Plains of the Plains
areas of the land surface, the bottom of oceans and seas, characterized by slight fluctuations in heights. On land, there are plains below sea level, lowland (up to 200 m), elevated (from 200 to 500 m) and mountainous (above 500 m). According to the structural principle, plains of platform and orogenic (mountain) regions are distinguished (mainly within intermountain and foothill troughs); according to the predominance of certain external processes - denudation, formed as a result of the destruction of elevated relief forms, and accumulative, resulting from the accumulation of layers of loose sediments. Collectively, plains occupy most of the Earth's surface. The greatest plain in the world is the Amazon (over 5 million km 2).
PLAINSPLAINS, areas of the land surface, the bottom of oceans and seas, characterized by slight fluctuations in heights. On land there are plains that lie below sea level (cm. SEA LEVEL), lowland (height up to 200 m), elevated (from 200 to 500 m) and mountainous (above 500 m). According to the structural principle, plains of platform and orogenic (mountain) regions are distinguished (mainly within intermountain and foothill troughs); according to the predominance of certain external processes - denudation, formed as a result of the destruction of elevated relief forms, and accumulative, resulting from the accumulation of layers of loose sediments. Collectively, plains occupy most of the Earth's surface. The greatest plain in the world is the Amazon (over 5 million km 2).
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PLAINS, vast, fairly level areas earth's surface. They occupy 15-20% of the land. Height fluctuations within their limits do not exceed 200 m, and slopes are less than 5°. Plains is one of essential elements relief of both land and the bottom of seas and oceans.
Types of land plains
Numerous types of plains are distinguished by the nature and height of the surface, geological structure, origin and history of development.
Depending on the appearance and size of the irregularities, they are divided into: flat, wavy, ridge, stepped and other plains.
Based on the shape of the surface there are: horizontal (Great Chinese Plain (cm. GREAT PLAIN OF CHINA)), inclined (mainly foothills) and concave (plains of intermountain depressions - Tsaidam Basin (cm. TSAIDAM BATTLE)) plains.
The classification of plains by height relative to sea level is widespread. Negative plains are located below sea level, often in deserts, for example, the Qattara Depression (cm. KATTARA) or the lowest place on land - the Ghor depression (cm. GHOR)(up to 395 m below sea level). The lowland plains, or lowlands (altitudes from 0 to 200 m above sea level), include the greatest plains in the world: the Amazonian lowland (cm. AMAZON LOWLANDS), The East European Plain (cm. THE EAST EUROPEAN PLAIN) and West Siberian Plain (cm. WEST SIBERIAN PLAIN). The surface of elevated plains, or hills, is located in the altitude range of 200-500 m (Central Russian Upland (cm. CENTRAL RUSSIAN HIGHWAY), Valdai Upland (cm. VALDAI HIGHWAY)). Mountain plains rise above 500 m, for example, one of the largest in Central Asia - the Gobi (cm. GOBI (a strip of deserts and semi-deserts in Mongolia)). The term plateau is often applied to both elevated and mountainous plains with a flat or undulating surface, separated by slopes or ledges from lower neighboring areas (cm. PLATEAU).
Role of external processes
The appearance of the plain depends largely on external processes. Based on the amount of influence of external processes, plains are divided into accumulative and denudative. Accumulative plains formed during the accumulation of layers of loose sediments (see accumulation (cm. ACCUMULATION)), are river (alluvial), lake, sea, ash, glacial, water-glacial, etc. For example, the thickness of sediments, mainly river and sea, in the Flanders Lowland (North Sea coast) reaches 600 m, and the thickness of silty rocks ( loess ( cm. LOESS) ) on the Loess Plateau (cm. LOESS PLATEAU)- 250-300 m. Accumulative plains also include volcanic plateaus composed of solidified lavas and loose products of volcanic eruptions (Dariganga plateau in Mongolia, Colombian plateau (cm. COLOMBIA PLATEAU) in North America).
