Northeastern Siberia. Eastern Siberia: minerals and relief Evaluation of the relief of Eastern Siberia

Eastern Siberia is part of the Asian territory of the Russian Federation. Settled away from the borders Pacific Ocean to the Yenisei River. This zone is characterized by an extremely harsh climate and limited fauna and flora.

Geographic Description

Eastern and occupy almost two-thirds of the territory of Russia. They are located on the plateau. The eastern zone covers an area of about 7.2 million square meters. km. Its possessions extend up to the Sayan mountain ranges. Most of the territory is represented by the tundra lowland. The mountains of Transbaikalia play a significant role in the formation of the relief.

Despite the harsh climatic conditions, there are quite a lot of large cities in Eastern Siberia. The most attractive from an economic point of view are Norilsk, Irkutsk, Chita, Achinsk, Yakutsk, Ulan-Ude, and others. Within the zone are the Zabaikalsky and Krasnoyarsk Territories, the republics of Yakutia, Buryatia, Tuva and other administrative regions.

The main type of vegetation is the taiga. It will be washed from Mongolia to the borders of the forest-tundra. Occupies over 5 million sq. km. Most of the taiga is represented by coniferous forests, which make up 70% of the local vegetation. Soils develop unevenly relative to natural zones. In the taiga zone, the soil is favorable, stable, in the tundra - rocky, frozen.

Within the interfluve and lowlands, insignificant swamps are observed. However, they are much less than in the same Western Siberia. But in the eastern region, arctic deserts and deciduous plantations are often found.

Terrain characteristics

Eastern Siberia of Russia is located at a high level above the sea. All the fault of the plateau, which is located in the middle part of the zone. Here the height of the platform varies from 500 to 700 meters above sea level. The relative averageness of the region is noted. The highest points are the interfluve of the Lena and the Vilyui plateau - up to 1700 meters.

The base of the Siberian platform is represented by a crystalline folded basement, on which there are huge sedimentary layers up to 12 kilometers thick. The north of the zone is determined by the Aldan shield and the Anabar massif. The average thickness of the soil is about 30 kilometers.

To date, the Siberian platform contains several main types of rocks. These are marble, and schist, and charnockite, etc. The oldest deposits date back to 4 billion years. Igneous rocks were formed as a result of eruptions. Most of these deposits are located in and also in the Tunguska depression.

The modern relief is a combination of lowlands and uplands. Rivers flow in the valleys, swamps form, coniferous trees grow better on the hills.

Features of the water area

It is generally accepted that the Far East faces the Arctic Ocean with its "facade". The eastern region borders on such seas as the Kara, Siberian and Laptev. Of the largest lakes, it is worth highlighting Baikal, Lama, Taimyr, Pyasino and Khantayskoye.

Rivers flow in deep valleys. The most significant of them are the Yenisei, Vilyui, Lena, Angara, Selenga, Kolyma, Olekma, Indigirka, Aldan, Lower Tunguska, Vitim, Yana and Khatanga. The total length of the rivers is about 1 million km. Most of the inland basin of the region belongs to the Arctic Ocean. Other external water areas include such rivers as Ingoda, Argun, Shilka and Onon.

The main source of nutrition for the inner basin of Eastern Siberia is the snow cover, which melts in large volumes under the influence of sunlight from the beginning of summer. The next most important role in the formation of the continental water area is played by rains and groundwater. The highest level of basin runoff is observed in summer period.

The largest and most important river in the region is the Kolyma. Its water area occupies more than 640 thousand square meters. km. The length is about 2.1 thousand km. The river originates in the Upper Kolyma Highlands. Water consumption exceeds 120 cubic meters per year. km.

Eastern Siberia: climate

The formation of meteorological features of the region is determined by its territorial location. The climate of Eastern Siberia can be briefly described as continental, consistently severe. There are significant seasonal fluctuations in cloudiness, temperature, and precipitation levels. The Asian anticyclone forms vast areas of high pressure in the region, especially this phenomenon occurs in winter time. On the other hand, severe frost makes air circulation changeable. Because of this, temperature fluctuations at different times of the day are more significant than in the west.

Climate Northeast Siberia represented by variable air masses. It is characterized by increased precipitation and dense snow cover. This area is dominated by continental flows, which are rapidly cooling in the ground layer. That is why in January the temperature drops to a minimum. Arctic winds prevail at this time of the year. Often in winter, you can observe air temperatures down to -60 degrees. Basically, such minima are inherent in depressions and valleys. On the plateau, the indicators do not drop below -38 degrees.

Warming is observed with the arrival of air flows from China and Central Asia to the region.

winter time

No wonder it is believed that Eastern Siberia has the heaviest and most severe. The table of temperature indicators in winter is proof of this (see below). These indicators are presented as average values for the last 5 years.

Due to the increased dryness of the air, the constancy of the weather and the abundance sunny days such low rates are more easily tolerated than in a humid climate. One of the defining meteorological characteristics of winter in Eastern Siberia is the absence of wind. Most of the season there is a moderate calm, so there are practically no blizzards and snowstorms here.

Interestingly, in the middle part of Russia, a frost of -15 degrees is felt much stronger than in Siberia -35 C. Nevertheless, such low temperatures significantly worsen the living conditions and activities of local residents. All living quarters have thickened walls. Expensive fuel boilers are used to heat buildings. The weather begins to improve only with the onset of March.

warm seasons

In fact, spring in this region is short, as it comes late. The eastern one, which changes only with the arrival of warm Asian air currents, begins to wake up only by mid-April. It is then that the stability of positive temperatures during the daytime is noted. Warming comes in March, but it is insignificant. By the end of April, the weather begins to change in better side. In May, the snow cover completely melts, the vegetation blooms.

In summer, the weather becomes relatively hot in the south of the region. This is especially true for the steppe zone of Tuva, Khakassia and Transbaikalia. In July, the temperature here rises to +25 degrees. The highest rates are observed on flat terrain. It is still cool in the valleys and highlands. If we take the whole of Eastern Siberia, then the average summer temperature here is from +12 to +18 degrees.

Climate features in autumn

Already at the end of August, the first frosts begin to envelop the Far East. They are observed mainly in the northern part of the region at night. During the day the bright sun shines, it rains with sleet, sometimes the wind intensifies. It is worth noting that the transition to winter is much faster than from spring to summer. In the taiga, this period takes about 50 days, and in the steppe area - up to 2.5 months. All this character traits, which distinguishes Eastern Siberia from other northern zones.

