive moisture is observed in the north and northwest, sufficient moisture in the central zone and insufficient moisture in the southeast. The extreme north of the East European Plain belongs to the subarctic belt with a predominance of moderate summer and winter arctic types of air masses, with significant seasonal fluctuations in air temperature, with the development of permafrost rocks and soils. In the extreme southeast of the plain, the climate is continental, arid, with large seasonal fluctuations in air temperature

Natural areas

The East European Plain is characterized by a distinctly expressed natural zoning. In a narrow strip of the Barents Sea coast, the subarctic moss-lichen tundra dominates. To the south, there are zones of the temperate zone. The most significant strip of forests, stretching from and to. Along the line - it is divided into dark coniferous taiga and mixed (coniferous-deciduous) forests, passing in the extreme south-west of the plain into broad-leaved forests. To the south, from the Carpathians to the Urals, there is a forest-steppe zone, beyond which it extends to the Black and Azov Seas and to the Caucasus. steppe zone... The vast territory of the Caspian lowland and the Subural plateau is occupied by semi-deserts and deserts.

NATURAL ZONES OF RUSSIA

EASTERN EUROPEAN (RUSSIAN) PLAIN

See photos of the nature of the East European Plain: Curonian Spit, Moscow Region, Kerzhensky Reserve and the Middle Volga in the Nature of the World section of our website.

The East European (Russian) Plain is one of the largest plains in the world in terms of area. Among all the plains of our Motherland, only it comes out to two oceans. Russia is located in the central and eastern parts of the plain. It stretches from the coast of the Baltic Sea to the Ural Mountains, from the Barents and White Seas to the Azov and Caspian Seas.

The East European Plain has the highest rural population density, large cities and many small towns and urban-type settlements, various Natural resources... The plain has long been mastered by man.

The following signs serve as the rationale for its determination to the rank of a physico-geographical country: 1) an uplifted stratal plain formed on the plate of the ancient East European platform; 2) Atlantic-continental, predominantly moderate and insufficiently humid climate, formed largely under the influence of the Atlantic and Arctic oceans; 3) natural zones are clearly expressed, the structure of which was greatly influenced by the flat relief and neighboring territories - Central Europe, North and Central Asia. This led to the interpenetration of European and Asian species of plants and animals, as well as to a deviation from the latitudinal position of natural zones in the east to the north.

Relief and geological structure

The East European elevated plain consists of elevations with heights of 200-300 m above sea level and lowlands along which large rivers flow. The average height of the plain is 170 m, and the highest - 479 m - on Bugulma-Belebey Upland in the Urals part. Maximum elevation Timan ridge slightly less (471 m).

According to the peculiarities of the orographic pattern, three stripes are clearly distinguished within the East European Plain: central, northern and southern. Through the central part of the plain runs a strip of alternating large hills and lowlands: Central Russian, Volga, Bugulma-Belebey Uplands and Common Syrt divided Oka-Don lowland and the Low Trans-Volga region, along which the Don and Volga rivers flow, carrying their waters to the south.

To the north of this strip, low plains prevail, on the surface of which, here and there, smaller uplands are scattered here and there in garlands and singly. From west to east-northeast, they stretch here, replacing each other, Smolensk-Moscow, Valdai Uplands and Northern Uvaly... They are mainly used for watersheds between the Arctic, Atlantic and internal (closed-drainage Aral-Caspian) basins. From the Northern Ridges, the territory goes down to the White and Barents Seas. This part of the Russian Plain A.A. Borzov called the northern slope. Large rivers flow along it - Onega, Northern Dvina, Pechora with numerous high-water tributaries.

The southern part of the East European Plain is occupied by lowlands, of which only the Caspian region is located on the territory of Russia.

Rice. 25. Geological profiles across the Russian Plain

The East European Plain has a typical platform relief, which is predetermined by the tectonic features of the platform: the heterogeneity of its structure (the presence of deep faults, ring structures, aulacogens, anteclises, syneclises and other smaller structures) with unequal manifestation of the latest tectonic movements.

Almost all large uplands and lowlands of the plain are of tectonic origin, with a significant part inherited from the structure of the crystalline basement. In the course of a long and complex path of development, they were formed as a single territory in the morphostructural, orographic and genetic relations.