Denudation plains arose as a result of the destruction of ancient hills or mountains and removal by water, wind, etc. (see denudation (cm. DENUDATION)) of the resulting material. Depending on the predominant process due to which the ancient relief was destroyed and the surface leveled, erosional (with the predominance of the activity of flowing waters), abrasion (created by wave processes on the sea coasts), deflationary (leveled by the wind) and other denudation plains are distinguished. Many plains have complex origins, as they were formed by various processes. Depending on the mechanism of formation, denudation plains are divided into: peneplains - in this case, the removal and demolition of material occurred more or less evenly from the entire surface of ancient mountains, for example, the Kazakh small hills (cm. KAZAKH SMALL HUMPS) or syrty of the Tien Shan; pediplains that arise from the destruction of previously elevated relief, which begins from the outskirts (many plains at the foot of the mountains, mainly deserts and savannas of Africa, etc.).
The role of internal processes
The participation of tectonic processes in the formation of plains can be either passive or active. With passive participation, the main role in the formation of structural plains is played by a fairly even - horizontal or inclined (monoclinal) - occurrence of rock layers (see Turgai Plateau (cm. TURGAI PLATEAU)). Many structural plains are simultaneously accumulative, for example, the Caspian Lowland (cm. CASPIAN FLOW), North German Lowland (cm. NORTH GERMAN LOWLANDS). When denudation predominates in the formation of structural plains, strata plains are distinguished (Swabian-Franconian Jura (cm. Swabian-Franconian Jura)). What differs from them are the basement plains, developed in dislocated rocks (Lake Plateau in Finland).
During intermittent tectonic uplifts, followed by a period of rest sufficient to destroy and level the relief, tiered plains are formed, for example, the Great Plains (cm. GREAT PLAINS).
Geological typing principle
Platform plains are formed in areas of relatively quiet tectonic and magmatic activity. These include most of the plains, including the largest ones. Plains of orogenic regions (see orogen (cm. OROGEN)) are characterized by intense activity of the earth's interior. These are the plains of intermountain basins ( Fergana Valley (cm. FERGHANA VALLEY)) and foothill troughs (Podolsk Upland (cm. PODILSKY HIGHWAYS)). Sometimes the plains are considered parts of the so-called lowland countries - vast spaces where small areas with highly dissected relief (for example, Zhiguli (cm. ZHIGULI) on the Russian Plain (cm. RUSSIAN PLAIN)- flat country).
Land plains are the most favorable for comprehensive human development. They are home to the majority of the world's population. The largest tracts of forests and arable land with the most fertile soils are concentrated here, deep rivers flow and large lakes are located. Oil, gas, coal, salts and other minerals are extracted on accumulative plains. However, part of the plains has an arid climate and is occupied by giant deserts - Kyzylkum (cm. KYZYL KUM) and Karakum on the Turan Lowland (cm. Turanian Lowland), Great Sandy Desert (cm. GREAT SANDY DESERT) and Great Victoria Desert (cm. GREAT VICTORIA DESERT) on the Western Plateau of Australia, etc.
Types of underwater plains
Among the underwater plains, two types are most common: continental shallows and deep-sea abyssal plains. (cm. ABYSSAL PLAINS). Continental shoal or shelf (cm. SHELF), usually extends from the coast to depths of 200 m and occupies the underwater margins of continents (cm. UNDERWATER EDGE OF THE CONTINENT). The most extensive shoals, more than 1000 km wide, are located on the northern edges of Eurasia and North America. Deep-sea abyssal plains (wavy, flat, hilly) occupy huge basins - the ocean floor and the depressions of the transition zone (cm. TRANSITION ZONE) at depths of 3000-7000 m. Abyssal plains are especially numerous in the Atlantic Ocean; the largest of them are the Som and Demerera plains (cm. DEMERARA).
encyclopedic Dictionary. 2009 .