The climate in autumn is also represented by an abundance of rains coming from the west. Moist Pacific winds blow most often from the east.

Precipitation level

Relief is responsible for atmospheric circulation in Eastern Siberia. Both the pressure and the speed of air mass flows depend on it. About 700 mm of precipitation falls annually in the region. The maximum indicator for the reporting period is 1000 mm, the minimum is 130 mm. The level of precipitation is not clearly defined.

On the plateau in the middle lane, it rains more often. Due to this, the amount of precipitation sometimes exceeds the mark of 1000 mm. The most arid region is Yakutsk. Here the amount of precipitation varies within 200 mm. The least rain falls between February and March - up to 20 mm. The western regions of Transbaikalia are considered the optimal zones for vegetation with respect to precipitation.

Permafrost

Today there is no place in the world that could compete in terms of continentality and meteorological anomalies with a region called Eastern Siberia. The climate in some areas is striking in its severity. In the immediate vicinity of the Arctic Circle lies the permafrost zone.

This area is characterized by low snow cover and low temperatures throughout the year. Because of this, mountain weather and the ground lose a huge amount of heat, freezing to whole meters in depth. The soils here are mostly stony. Groundwater is underdeveloped and often freezes for decades.

Vegetation of the region

The nature of Eastern Siberia is mostly represented by taiga. Such vegetation extends for hundreds of kilometers from the Lena River to the Kolyma. In the south, the taiga borders on the local possessions are untouched by man. However, due to the arid climate, the threat of large-scale fires always hangs over them. In winter, the temperature in the taiga drops to -40 degrees, but in summer the figures often rise to +20. Rainfall is moderate.

Also, the nature of Eastern Siberia is represented by the tundra zone. This zone is adjacent to the Arctic Ocean. The soils here are bare, the temperature is low, and the humidity is excessive. Flowers such as cotton grass, gravel, poppy, saxifrage grow in mountainous areas. From the trees of the region, one can distinguish spruces, willows, poplars, birches, pines.

Animal world

Almost all regions of Eastern Siberia are not rich in fauna. The reasons for this are permafrost, lack of food and underdevelopment of deciduous flora.

The largest animals are the brown bear, lynx, elk and wolverine. Sometimes you can meet foxes, ferrets, stoats, badgers and weasels. Musk deer, sable, deer and bighorn sheep live in the central strip.

Because of the eternally frozen soil, only a few species of rodents are found here: squirrels, chipmunks, flying squirrels, beavers, marmots, etc. But the feathered world is extremely diverse: capercaillie, crossbill, hazel grouse, goose, crow, woodpecker, duck, nutcracker, sandpiper, etc. .

It extends from the shores of the Arctic Ocean to the border with Mongolia, from the left bank of the Yenisei to the watershed ranges of the Far East;

It occupies 1/4 of the area of Russia;

Located in middle and high latitudes;

Far from the Atlantic Ocean;

Limited from the influence of the Pacific Ocean by a barrier of mountain ranges on Far East

2. Complete the sentences.

1) The East Siberian region includes the republics of Khakassia, Tyva, Buryatia, the regions of Zabaikalsky and Krasnoyarsk and the Irkutsk region.

2) The relief of Eastern Siberia is dominated by mountains, in the center is the Central Siberian Plateau.

3) The climate is sharply continental.

4) Large rivers Lena, Angara, Nizhnyaya Tunguska, Podkamennaya Tunguska flow through the territory of the district

5) Here is the deepest lake in the world - Baikal.

6) Ores of various metals (copper, nickel, polymetallic, molybdenum, uranium, gold) are mined in Eastern Siberia.

7) The branches of specialization of the district are non-ferrous metallurgy, mechanical engineering, timber industry, and agriculture.

3. Why is transport of particular importance for Eastern Siberia? Give at least 3-4 reasons to support this.

The vast distances of the region can only be overcome with a well-developed transport network. The Trans-Siberian Railway connected Siberia with the center of the country, the Far East and foreign countries. The development of the transport structure will make it possible to explore new mineral deposits. The construction of new highways will lead to the formation of industrial complexes, as well as create new jobs.

4. Using the texts "What was the role of the Trans-Siberian Railway?" (p. 173-174 of the textbook) and "What is BAM?" (p. 182-183 textbook), reveal the importance of the Trans-Siberian and Baikal-Amur highways for Siberia and the country.

The Trans-Siberian Railway, which is called the Great Siberian Way, connected the European part of Russia, the Urals, Siberia and the Far East. The highway played a significant role during the years of the Russo-Japanese War for supplying the army, in addition, it changed the economic situation in Siberia. The Trans-Siberian Railway is important not only for our country, but also for Asian countries, European and American countries.

The Baikal-Amur Mainline was a "backup" of the Trans-Siberian Railway and crossing mountain ranges and numerous rivers on its way, the railway passes north of the Trans-Siberian Railway. Its construction opened the way to the development of new areas and improved transport connection with the Far East.

6. On the contour map (p. 78 of the Appendix):

1) mark the boundaries of the East Siberian region with conventional signs;

2) sign the subjects of the Russian Federation that are part of the East Siberian region.

7. On the contour map (p. 78 of the Appendix), mark and label the main landforms, the largest rivers and lakes, and the minerals of Eastern Siberia.

9. Compare physical and tectonic maps. Explain the structure of the surface of Eastern Siberia.

The tectonic structure of the Central Siberian plateau is confined to the Siberian platform with two shields: Anabar in the north and Aldan in the southeast. 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 difference in the relief is 500-700 meters, but there are parts of the plateau, where the absolute mark rises above 1000 meters, such areas include the Yenisei Ridge. One of the highest parts of the territory is the Putorana Plateau, its height is 1678 m above sea level. Thus, mountainous landforms predominate.

10. Using the map of natural zones, find out the position of the forest-steppe and steppe zones in Eastern Siberia.

1) What is the area compared to the area of the district they occupy? In Eastern Siberia, the steppe occupies intermountain basins (Minusinsk, Tuva).

2) What is their area compared to the area of similar zones in the Central Black Earth Region and in the European South? The area is insignificant, since these zones do not form a continuous strip as in the Chernozem region and in the European south.