At the base of the East European Plain lie Russian plate with Precambrian crystalline basement and northern edge in the south Scythian plate with a Paleozoic folded basement. The border between the slabs is not expressed in the relief. On the uneven surface of the Precambrian basement of the Russian Plate, there are strata of Precambrian (Vendian, in places Riphean) and Phanerozoic sedimentary rocks with slightly disturbed bedding. Their thickness is not the same and is due to the unevenness of the basement relief (Fig. 25), which determines the main geostructures of the slab. These include syneclises - areas of deep basement (Moscow, Pechora, Caspian, Glazovskaya), anteclises - areas of shallow basement (Voronezh, Volga-Ural), aulacogenes - deep tectonic ditches, in the place of which syneclises subsequently appeared (Kresttsovsky, Soligalichsky, Moskovsky, etc.), protrusions of the Baikal basement - Timan.

The Moscow syneclise is one of the most ancient and complex internal structures of the Russian plate with a deep crystalline basement. It is based on the Central Russian and Moscow aulacogens, filled with thick Riphean strata, above which the sedimentary cover of the Vendian and Phanerozoic (from the Cambrian to the Cretaceous) lies. In the Neogene-Quaternary period, it experienced uneven uplifts and is expressed in relief by rather large uplands - Valdai, Smolensk-Moscow and lowlands - Upper Volga, North-Dvina.

The Pechora syneclise is located wedge-shaped in the northeast of the Russian plate, between the Timan ridge and the Urals. Its uneven block foundation is lowered to various depths - up to 5000-6000 m in the east. The syneclise is filled with a thick stratum of Paleozoic rocks overlain by Meso-Cenozoic sediments. In its northeastern part there is the Usinsky (Bolshezemelsky) vault.

In the center of the Russian plate there are two large anteclises - Voronezh and Volga-Ural separated by Pachelm aulacogen... The Voronezh anteclise slopes gently to the north into the Moscow syneclise. The surface of its basement is covered with thin Ordovician, Devonian and Carboniferous deposits. Carboniferous, Cretaceous and Paleogene rocks occur on the southern steep slope. The Volga-Ural anteclise consists of large uplifts (arches) and depressions (aulacogenes), on the slopes of which flexures are located. The thickness of the sedimentary cover here is at least 800 m within the highest vaults (Tokmovsky).

The Caspian marginal syneclise is a vast area of ​​deep (up to 18-20 km) subsidence of the crystalline basement and belongs to structures of ancient origin, almost on all sides of the syneclise it is bounded by flexures and faults and has angular outlines. From the west it is framed by the Ergeninskaya and Volgograd flexures, from the north - flexure of Obshchy Syrt. In some places they are complicated by young faults. In the Neogene-Quaternary, further subsidence (up to 500 m) and the accumulation of a thick layer of marine and continental sediments took place. These processes are combined with fluctuations in the level of the Caspian.

The southern part of the East European Plain is located on the Scythian Epigercyn Plate, which lies between the southern edge of the Russian Plate and the Alpine folded structures of the Caucasus.

Tectonic movements of the Urals and the Caucasus have led to some disruption in the occurrence of sedimentary plate deposits. This is expressed in the form of dome-shaped uplifts, significant along the length of the swells ( Oksko-Tsniksky, Zhigulevsky, Vyatsky and others), individual flexural bends of layers, salt domes, which can be clearly traced in the modern relief. Ancient and young deep faults, as well as ring structures, determined the block structure of the plates, the direction of river valleys, and the activity of neotectonic movements. The predominant direction of the faults is northwest.

A brief description of the tectonics of the East European Plain and a comparison of the tectonic map with the hypsometric and neotectonic maps allow us to conclude that the modern relief, which has undergone a long and complex history, is in most cases inherited and dependent on the nature of the ancient structure and manifestations of neotectonic movements.

Neotectonic movements on the East European Plain manifested themselves with different intensity and direction: in most of the territory they are expressed by weak and moderate uplifts, low mobility, and the Caspian and Pechora lowlands experience weak subsidence (Fig. 6).