See what “plains” are in other dictionaries:
Areas of the land surface, the bottom of oceans and seas, characterized by slight fluctuations in heights. On land, there are plains below sea level, lowland (up to 200 m), elevated (from 200 to 500 m) and mountainous (above 500 m). By… … Big Encyclopedic Dictionary
R. differ from uplands in that they are located on low altitude above sea level. It can be approximately assumed that the plains are below 150 soots. or 300 m., or 1000 rus. ft. above sea level, and the highlands are higher. Similar to what has already been noticed... ... Encyclopedia of Brockhaus and Efron
PLAINS, areas of the land surface, the bottom of oceans and seas, characterized by small slopes and slight fluctuations in elevation. On land, there are plains below sea level, lowland (height up to 200 m), elevated (200,500 m) and mountainous... ... Modern encyclopedia
The rivers differ from the highlands (see) in that they are located at a low altitude above sea level. It can be approximately assumed that the plains are below 150 soots. or 300 m, or 1000 rus. ft. above sea level, and the highlands are higher. Similar to what already... Encyclopedic Dictionary F.A. Brockhaus and I.A. Efron
Areas of the land surface, the bottom of oceans and seas, characterized by insignificant. fluctuations in altitude. On land, R. are distinguished that lie below level. m., lowland (up to 200 m), elevated (from 200 to 500 m) and mountainous (above 500 m). According to the structural principle... ... Natural science. encyclopedic Dictionary
Plains- Plains, in: Great Plains (plateau) ... Russian spelling dictionary
- (English Sto Plains) a fictional area in the Discworld book series by Terry Pratchett. Contents 1 general characteristics 2 Cities and countries of the plain Sto 2.1 Sto Lat ... Wikipedia
Lichkov, 1935, vast plains that arise during the era of the existence of high-water streams fed by melting glaciers (for example, Polesie, Meshcherskaya lowland, etc.). Like the great accumulative plains, they are confined to the tect. deflections. Term... ... Geological encyclopedia
There are many places on our planet that are of interest not only to researchers and scientists, but also to ordinary travelers. This high mountains, wild rivers. But in this article we will introduce you to the great plains of the world. Do not think that these vast territories are not very interesting to study. After reading our article, you will understand that this opinion is wrong.
Where are the Great Plains?
Boundless high plateaus are located between the Cordilleras in the west and the Central Plains in the east. The researchers gave the name to this territory - the Great Plains. Mainland North America It is also famous for its Central Plains, but the Great Plains are distinguished by their absolute heights, dry climate and thickness of sedimentary rocks. Under the thickness of loess-like rocks and forests lie layers of Paleogene and Cretaceous rocks. Since predominantly steppe vegetation dominates here, the Great Plains are often called the Prairie Plateau.
The continental climate, position (rather high) above sea level, and easy erosion of soils became the reasons for the development of erosion processes in these territories. Most characteristic relief - ravines. Erosion sometimes reaches gigantic proportions - thousands of hectares at one time fertile soil turn into badlands.
Great Plains: dimensions
This foothill plateau in Canada and the United States is located east of the Rocky Mountains. Its height is from 800 to 1,700 meters above sea level. Length - three thousand six hundred kilometers. Width - from five hundred to eight hundred kilometers. The map shows that this is a huge territory - the Great Plains. Their area is 1,300,000 square kilometers.
Relief
The plains stretch for 3600 km from north to south. They represent a heterogeneous territory. On Canadian soil (the Saskatchewan River basin) is their northern part - the Alberta Plateau. Moraine landforms predominate here. The plateau is distinguished by forest landscapes located on soddy-podzolic soils. There are often individual aspen pegs.
In the Missouri basin (Missouri Plateau), there is an undulating moraine topography with strong erosional dissection, forest-steppe vegetation of aspen and birch copses, separated by forb steppes. This landscape is typical for the Ishim steppe (Southern Siberia). In the middle part of the plateau there is a ridge of terminal moraines.
South of the Missouri Plateau is the High Plains Plateau. These areas are not affected by glaciation; the surface is dissected by rivers, slightly undulating. There is no forest vegetation here - this plateau is dominated by mixed-grass steppe, densely covered with ravines. This part of the Great Plains has been plowed up for a long time, and erosion is particularly progressing here.
Even further south is the Llano Estacado plateau. It has a more leveled relief, which in some places is diluted by karst sinkholes. The vegetation of this plateau is steppe; here you can find single yuccas and columnar cacti.
In the very south of the Great Plains is the Edwards Plateau, which, in its landscape appearance, resembles the neighboring regions of Mexico with its characteristic succulents (yuccas, cacti). This plateau is poorly dissected and is characterized by a predominance of chestnut soils.
Animal world
The Great Plains, whose area is huge, are distinguished by a fairly diverse fauna, which is directly related to the nature of the landscapes. In the northern part you can find steppe bison and pronghorn antelope; in the southern and central regions live the steppe fox, wolf, and prairie dogs. The most common birds are the steppe falcon and the meadow grouse.