11. Academician V. A. Obruchev studied Eastern Siberia. Using additional literature available in the home, school or district library, the resources of the free encyclopedia "Wikipedia" on the Internet:

1) study the biography of the scientist;

2) find out what he did and what discoveries he made;

3) establish which geographical objects are named after him;

4) make a list of books written by him.

1) Vladimir Obruchev was born on October 10, 1863 in the village of Klepenino, now the Kalinin region. In 1886 he graduated from the Mining Institute in St. Petersburg. Was a professor at Tomsk Institute of Technology(1919-1921), Tauride University in Simferopol (1918-1919) and the Moscow Mining Academy (1921 - 1929). Since 1930 he has been chairman of the Commission (Committee) for the study of permafrost, since 1939 he has been director of the Institute of Permafrost Science of the USSR Academy of Sciences. In 1942-1946, Academician-Secretary of the Department of Geological and Geographical Sciences of the USSR Academy of Sciences.

2) Vladimir Obruchev is a well-known researcher of the geology of Siberia, Central and Central Asia. In the 80-90s of the 19th century, his work was associated with the design of the Trans-Caspian and Trans-Siberian railways. The main works of Obruchev are connected with the solution of the following problems: the origin of loess in Central and Central Asia; glaciation and permafrost in Siberia; general questions of tectonics and tectonic structure of Siberia; proposed the term "neotectonics"; geology of gold deposits in Siberia; the existence of the "ancient crown" of Asia.

3) In the name of V.A. Obruchev are named: a mountain range in the Tyva Republic, a mountain in the upper Vitim, an oasis in Antarctica and other geographical objects, as well as the mineral obruchevite, a hydrated uranium-yttrium variety of pyrochlore.

4) List of books by V.A. Obruchev:

1. Monographs: "Geology of Siberia" (1935-1938), "History of the geological exploration of Siberia" (vols. 1-5, 1931-1959);

2. Textbooks: "Field geology" (vols. 1-2, 1927), "Ore deposits" (parts 1 - 2, 1928-29);

3. Popular science books: "Formation of mountains and ore deposits" (1932), "Fundamentals of Geology" (1944);

4. Science fiction novels: "Plutonia" (1915, published in 1924), "Sannikov Land" (1924, published in 1926), "Gold Diggers in the Desert" (1928), "In the Wilds of Central Asia" (1951).

Make a conclusion: what is the scientist's contribution to the development of geological and geographical science? V.A. Obruchev substantiated the concept of vertical movements earth's crust and their role in the modern relief of Siberia, proposed the term "neotectonics", compiled a summary of data on gold deposits, a forecast for prospecting for gold placers in Siberia. Among the works published by Obruchev are textbooks on geology and geography that have become classics.

Formulate your attitude towards V. A. Obruchev as a science fiction writer. In the creation of science fiction novels, the author's desire not only for artistic, but also for scientific authenticity, in order to avoid inaccuracies that other writers made, played a certain role. If we assume that the land of Sannikov existed, then the events, people, nature described in the novel turn out to be scientifically quite reliable and accurate. One of the reasons for the success of the novels is the combination of V.A. Obruchev, scientist-researcher and artist.

12. Based on the knowledge gained in Western and Eastern Siberia:

1) compare the features of their geographical location;

2) explain how their geographical location affects nature;

3) establish how natural conditions affect the lives of people and the economy of these regions;

4) fill in the table.

Make a conclusion: are the natural conditions of Western or Eastern Siberia the most favorable for the life and economic activities of people? Based on the data in the table, we can conclude that the conditions of Western Siberia are more favorable for the life and economic activity of people.

13. Lake Baikal is a natural area with a very sharp environmental situation. The main sources of economic impact on the ecosystem of Lake Baikal are the industrial complexes of Ulan-Ude and Selenginsk (industrial effluents and air emissions), the reservoir of the Irkutsk hydroelectric power station (change in lake level), the Irkutsk-Cheremkhovo industrial hub (air emissions), logging enterprises (cutting down forests in the catchment basin), a marble quarry in Slyudyanka, etc.

On May 1, 1999, the Government of the Russian Federation adopted the law "On the Protection of Lake Baikal". Use the resources of the Internet to read this document. Write down the types of activities prohibited or restricted in the Baikal natural territory.

1. In the Baikal natural territory, activities are prohibited or restricted, the implementation of which has a negative impact on the unique ecological system of Lake Baikal:

Chemical pollution of Lake Baikal or its part, as well as its catchment area, associated with discharges and emissions harmful substances, the use of pesticides, agrochemicals, radioactive substances, the operation of transport, the disposal of production and consumption waste;

Physical change in the state of Lake Baikal or its part (change in water temperature regimes, fluctuations in water level indicators beyond the permissible values, change in runoff into Lake Baikal);

Biological pollution of Lake Baikal associated with the use, breeding or acclimatization of aquatic biological objects that are not characteristic of the ecological system of Lake Baikal, in Lake Baikal and water bodies that have a permanent or temporary connection with Lake Baikal.

In the central ecological zone, it is prohibited to place production and consumption wastes of I - III hazard classes.

2. On the Baikal natural territory, the construction of new economic facilities, the reconstruction of existing economic facilities without a positive conclusion of the state environmental review of the project documentation of such facilities is prohibited.

14. Norilsk is one of the ten most environmentally polluted cities in the world. The catastrophic state of the environment is caused by the activities of MMC Norilsk Nickel. It must be said that the sulfur content in the atmospheric precipitation of Norilsk has the highest rates not only in the Siberian region, but throughout Russia. According to the Russian Federal Service for Supervision of Natural Resources, the content of pollutants in the wastewater of the enterprise is tens and hundreds of times higher than the maximum permissible concentrations for heavy metals (zinc, iron, nickel, copper), as well as oil products, phosphates and nitrites discharged into the rivers of the region.

The complexity of solving the problem is determined by the specific composition of the raw materials, the position of Norilsk beyond the Arctic Circle, the lack of railway communication, as well as the impossibility of using sulfur dioxide utilization products - sulfuric acid and elemental sulfur - on site.

Experts believe that it is necessary to create the latest technologies to ensure a gradual reduction of sulfur dioxide emissions to safe levels.

Environmentalists believe that it is necessary to carry out a large-scale environmental program for the modernization of MMC enterprises.

Do you have your own view on solving this acute problem? Discuss this problem during the discussion.