The development of the morphostructure of the north-west of the plain is associated with the movements of the marginal part of the Baltic shield and the Moscow syneclise; therefore, there are developed monoclinal (inclined) bed plains, expressed in orography in the form of hills (Valdai, Smolensk-Moscow, Belorusskaya, Northern Uvaly, etc.), and stratal plains occupying a lower position (Verkhnevolzhskaya, Meshcherskaya). The central part of the Russian Plain was influenced by the intense uplifts of the Voronezh and Volga-Ural anteclises, as well as the subsidence of neighboring aulacogens and troughs. These processes contributed to the formation layer-tiered, stepped elevations(Central Russian and Volga) and the Oksko-Don plain. The eastern part developed in connection with the movements of the Urals and the edge of the Russian plate; therefore, a mosaic of morphostructures is observed here. Developed in the north and south accumulative lowlands edge syneclises of the plate (Pechora and Caspian). Alternating between them stratal-tiered uplands(Bugulminsko-Belebeevskaya, General Syrt), monoclinal-bed Uplands (Verkhnekamskaya) and intra-platform folded Timansky ridge.

In the Quaternary, a cooling of the climate in the northern hemisphere contributed to the spread of ice sheets. Glaciers have had a significant impact on the formation of relief, Quaternary sediments, permafrost, as well as on changes in natural zones - their position, floristic composition, fauna and migration of plants and animals within the East European Plain.

Three glaciations are distinguished on the East European Plain: Okskoe, Dnieper with the Moscow stage, and Valdai. Glaciers and fluvioglacial waters created two types of plains - moraine and outwash. Permafrost processes prevailed in the wide periglacial (preglacial) belt for a long time. Snowfields had an especially intense effect on the relief during the period of reduced glaciation.

Morena of the most ancient glaciation - Oksky- was studied on the Oka, 80 km south of Kaluga. The lower, heavily washed-out Oka moraine with Karelian crystalline boulders is separated from the overlying Dnieper moraine by typical interglacial deposits. In a number of other sections to the north of this section, under the Dnieper moraine, the Oka moraine was also found.

Obviously, the moraine relief that arose in the Oka Ice Age has not survived to our time, since it was first washed out by the waters of the Dnieper (Middle Pleistocene) glacier, and then it was covered by its bottom moraine.

Southern boundary of maximum spread Dniprovsky integumentary glaciations crossed the Central Russian Upland in the Tula region, then descended with the tongue along the Don valley - to the mouth of the Khopr and Medveditsa, crossed the Volga Upland, then the Volga near the mouth of the Sura River, then went to the upper reaches of the Vyatka and Kama and crossed the Ural in the area of ​​60 ° N. In the basin of the Upper Volga (in Chukhloma and Galich), as well as in the basin of the Upper Dnieper above the Dnieper moraine, the upper moraine occurs, which is attributed to the Moscow stage of the Dnieper glaciation *.

Before the last Valdai glaciation in the interglacial epoch, the vegetation of the middle zone of the East European Plain had a more thermophilic composition than the modern one. This testifies to the complete disappearance of its glaciers in the north. In the interglacial epoch, peat bogs with Brazen flora were deposited in lacustrine basins formed in depressions of the moraine relief.

In the north of the East European Plain, the boreal ingression arose during this era, the level of which was 70-80 m above the present-day sea level. The sea penetrated along the river valleys of the Northern Dvina, Mezen, Pechora, creating wide branching bays. Then came the Valdai glaciation. The edge of the Valdai ice sheet was located 60 km north of Minsk and went to the northeast, reaching Nyandoma.

In the climate of the more southern regions, due to glaciation, there have been changes. At this time, in the more southern regions of the East European Plain, remnants of seasonal snow cover and snowfields contributed to the intensive development of nivation, solifluction, and the formation of asymmetric slopes in erosional landforms (ravines, gullies, etc.).

Thus, if ice existed within the distribution of the Valdai glaciation, then in the periglacial zone a nival relief and sediments (boulderless loams) were formed. The non-glacial, southern parts of the plain are overlain by thick strata of loess and loess-like loams, synchronous with the ice ages. At this time, in connection with the humidification of the climate, which caused glaciation, and also, possibly, with neotectonic movements in the basin of the Caspian Sea, marine transgressions took place.