Russian Plain
Experts more often call this territory the East European Plain. This is a real natural pantry of Russia. Judge for yourself: in its foundation lie coal, iron ores, oil and natural gas, others useful resources. Its fertile soils, according to experts, can easily feed Russians.
The Great Russian Plain ranks second in area in the world, second only to the Amazon Lowland. It is classified as low plains. This territory is washed by the White and Barents seas in the north, and the Caspian, Azov and Black seas in the south.
Like many other great plains of the world, the Russian one is in the southwest and west and adjacent to the mountains - the Sudetes, the Carpathians, in the northwest it is limited by the Scandinavian Mountains, in the east by the Urals and Mugodzhars, and in the southeast by the Caucasus and Crimean Mountains .
Dimensions
The Russian Plain stretches from east to west for 2.5 thousand kilometers. From south to north - 2750 kilometers. total area territory - five and a half million square kilometers. The maximum height was recorded on Mount Yudychvumchorr (Kola Peninsula - 1191 meters). The lowest point is located on the coast of the Caspian Sea, it is characterized by a minus value of -27 meters.
The following countries are partially or completely located on the territory of the Russian Plain:
- Kazakhstan.
- Belarus.
- Lithuania.
- Latvia.
- Poland.
- Moldova.
- Russia.
- Estonia.
- Ukraine.
Relief
The relief of the Russian Plain is dominated by planes. Similar geographical position It is characterized by rare earthquakes and volcanic activity.
Hydrography
The main part of the waters of the Russian Plain has access to the ocean. The southern and western northern regions flow into the Arctic Ocean. The northern rivers include the Onega, Mezen, and Northern Dvina Pechora. Southern and western rivers carry their waters to the Vistula, Neman, Neva, etc. The Dniester and Dnieper, the Southern Bug flow into the Black Sea, and the Don into the Azov Sea.
Climate
The Russian Plain has a temperate continental climate. Average summer temperatures can range from -12 degrees (in the Barents Sea area) to +25 degrees (in the Caspian Lowland). Maximum winter temperatures are recorded in the west. In these areas the air temperature does not drop below -3 degrees. In Komi this figure reaches -20 degrees.
Precipitation in the southeast falls up to 400 mm (during the year), in the west their amount doubles. change from semi-desert in the south to tundra in the north.
Chinese plain
Many people have probably heard about this plain, but perhaps not everyone knows where the Great Chinese Plain is located. One of the largest plains in Asia. In the east it is washed by the Yanshan Mountains in the north, and in the west by the Taihangshan Range. Its eastern slopes have steep ledges more than a thousand meters high. In the southwest are the Dabeshan and Tongboshan ranges. The total area of the plain is more than 325 thousand square kilometers.
In the foothill, western part, which is made up of ancient alluvial cones, the plain reaches a height of one hundred meters. Closer to the sea it drops less than fifty meters.
Relief
On the sea coast the plain is almost flat, only slight slopes are noticeable. There are swampy depressions occupied by small lakes. Within the plain are the Shandong Mountains.
Rivers
In addition to the largest river, the Yellow River, the Huaihe and Haihe rivers flow here. They are characterized by rather sharp fluctuations in flow and monsoon regime.
The maximum summer flow often exceeds the spring minimum by almost a hundred times.
Climatic conditions
The Chinese Plain has a monsoon subtropical climate. In winter, dry and cold air dominates here, which comes from Asia. In January average temperature equal to -2...-4 degrees.
In summer the air warms up to +25...+28 degrees. Up to 500 mm of precipitation falls annually in the north and up to 1000 mm in the south.
Vegetation
Today, the forests that previously grew here with an admixture of subtropical evergreens have not been preserved. There are groves of ash, thuja, poplar, and pine.
The soils are mainly alluvial, which have undergone significant changes during agricultural cultivation.
Amazonian lowland
This is the greatest plain in the world. It covers an area of more than 5 million square kilometers. Its maximum height is 120 meters.
Vast areas of the lowlands are inextricably linked with the life of the Amazon River, the largest drainage area in the world. A huge part of its territory near the river floodplain is regularly flooded, resulting in the formation of swampy areas (marches).
- Lowland is a plain that rises no higher than 200 m above sea level.
- Highlands are flat areas of land with an altitude of 200 to 500 meters above sea level.
- A plateau is a plain with a flat or slightly undulating surface, elevated above sea level by more than 500 meters.