15. What features are not typical for the nature of Eastern Siberia?

a) permafrost;

b) flat flat relief;

c) slight snow cover;

d) severe swamping of the territory.

16. Determine the landforms located in Eastern Siberia:

a) Vitim Plateau; c) the Central Siberian Plateau;

b) Yukagir Plateau; d) Dzhugdzhur ridge.

Answer: A, B

17. Determine the geographical objects that are not located on the territory of Eastern Siberia:

a) the Northern Dvina river; c) Sikhote-Alin;

b) the Angara river; d) the Putorana plateau.

Answer: A, B

18. Choose the correct statements:

a) the East Siberian region includes the Krasnoyarsk and Zabaikalsky territories, the Irkutsk region, the republics of Khakassia, Tyva and Buryatia;

b) there are no millionaire cities in Eastern Siberia;

c) the largest lake in the world by area is located in Eastern Siberia;

d) oil, gas and iron ore are the main minerals of Eastern Siberia.

19. Determine Largest cities Eastern Siberia:

a) Bratsk and Ust-Ilimsk; c) Krasnoyarsk and Irkutsk;

b) Krasnoyarsk and Norilsk; d) Dudinka and Ulan-Ude.

20. What are the numbers on the map?

1 - Bratsk, 2 - Abakan, 3 - Chita, 4 - Krasnoyarsk, 5 - Norilsk, 6 - Ulan-Ude, 7 - Lower Tunguska, 8 - Yenisei

21. Choose branches of specialization of Eastern Siberia:

a) electric power industry; c) textile industry;

b) non-ferrous metallurgy; d) pulp and paper industry.

Answer: A, B, D.

22. Choose the correct answers. Eastern Siberia is very important for Russia great importance, because here:

a) large centers of the automotive industry are concentrated;

b) the largest centers of the aluminum industry are located;

c) 1/3 of the country's forest resources are concentrated;

d) the largest hydroelectric power stations of the country are located.

Answer: B, G.

23. Match industrial production and its center.

1. Pulp and paper industry. A. Norilsk.

2. Woodworking. B. Sayanogorsk.

3. Copper production. V. Selenginsk.

4. Aluminum production. G. Lesosibirsk.

Answer: 1 - C, 2 - D, 3 - A, 4 - B

24. Choose from the list three cities that are major centers of aluminum production:

a) Novosibirsk; c) Rostov-on-Don; e) Krasnoyarsk;

b) Bratsk; d) Volgograd; e) Yekaterinburg.

Answer: B, D, D,

25. Choose the correct statements:

a) in Eastern Siberia, the centers of the aluminum industry are concentrated in the south of the region;

b) Eastern Siberia - the main metallurgical base of the country;

c) in Eastern Siberia there is the largest hydroelectric power station in Russia - Bratskaya;

d) the country's largest Sayano-Shushenskaya HPP was built on the Yenisei.

a) The North-East of Russia is characterized by sharp orographic contrasts: medium-altitude mountain systems predominate, along with them there are plateaus, highlands and lowlands. North-Eastern Siberia is a predominantly mountainous country; lowlands occupy a little more than 20% of its area. The most important orographic elements - the marginal mountain systems of the Verkhoyansk Range and the Kolyma Highlands - form a 4000 km long arc convex to the south. Inside it are located the chains of the Chersky ridge, elongated parallel to the Verkhoyansk system, the ridges Tas-Khayakhtakh, Tas-Kystabyt (Sarycheva), Momsky, and others.

The mountains of the Verkhoyansk system are separated from the Chersky ridge by a lowered strip of the Yansky, Elginsky and Oymyakonsky plateaus. The Nera plateau and the Upper Kolyma highlands are located in the east, and in the southeast the Sette-Daban ridge and the Yudomo-Maysky highlands adjoin the Verkhoyansk ridge.

The highest mountains are located in the south of the country. Their average height is 1500-2000 m, however, in the Verkhoyansk, Tas-Kystabyt, Suntar-Khayat and Chersky ridges, many peaks rise above 2300-2800 m, and the highest of them - Mount Pobeda in the Ulakhan-Chistai ridge - reaches 3003 m.

In the northern half of the country, the mountain ranges are lower and many of them stretch in a direction close to meridional. Along with low ridges (Kharaulakhsky, Selennyakhsky), there are flat ridge-like uplands (Polousny Ridge, Ulakhan-Sis) and plateaus (Alazeysky, Yukagirsky). A wide strip of the coast of the Laptev Sea and the East Siberian Sea is occupied by the Yana-Indigirskaya lowland, from which, along the valleys of the Indigirka, Alazeya and Kolyma, the intermountain Sredneindigirskaya (Abyiskaya) and Kolyma lowlands protrude far to the south.

Thus, the North-East of Siberia is a huge amphitheater, inclined towards the Arctic Ocean;

b) The main plan of the modern relief of North-Eastern Siberia was determined by neotectonic movements. In the development of the relief of the Northeast after the Mesozoic mountain building, two periods are distinguished: the formation of widespread leveling surfaces (peneplains); and the development of intense newest tectonic processes that caused splits, deformation and displacement of ancient alignment surfaces, volcanism, violent erosion processes. At this time, the formation of the main types of morphostructures takes place: folded-block areas of ancient median massifs (Alazeya and Yukagagir plateaus, Suntar-Khayata, etc.); mountains revived by the latest arch-block uplifts and depressions of the rift zone (Moma-Selennyakh depression); folded mid-mountains of Mesozoic structures (mountains Verkhoyansk, Sette-Daban, Anyui, etc., the Yanskoye and Elga plateaus, the Oymyakon highlands); stratal-accumulative, sloping plains, created mainly by subsidence (Yano-Indigirskaya and Kolyma lowlands); fold-block ridges and plateaus on the sedimentary-volcanic complex (the Anadyr plateau, the Kolyma highlands, the ridges - Yudomsky, Dzhugdzhur, etc.);

c) The territory of the current North-Eastern Siberia in the Paleozoic and the first half of the Mesozoic was a site of the Verkhoyansk-Chukotka geosynclinal marine basin. This is evidenced by the large thickness of the Paleozoic and Mesozoic deposits, in some places reaching 20-22 thousand m, and the intense manifestation tectonic movements who created the folded structures of the country in the second half of the Mesozoic. Especially typical are the deposits of the so-called Verkhoyansk complex, whose thickness reaches 12-15 thousand m. It includes Permian, Triassic and Jurassic sandstones and shale, usually intensively dislocated and broken through by young intrusions.

The most ancient structural elements are the Kolyma and Omolon median massifs. Their base is composed of Precambrian and Paleozoic deposits, and the Jurassic suites covering them, unlike other areas, consist of weakly dislocated carbonate rocks, occurring almost horizontally; effusives also play a prominent role.

The remaining tectonic elements of the country are of younger age, predominantly Upper Jurassic (in the west) and Cretaceous (in the east). These include the Verkhoyansk folded zone and the Sette-Dabansky anticlinorium, the Yana and Indigirsko-Kolyma synclinal zones, as well as the Tas-Khayakhtakhsky and Momsky anticlinoria. The extreme northeastern regions are part of the Anyui-Chukotka anticline, which is separated from the median massifs by the Oloy tectonic depression filled with volcanic and terrigenous Jurassic deposits;

d) The main types of relief of North-Eastern Siberia form several distinct geomorphological tiers. Key Features each of them are associated primarily with the hypsometric position, due to the nature and intensity of the latest tectonic movements. However, the location of the country in high latitudes and its harsh, sharply continental climate cause other than in more southern countries, altitudinal limits of the distribution of the corresponding types of mountainous relief. In addition, the processes of nivation, solifluction, and frost weathering are of greater importance in their formation. The forms of permafrost relief formation also play a significant role here, and fresh traces of Quaternary glaciation are characteristic even of plateaus and areas with low mountain relief.

In accordance with morphogenetic features, the following types of relief are distinguished within the country: accumulative plains, erosion-denudation plains, plateaus, low mountains, mid-mountain and high-mountain alpine relief.

Accumulative plains occupy areas of tectonic subsidence and accumulation of loose Quaternary deposits - alluvial, lacustrine, marine and glacial. They are characterized by slightly rugged topography and slight fluctuations in relative heights. Forms that owe their origin to permafrost processes, large ice content of loose deposits and the presence of thick underground ice are widespread here: thermokarst basins, permafrost heaving mounds, frost cracks and polygons, and high ice cliffs that are intensively collapsing on sea coasts. Accumulative plains occupy vast areas of the Yana-Indigirskaya, Sredneindigirskaya and Kolyma lowlands, some islands of the seas of the Arctic Ocean (Faddeevsky, Lyakhovsky, Bunge Land, etc.). Small areas of them are also found in depressions in the mountainous part of the country (Momo-Selennyakhskaya and Seimchanskaya hollows, Yanskoye and Elga plateaus).

Erosion-denudation plains are located at the foot of some northern ridges (Anyuisky, Momsky, Kharaulakhsky, Kulara), on the peripheral sections of the Polousny ridge, the Ulakhan-Sis ridge, the Alazeysky and Yukagirsky plateaus, as well as on Kotelny Island. The height of their surface usually does not exceed 200 m, but near the slopes of some ridges it reaches 400-500 m. Unlike accumulative plains, these plains are composed of bedrock different ages; the cover of loose sediments is usually thin. Therefore, rubble placers, sections of narrow valleys with rocky slopes, low hills prepared by denudation processes, as well as spots-medallions, solifluction terraces and other forms associated with the processes of permafrost relief formation are often found.

The plateau relief is most typically expressed in a wide strip separating the systems of the Verkhoyansk Range and the Chersky Range (Yanskoye, Elginskoye, Oymyakonskoye and Nerskoye plateaus). It is also characteristic of the Upper Kolyma Highlands, the Yukagir and Alazeya Plateaus, large areas of which are covered with Upper Mesozoic effusive rocks, which occur almost horizontally. However, most of the plateaus are composed of Mesozoic deposits folded into folds and represent denudation leveling surfaces, currently located at an altitude of 400 to 1200-1300 m. Upper Kolyma Highlands, where numerous granite batholiths appear in the form of high domed hills prepared by denudation. Many rivers in regions with a flat mountainous relief are mountainous in nature and flow in narrow rocky gorges.

The low mountains are occupied by areas subjected to uplifts of moderate amplitude (300-500 m) in the Quaternary. They are located mainly along the outskirts of high ridges and are dissected by a dense network of deep (up to 200-300 m) river valleys. The low mountains of North-Eastern Siberia are characterized by relief forms due to nival-solifluction and glacial processing, as well as an abundance of stony placers and rocky peaks.

The mid-mountain relief is especially characteristic of most massifs of the Verkhoyansk Range, the Yudomo-Maya Highlands, the Chersky Range, Tas-Khayakhtakh and Momsky. Significant areas are occupied by mid-mountain massifs also in the Kolyma Uplands and the Anyui Range. Modern medium-altitude mountains arose as a result of the latest uplifts of denudation plains of leveling surfaces, parts of which have been preserved here in places to this day. Then, in the Quaternary, the mountains were vigorously eroded by deep river valleys.

The height of the mid-mountain massifs is from 800-1000 to 2000-2200 m, and only at the bottom of deeply incised valleys the marks sometimes drop to 300-400 m. Relatively gentle relief forms prevail in the interfluve spaces, and fluctuations in relative heights usually do not exceed 200-300 m Forms created by Quaternary glaciers, as well as by permafrost and solifluction processes, are widespread everywhere. The development and preservation of these forms is facilitated by the harsh climate, since, unlike the more southern mountainous countries, many mid-mountain massifs of the Northeast are located above the upper limit of woody vegetation, in the mountain tundra. River valleys are quite diverse. Most often these are deep, sometimes canyon-like gorges (the depth of the Indigirka valley reaches, for example, 1500 m). However, the upper reaches of the valleys usually have a wide flat bottom and less high slopes.

The high-mountainous alpine relief is associated with areas of the most intense Quaternary uplifts, located at an altitude of more than 2000-2200 m. areas of the Verkhoyansk Range. Due to the fact that the most significant role in the formation of the Alpine relief was played by the activity of Quaternary and modern glaciers, it is characterized by deep dissection and large amplitudes of heights, the predominance of narrow rocky ridges, as well as cirques, cirques and other glacial landforms;

e) Among the minerals of this region, one can note numerous deposits of metals, in particular, tin, tungsten, gold, molybdenum, etc. These deposits are associated with Mesozoic-Cenozoic magmatism. Also in the region there are coal and brown coal basins (Zyryansky, Verkhoyansky).