Accumulation
Seabed rise
Change of plains under the influence of water flows
Just like the mountains, the plains gradually change. Much work is done on them by water flows, both permanent (rivers) and temporary, which form on the slopes after heavy rains or during the spring snow melt.
Each tributary of the river digs out a valley through which it flows, each tributary erodes the banks and deepens, albeit slowly, its bed. The process of erosion occurs especially quickly on hills and plateaus, since the rivers originating from them have a more rapid flow.
Water flowing over the surface washes away the top, arable layer of soil from the fields along with nutrients, which are so necessary for plants. Flushing occurs especially quickly on steep slopes, not covered with vegetation; that's why steep slopes are not plowed. Slopes with a slight slope should only be plowed across. When plowing a slope transversely, the flowing water is retained by the furrows, absorbed into the ground and does not wash away the soil. Thus, millions of hectares of fertile soil are preserved from erosion. Material from the site
Changing plains under the influence of wind
The winds, sweeping over the plains, do great destructive work. It happens that hurricane-force winds blow over the plains for several days in a row, without ceasing. A dust storm begins. In one such storm, the wind can remove a layer of soil up to 25 cm thick, and previously fertile lands turn into barren wastelands.
Grass strips, which are created at certain intervals in the fields, reduce soil blowing, as well as forest strips.
The wind does especially great work on plains covered shifting sands, not fastened by the roots of plants - dunes and dunes. The open expanse of sand is never level.
Plains- vast areas of the earth's surface with small (up to 200 m) fluctuations in height and slight slopes.
Plains occupy 64% of the land area. Tectonically, they correspond to more or less stable platforms that have not shown significant activity in recent times, regardless of their age - ancient or young. Most of the land's plains are located on ancient platforms (42%).
Plains are distinguished by absolute and surface height negative-
lying below the level of the World Ocean (Caspian), low-lying- from 0 to 200 m altitude (Amazonian, Black Sea, Indo-Gangetic lowlands, etc.), sublime- from 200 to 500 m (Central Russian, Valdai, Volga uplands, etc.). Plains also include plateau (high plains), which, as a rule, are located above 500 m and are separated from the adjacent plains by ledges (for example, the Great Plains in the USA, etc.). The depth and degree of dissection of them by river valleys, gullies and ravines depends on the height of the plains and plateaus: what
The higher the plain, the more intensely they are dissected.
In terms of appearance, plains can be flat, wavy, hilly, stepped, and in terms of the general slope of the surface - horizontal, inclined, convex, concave.
Different appearance plains depends on their origin and internal structure, which largely depend on the direction of neotectonic movements. Based on this feature, all plains can be divided into two types - denudation and accumulative (see diagram 14-A-1-1). Within the former, the processes of denudation of loose material predominate, and within the latter, its accumulation.
It is clear that denudation surfaces have experienced upward tectonic movements for most of their history. It was thanks to them that the processes of destruction and demolition - denudation - prevailed here. However, the duration of denudation may vary, and this is also reflected in the morphology of such surfaces.
With continuous or almost continuous slow (epeirogenic) tectonic uplift, which continued throughout the entire existence of the territories, there were no conditions for the accumulation of sediments. There was only a denudation of the surface by various exogenous agents, and if thin continental or marine sediments accumulated for a short time, then during subsequent uplifts they were carried out of the territory. Therefore, in the structure of such plains, an ancient base comes to the surface - folds cut off by denudation, only slightly covered by a thin cover of Quaternary deposits. Such plains are called basement; It is easy to see that the basement plains tectonically correspond to the shields of ancient platforms and the protrusions of the folded foundation of young platforms. Basement plains on ancient platforms have a hilly topography, most often they are elevated. These are, for example, the plains of Fennoscandia - the Kola Peninsula and Karelia. Similar plains are located in northern Canada. Basement hills are widespread in Africa. As a rule, long-term denudation has cut off all the structural irregularities of the base, so such plains are astructural.
The plains on the “shields” of young platforms have a more “restless” hilly topography, with residual elevations such as hills, the formation of which is associated either with lithological features - more
hard stable rocks, or with structural conditions - former convex folds, microhorsts or exposed intrusions. Of course, they are all structurally determined. This is what, for example, the Kazakh small hills and part of the Gobi plains look like.