The hydrographic network of Eastern Siberia belongs to the basin of the Arctic Ocean and is distributed over the private basins of the Kara, Laptev, East Siberian and Chukchi seas. By the nature of the relief, Eastern Siberia belongs to mountainous regions, and here mountains of medium height and vast plateaus predominate, while lowlands occupy only small spaces.

Between the Yenisei and Lena is the Siberian Plateau, dissected by erosion. Its height is on average 300-500 m above sea level; only in places among the plateau stand out higher elevations - the Putorana ridge (1500 m), the Vilyui mountains (1074 m) and the Yenisei ridge (1122 m). In the upper part of the Yenisei basin is the Sayano-Baikal fold country. This is the highest mountain region of the region, with heights up to 3480 m (the peak of Munku-Sardyk).

To the east of the lower reaches of the Lena stretches the Verkhoyansk-Kolyma mountainous country, characterized by sharp contrasts of lowland and mountain landscapes. Along the right bank of the Lena stretches a powerful arc of the Verkhoyansk ridge with heights up to 2000 m, further to the east rises the Chersky ridge - a mountain knot with a height of 2000-3000 m, the Tas-Khayakhtakh ridge, etc. Along with the mountain ranges, the Verkhoyansk-Kolyma mountain region includes Oymyakonskoye, Nerskoe and Yukagir plateaus. In the south, the border of the region is made up of the Yablonovy, Stanovoy and Duzhgdzhur ridges, whose heights reach 2500-3000 m. In the east, along the coast of the Sea of Okhotsk, the Kolyma ridge, or Gydan, stretches.

On the territory of Eastern Siberia, there are also low-lying plains, among which the Lena-Vilyui lowland stands out for its size, which is a grandiose synclinal trough. The extreme north of the region, along the coast of the marginal seas, is occupied by the Subpolar Lowland, the height of which does not exceed 100 m above sea level; lowlands are also located in the lower reaches of the Alazeya, Kolyma and Indigirka.

The subpolar lowland is occupied by tundra and forest tundra. Most of the territory of Eastern Siberia belongs to the taiga zone. The forest landscape is dominated by Daurian larch, which is most adapted to the harsh climate and the presence of permafrost; much less pine here. The forests of Eastern Siberia are slightly swamped.

The taiga zone on the territory of Eastern Siberia is dominant and extends far to the south; sections of the steppe and forest-steppe are interspersed in it in the form of spots (the Minusinsk depression, which has a steppe character, the steppes of Transbaikalia).

Geologically, the area is characterized by a shallow occurrence of bedrock crystalline rocks, which often come to the surface here. Large distribution, especially within the Central Siberian Plateau, are ancient igneous rocks - traps, which form characteristic vertical outcrops in the form of columnar units (locally - pillars) along the river valleys.

The rivers of Eastern Siberia are predominantly in the form of mountain streams; flowing through the lowlands, they acquire a flat character.

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federal state budgetary educational institution higher vocational education"National Mineral and Raw Materials University "Gorny"

Faculty of secondary vocational education

(College of Geodesy and Cartography)

TEST

by geography

Option number 8

Completed:

1st year student of PG-15z group

FULL NAME. Konyaev Artur Georgievich

Lecturer: Dashicheva A.V.

St. Petersburg-2015

TASK 1: Biogenic landforms. Relief-forming activity of animals and plants.

TASK 2: North-Eastern Siberia of Russia, physical and geographical characteristics

The relief is a set of forms of the earth's surface, different in shape, size, origin, age and history of development. The relief influences the formation of the climate, the nature and direction of the flow of rivers depend on it, the features of the distribution of flora and fauna are associated with it. The relief significantly affects the life and economic activity of a person.

The significance of organisms in the life of the Earth is great and varied. The processes of changing the surface of the Earth as a result of the activity of living organisms are called biogeomorphological, and the relief created with the participation of plants and animals is called biogenic. These are mainly nano-, micro- and mesoforms of relief.

A grandiose process, carried out largely due to organisms, is the formation of sediments (for example, limestones, caustobioliths and other rocks).

Plants and animals are also involved in a complex universal process - the weathering of rocks, both as a result of direct impact on rocks, and due to their metabolic products. Not without reason, sometimes, along with physical and chemical weathering, biological weathering is distinguished.

Plants and animals have a significant impact on different natural processes such as erosion. The destruction of vegetation on steep slopes, the trampling of plants by animals (the so-called "slaughter trails"), the loosening of soils by burrowing animals - all this increases erosion. This is especially dangerous on the mountain slopes, where distant pasture cattle breeding is carried out. There, due to excessive pasture load, various large-scale slope processes often come to life, the results of which are felt even in the foothills. Grassing of slopes (sowing meadow perennial long-rhizome grasses) holds soil together and reduces erosion.

Abundant aquatic vegetation in the rivers, as well as the inhabitants of water bodies, influence the channel processes. Beaver dams change the hydrological regime of rivers and geomorphological processes in the riverbed. Due to the damming of the rivers, swampy, hummocky floodplains are formed in the areas above the beaver dams.

Vegetation contributes to the overgrowth of lakes, filling them with organic matter. As a result, leveled hummocky surfaces of marshes appear on the site of lake basins. In the tundra, peat mounds are very characteristic.

Plants and animals are actively involved in the creation of some types of accumulative shores. In the equatorial-tropical latitudes, mangrove shores are formed, growing towards the sea due to the death of the plant mass. In temperate latitudes, along the shores of seas and lakes, reed shores similar to them appear.

On the coasts of the seas, shell beaches are created from animal shells with the participation of wave activity. Such accumulative landforms as coral structures are also widely known: coastal, barrier (for example, the Great Barrier Reef off the coast of Australia), ring atolls, which are numerous in the Pacific and Indian Oceans.

Burrowing animals also contribute to the formation of a biogenic relief. As a result of earth emissions, they create molehills, marmots, bobbins - mounds up to a meter high. Termite hills reach up to 4-5 m in height with a diameter of 15-20 m and create a kind of small-hilly relief in the Australian and African savannahs.

Animals and plants perform destructive work, which is often much more diverse and complex than the similar activity of various agents of inanimate nature (wind, water, etc.).

The accumulative activity of animals and plants causes a wide variety of positive landforms. You can, for example, point to marmot bumps, which are ejections of soil from holes. However, the largest positive landforms are formed due to the accumulation of plant residues in the form of peat. Ridges composed of peat are often found on the surface of raised bogs. Together with the depressions separating them (hollows), they create a kind of ridge-hollow surface of the marshes. The height of the ridges above the surface of the hollows ranges from 15 to 30 cm and rarely reaches 50-70 cm.

As a result of the vital activity of animals and plants, various forms of relief arise, which can be divided into the following main groups:

landforms due to their destructive activity;

landforms due to their accumulative activity.

The North-Eastern Siberia is located in the extreme north-east of Eurasia at the junction of three lithospheric plates- Eurasian, North American and Pacific, which determined the extremely complex terrain of the territory. In addition, over the course of a long geological history, cardinal rearrangements of tecto- and morphogenesis have repeatedly occurred here.

If we accept that the territory of North-Eastern Siberia corresponds to the late Mesozoic Verkhoyansk-Chukotka fold-cover region, then its boundaries are: in the west - the Lena valley and the lower reaches of the Aldan, from where, crossing the Dzhugdzhur, the border goes to the Sea of Okhotsk; in the southeast, the border runs along the lowland from the mouth of the Anadyr to the mouth of the Penzhina; in the north - the seas of the Arctic Ocean; in the south and east - the seas of the Pacific Ocean. Some geographers do not include the Pacific coast in North-Eastern Siberia, drawing the boundary along the watershed of the rivers of the basins of the Arctic and Pacific Oceans.

In the Precambrian and Paleozoic, median massifs appeared in this area in the form of individual microcontinents (Kolyma-Omolon and others), which during the Mesozoic folding were woven into the lace of folded mountains. At the end of the Mesozoic, the territory experienced peneplanization. At that time, there was an even warm climate with coniferous-broad-leaved forests, and North American flora penetrated here by land on the site of the Bering Strait. During the Alpine folding, the Mesozoic structures were split into separate blocks, some of which rose and others sank. The median massifs rose entirely, and where they split, lava came out. At the same time, the shelf of the Arctic Ocean sank and the relief of North-Eastern Siberia acquired the appearance of an amphitheater. Its highest steps run along the western, southern, and eastern borders of the territory (Verkhoyansk Range, Suntar-Khayata, and the Kolyma Highlands). A step below are numerous plateaus on the site of the median massifs (Yanskoye, Elginskoye, Yukagirskoye, etc.) and the Chersky Range with the highest point of North-Eastern Siberia - Mount Pobeda (3003 m). The lowest step is the marshy Yano-Indigirskaya and Kolyma lowlands.

Arctic desert zone.

Tundra zone.

Taiga zone.

The Arctic desert is part of the Arctic geographical zone, the basin of the Arctic Ocean. This is the northernmost of the natural zones, characterized by an arctic climate. The spaces are covered with glaciers, rubble and stone fragments.

It has low air temperatures in winter up to? 60 ° C, on average - 30 ° C in January and +3 ° C in July. It is formed not only due to the low temperatures of high latitudes, but also due to the reflection of heat (albedo) in the daytime from the snow and under the ice crust. The annual amount of atmospheric precipitation is up to 400 mm. In winter, the soil is saturated with layers of snow and barely thawed ice, the level of which is 75-300 mm. [Source not specified 76 days]

The climate in the Arctic is very harsh. Ice and snow cover lasts almost the whole year. In winter, there is a long polar night (at 75 ° N - 98 days; at 80 ° N - 127 days; in the region of the pole - half a year). This is a very harsh time of the year. The temperature drops to −40 °C and below, strong gale-force winds blow, snowstorms are frequent. In summer, there is round-the-clock lighting, but there is little heat, the soil does not have time to completely thaw. The air temperature is slightly above 0 °C. The sky is often overcast with gray clouds, it rains (often with snow), due to the strong evaporation of water from the surface of the ocean, thick fogs form.

Flora and fauna

The Arctic desert is practically devoid of vegetation: there are no shrubs, lichens and mosses do not form a continuous cover. The soils are thin, with patchy (island) distribution mainly only under vegetation, which consists mainly of sedges, some grasses, lichens and mosses. Extremely slow recovery of vegetation. The fauna is predominantly marine: walrus, seal, in summer there are bird colonies. Terrestrial fauna is poor: arctic fox, polar bear, lemming.

Tumndra is a type of natural zones lying beyond the northern limits of forest vegetation, an area with permafrost soil that is not flooded by sea or river waters. The tundra is located north of the taiga zone. By the nature of the surface of the tundra are swampy, peaty, rocky. The southern border of the tundra is taken as the beginning of the Arctic. From the north, the tundra is limited by the zone of arctic deserts. Sometimes the term "tundra" is applied to similar natural areas of Antarctica.

Tundra in Alaska in July

The tundra is characterized by a very harsh climate (the climate is subarctic), only those plants and animals that can endure cold and strong winds live here. In the tundra, large fauna is quite rare.

Winter in the tundra is extremely long. Since most of the tundra is located beyond the Arctic Circle, the tundra experiences a polar night in winter. The severity of winter depends on the continentality of the climate.

The tundra, as a rule, is deprived of climatic summer (or it comes for a very short time). The average temperature of the warmest month (July or August) in the tundra is 5-10 °C. With the advent of summer, all vegetation comes to life, as the polar day comes (or white nights in those areas of the tundra where the polar day does not occur).

May and September are the spring and autumn of the tundra. It is in May that the snow cover melts, and already in early October it usually sets again.

In winter, the average temperature is up to? 30 ° C

There can be 8-9 winter months in the tundra.

Animal and plant world

The vegetation of the tundra is primarily lichens and mosses; the angiosperms encountered are low grasses (especially from the Grass family), shrubs and shrubs (for example, some dwarf species of birch and willow, berry bushes, princess, blueberry).

Typical inhabitants of the Russian tundra are reindeer, foxes, bighorn sheep, wolves, lemmings and hare. There are few birds: Lapland plantain, white-winged plover, red-throated pipit, plover, snow bunting, snowy owl and ptarmigan.

Rivers and lakes are rich in fish (nelma, broad whitefish, omul, vendace and others).

The swampiness of the tundra allows the development of a large number of blood-sucking insects that are active in the summer. Due to the cold summer, there are practically no reptiles in the tundra: low temperatures limit the ability of cold-blooded animals to live.

Taigam is a biome characterized by the predominance of coniferous forests (boreal species of spruce, fir, larch, pine, including cedar).