Plates of ancient and young platforms, experiencing a stable uplift only during the neotectonic stage of development, are composed of layers of sedimentary rocks of great thickness (hundreds of meters and a few kilometers) - limestones, dolomites, sandstones, siltstones, etc. Over millions of years, the sediments hardened, became rocky and acquired stability to erosion. These rocks lie more or less horizontally, as they were once deposited. Uplifts of territories during the neotectonic stage of development stimulated denudation on them, which did not allow young loose rocks to be deposited there. Plains on slabs of ancient and young platforms are called reservoir. From the surface, they are often covered with loose Quaternary continental sediments of low thickness, which practically do not affect their height and orographic features, but determine them appearance due to morphosculpture (East European, southern part of West Siberian, etc.).
Since strata plains are confined to platform plates, they are clearly structural - their macro- and even mesoforms of relief are determined by the geological structures of the cover: the nature of the bedding of rocks of varying hardness, their slope, etc.
During the Pliocene-Quaternary subsidence of territories, even relative ones, sediments carried away from surrounding areas began to accumulate on them. They filled in all the previous surface irregularities. This is how they were formed accumulative plains, composed of loose, Pliocene-Quaternary sediments. These are usually low-lying plains, sometimes even below sea level. According to the conditions of sedimentation, they are divided into marine and continental - alluvial, aeolian, etc. An example of accumulative plains are the Caspian, Black Sea, Kolyma, Yana-Indigirsk lowlands composed of marine sediments, as well as the Pripyat, Leno-Vilyui, La Plata, etc. Accumulative plains , as a rule, are confined to syneclises.
In large basins among the mountains and at their feet, accumulative plains have a surface inclined from the mountains, cut through by the valleys of many rivers flowing from the mountains and complicated by their alluvial cones. They are more complex
We are filled with loose continental sediments: alluvium, proluvium, colluvium, and lake sediments. For example, the Tarim Plain is composed of sands and loess, the Dzungarian Plain is composed of powerful sand accumulations brought from neighboring mountains. The ancient alluvial plain is the Karakum desert, composed of sands brought by rivers from the southern mountains in the pluvial era of the Pleistocene.
The morphostructures of plains usually include ridges These are linearly elongated hills with rounded peaks, usually no more than 500 m high. They are composed of dislocated rocks of different ages. An indispensable feature of a ridge is the presence of a linear orientation, inherited from the structure of the folded region in the place of which the ridge arose, for example, Timansky, Donetsk, Yenisei.
It should be noted that all of the listed types of plains (basement, strata, accumulative), as well as plateaus, plateaus and ridges, according to I. P. Gerasimov and Yu. A. Meshcheryakov, are not morphographic concepts, but morphostructural ones, reflecting the relationship of relief with geological structure 1.
Plains on land form two latitudinal series corresponding to the platforms of Laurasia and Gondwana. Northern Plains Row formed within relatively stable limits modern times the ancient North American and East European platforms and the young EpiPaleozoic West Siberian platform - a plate that experienced even a slight subsidence and is expressed in relief as a predominantly low-lying plain.
The Central Siberian plateau, and in the morpho-structural sense these are high plains - a plateau, was formed on the site of the ancient Siberian platform, activated in recent times due to resonant movements from the east, from the active geosynclinal Western Pacific belt. The so-called Central Siberian Plateau includes volcanic plateaus(Pu-torana and Syverma), tuffaceous plateaus(Central Tunguska), trap plateaus(Tungusskoye, Vilyuiskoye), reservoir plateaus(Priangarskoe, Prilenskoe), etc.
The orographic and structural features of the plains of the northern row are peculiar: beyond the North-
“Plateaus and plateaus are often distinguished only by their appearance and degree of dissection, without taking into account their geological structure. Plateaus are considered less dissected forms of relief and are classified as high plains. Plateaus are usually higher, dissected more intensely and deeper in the marginal parts, so they are classified as mountains.
The Arctic Circle is dominated by low coastal accumulative plains; to the south, along the so-called active 62° parallel, there is a strip of basement hills and even plateaus on the shields of ancient platforms - Laurentian, Baltic, Anabar; in middle latitudes along 50° N. w. - again a strip of stratal and accumulative lowlands - North German, Polish, Polesie, Meshchera, Sredneobskaya, Vilyuiskaya.
On the East European Plain, Yu. A. Meshcheryakov identified another pattern: the alternation of lowlands and hills. Since the movements on the East European Platform were wave-like in nature, and their source in the neotectonic stage was collisions of the Alpine belt, he established several alternating stripes of hills and lowlands, fanning out from the southwest to the east and taking an increasingly meridional direction as they move away from the Carpathians . The Carpathian strip of uplands (Volyn, Podolsk, Prydneprovskaya) is replaced by the Pripyat-Dnieper strip of lowlands (Pripyat, Prydneprovskaya), followed by the Central Russian strip of uplands (Belarusian, Smolensk-Moscow, Central Russian); the latter is successively replaced by the Upper Volga-Don strip of lowlands (Meshchera lowland, Oka-Don plain), then by the Volga upland, Trans-Volga lowland and, finally, by a strip of the Cis-Ural uplands.
In general, the plains of the northern series are inclined to the north, which is consistent with the flow of the rivers.
Southern Plains Row corresponds to the Gond-Van platforms, which have experienced activation in recent times. Therefore, elevations predominate within its boundaries: stratum (in the Sahara) and basement (in southern Africa), as well as plateaus (Arabia, Hindustan). Only within the inherited troughs and syneclises did stratal and accumulative plains form (Amazonian and La Plata lowlands, the Congo depression, the Central Lowland of Australia).
Generally largest areas among the plains on the continents belong strata plains, within which the primary plain surfaces are formed by horizontally lying layers of sedimentary rocks, and the basement and accumulative plains are of subordinate importance.
In conclusion, we emphasize once again that mountains and plains, as the main forms of relief on land, are created by internal processes: mountains gravitate towards mobile folded belts
Lands, and plains - to platforms (Table 14). Relatively small, relatively short-lived relief forms created by external exogenous
processes overlap
on large ones and give them a unique appearance. They will be discussed below.
Table 14
Areas of the main types of continental morphostructures (%)
Plains and mountains are the main forms of the earth's surface. They were formed as a result of geological processes that have shaped the face of the Earth throughout geological history. Plains are vast spaces with calm, flat or hilly terrain and relatively small fluctuations in relative heights (no more than 200 m).
Plains are divided by absolute height. Plains with an absolute height of no more than 200 m are called lowlands, or lowlands (West Siberian). Plains, the absolute height of which is from 200 to 500 m, are called elevated, or hills (East European, or Russian). Plains whose height is over 500 m above sea level are called high or plateaus (Central Siberian).
Due to their considerable height, plateaus and hills usually have a more dissected surface and rugged terrain compared to lowlands. Elevated plains with flat surface are called plateaus.
The largest lowlands: Amazonian, Mississippian, Indo-Gangetic, German-Polish. represents an alternation of lowlands (Dnieper, Black Sea, Caspian, etc.) and uplands (Valdai, Central Russian, Volyn-Podolsk, Volga, etc.). Plateaus are most widespread in Asia (Central Siberian, Arabian, Deccan, etc.), in (East African, South African, etc.), in (West Australian).
The plains are also divided by origin. On the continents, the majority (64%) of the plains were formed on platforms; They are composed of layers of sedimentary cover. Such plains are called stratal or platform plains. The Caspian lowland is the youngest plain, and is an ancient platform plain, its surface has been significantly modified by flowing waters and other external processes.
The plains that arose as a result of the removal of products of mountain destruction (denudation) from the destroyed base of the mountains (basement) are called denudation, or base, plains. Mountain destruction and transport usually occurs under the influence of water, ice and gravity. Gradually, the mountainous country smoothes out, levels out, turning into a hilly plain. Denudation plains are usually composed of hard rocks (small hills).
The main lowlands and plateaus of the world
| Lowlands | Plateau |
|---|---|
| German-Polish London Pool Parisian pool Central Danube Lower Danube |
Norland Manselka (ridge) Maladeta |
| Mesopotamian Great Chinese Plain Coromandel Coast Malabar coast Indo-Gangetic |
Anatolian Changbai Shan |
| Mississippi Mexican Atlantic Mosquito Beach |
Great Plains Central Plains Yukon (plateau) |
| Amazonian (Selvas) Orinoco (Llanos) La Plata |
Patagonian |
| Central (Great Artesian Basin) Carpentaria |