Pinezhsky forest.

The taiga is characterized by the absence or weak development of undergrowth (since there is little light in the forest), as well as the monotony of the grass-shrub layer and moss cover (green mosses). Shrub species (juniper, honeysuckle, currant, etc.), dwarf shrubs (blueberries, lingonberries, etc.) and herbs (oxalis, wintergreen) are not numerous both in Eurasia and in North America.

In the north of Europe (Finland, Sweden, Norway, Russia) spruce forests predominate, in North America (Canada) - spruce forests with an admixture of Canadian larch. The taiga of the Urals is characterized by light coniferous forests of Scots pine. In Siberia and the Far East, sparse larch taiga dominates with an undergrowth of elfin cedar, Dahurian rhododendron, and more.

The fauna of the taiga is richer and more diverse than that of the tundra. Numerous and widespread: lynx, wolverine, chipmunk, sable, squirrel, etc. Of the ungulates, there are reindeer and red deer, elk, roe deer; hares, shrews, rodents are numerous: mice, voles, squirrels and flying squirrels. Of the birds, the following are common: capercaillie, common hazel grouse, nutcracker, crossbills, etc. The taiga of North America is typical of American species of the same genera as in Eurasia.

In the taiga forest, in comparison with the forest-tundra, the conditions for the life of animals are more favorable. There are more settled animals here. Nowhere in the world, except for the taiga, there are so many fur-bearing animals.

In winter, the vast majority of invertebrate species, all amphibians and reptiles, as well as some mammalian species, plunge into suspended animation and hibernation, and the activity of a number of other animals decreases.

Taiga types

According to the species composition, light coniferous (Scots pine, some American species of pine, Siberian and Dahurian larch) and more characteristic and widespread dark coniferous taiga (spruce, fir, stone pine, Korean cedar) are distinguished. Tree species can form pure (spruce, larch) and mixed (spruce-fir) forest stands.

The soil is usually sod-podzolic. Humidity is sufficient. 1-6% humus.

Evaporation 545 mm, precipitation 550 mm, average temperature in July 17°-20 °C, in winter the average temperature in January in the west? 6 °C, and in the east? 13 °C

A sharply continental climate operates on the territory of North-Eastern Siberia. Almost all of North-Eastern Siberia lies within the Arctic and Subarctic climatic zones. The temperature is on average below? 10 °.

North-Eastern Siberia can be divided into 3 climatic zones.

Hydrography

Northeastern Siberia is dissected by a network of many rivers flowing to the Laptev and East Siberian seas. The largest on them - Yana, Indigirka and Kolyma - flow almost in a meridional direction from south to north. Cutting through mountain ranges in narrow deep valleys and receiving numerous tributaries here, they, already in the form of high-water streams, go to the northern lowlands, where they acquire the character of flat rivers.

Most of the rivers are fed mainly by melting snow cover in early summer and summer rains. A certain role in the nutrition of rivers is played by groundwater, the melting of snow and glaciers in high mountains, as well as ice. More than 70% of the annual river flow falls on three calendar summer months.

The largest river in North-Eastern Siberia - Kolyma (basin area - 643 thousand km2, length - 2129 km) - begins in the Upper Kolyma Highlands. Somewhat below the mouth of the Korkodon River, the Kolyma enters the Kolyma Lowland; its valley widens sharply here, the fall and speed of the current decrease, and the river gradually acquires a flat appearance. Near Nizhnekolymsk, the width of the river reaches 2-3 km, and the average annual discharge is 3900 m3/sec (flow of about 123 km3 of water).

The sources of the second major river - the Indigirka (length - 1980 km, basin area - 360 thousand km2) - are located in the region of the Oymyakon Plateau. Crossing the Chersky Range, it flows in a deep and narrow valley with almost steep slopes; rapids are often found here in the channel of the Indigirka. Then the river enters the plain of the Sredneindigirskaya lowland, where it breaks into branches separated by sandy islands. Below the village of Chokurdakh, the delta begins, with an area of 7700 km2. Indigirka has a runoff of more than 57 km3 per year (an average annual flow is 1800 m3/sec).

The western regions of the country are drained by Yana (length - 1490 km2, basin area - 238 thousand km2). Its sources - the Dulgalakh and Sartang rivers - flow down from the northern slope of the Verkhoyansk Range. After their confluence within the Yan Plateau, the river flows in a wide valley with well-developed terraces. In the middle part of the current, where the Yana crosses the spurs of the mountain ranges, its valley narrows, and rapids appear in the channel. The lower reaches of the Yana are located on the territory of the coastal lowland; when it flows into the Laptev Sea, the river forms a large delta (about 5200 km2 in area).

Yana is characterized by long summer floods, which is due to the gradual melting of snow cover in the mountainous regions of its basin and the abundance of summer rains. The highest water levels are observed in July and August. The average annual discharge is 1000 m3/s, and the runoff per year is over 31 km3.

Most of the lakes of North-Eastern Siberia are located on the northern plains, in the basins of the Indigirka and Alazeya. Here there are places where the area of the lakes is not less than the area of the land separating them. The abundance of lakes, of which there are several tens of thousands, is due to the small ruggedness of the lowland relief, difficult runoff conditions, and the widespread permafrost. Most often, lakes occupy thermokarst basins or depressions in floodplains and on river islands. All of them are distinguished by their small size, flat banks, shallow depths (up to 4-7 m). For seven to eight months, the lakes are bound by a powerful ice cover; very many of them freeze to the bottom in the middle of winter.

On the territory of North-Eastern Siberia there is: gold, tin, polymetals, tungsten, mercury, molybdenum, antimony, cobalt, arsenic, coal.

Unlike other parts of Siberia, the amount of high-quality timber here is relatively small.

relief siberia russia

Literature

1. Lyubushkina S.G. General geography: Proc. allowance for university students enrolled in special. "Geography" / S.G. Lyubushkina, K.V. pashkang, A.V. Chernov; Ed. A.V. Chernov. - M. : Education, 2004. - 288 p.

2. N. A. Gvozdetsky and N. I. Mikhailov, Physical Geography of the USSR. Asian part. - 3rd ed., Rev. and additional Textbook for students geogr. fak. Univ. - M.: "Thought", 1978. 512 p.

3. Davydova M.I., Rakovskaya E.M. Physical geography of the USSR. - M.: Enlightenment, 1990.- 304 p.

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