Lesson 48. EASTERN SIBERIA AND NORTH-EASTERN SIBERIA. SPECIFICITY OF NATURE

Option 1

Option 2

1) Set the Match: Natural Frontier

a) the Arctic Ocean;

b) Kazakh Upland. Part of the border

south;

north;

west;

East.

The foundation of the West Siberian platform, in comparison with the East European platform, was formed:

a) earlier;

b) at the same time;

c) later.

The territory of Western Siberia has a general bias:

a) to the north;

b) to the south.

The lower-lying flat topography of Western Siberia is associated with:

a) with a greater depth of the foundation;

b) with the features of the new movements of the earth's crust.

The growing continental climate of Western Siberia is manifested in:

a) in a colder winter;

in colder winters and more rainfall

1) Set the correspondence:

Part of the border

a) west;

b) east.

Natural frontier

Ural Mountains;

Kazakh Upland;

Yenisei.

The foundation of the West Siberian platform compared to the East European:

a) younger;

b) the same age;

c) more ancient.

The relief of Western Siberia is:

a) the predominance of hills;

b) alternation of highlands and lowlands;

c) the predominance of lowlands.

The thickness of the sedimentary cover on the West Siberian platform in comparison with the East European:

a) less;

b) the same;

c) more.

The main reason for the increase in the degree of continentality of the climate in Western Siberia in comparison with the Russian Plain is: a) the impact of the Arctic Ocean;

reducing the influence of the Atlantic; c) weakening of the western transfer

1

6) Permafrost in Western Siberia, in comparison with the Russian Plain, has:

a) wider distribution;

b) less widespread.

Western Siberia has the following range of natural zones:

a) from arctic deserts to forest-steppes;

b) from tundra to steppes;

c) from forest tundras to semi-deserts.

The predominant type of soil in Western Siberia:

a) tundra-gley;

b) podzolized;

c) sod-podzolic

6) The boundary of the distribution of permafrost in Western Siberia is shifted in comparison with the East European Plain:

a) to the west;

b) to the north;

c) to the south.

The distribution of natural zones on the territory of Western Siberia is a manifestation of:

a) latitudinal zoning;

b) altitudinal zonality.

The main types of natural resources in Western Siberia are:

a) oil and gas;

b) oil, gas and forest resources;

c) oil, gas, forest and soil resources

Tasks: to form knowledge about the peculiarities of the geographical position of Eastern and North-Eastern Siberia as a factor that determines the natural features of this territory; to develop the skills of students to independently establish a connection between the geological structure and the relief and minerals; to systematize the knowledge of students about the reasons for the formation of a sharply continental climate in Eastern and North-Eastern Siberia; to consolidate the ability to independently determine quantitative climatic indicators for various regions of Siberia and to acquaint with the peculiarities of the climate; study the features of the regime and nature of the flow of rivers and their relationship with the relief and climate of Siberia.

1. Testing knowledge and skills on the topic "West Siberian Plain".

It is advisable to check the level of assimilation of knowledge and skills in a condensed form. Factual knowledge can be tested frontally in the form of a small test for options

Answers:

Option I - 1 - 1 c, 2a, 2 - c; 3 - a; 4 - b; 5 - a; 6 - a; 7 - b; 8 - c.

Option II - 1 - 1a, 2b; 2 - a; 3 - c; 4 - c; 5 - b, c; 6 - c; 7 - a; 8 - b.

II. Obtaining new knowledge.

The study of this topic is complicated by the lack of study time. When preparing for lessons, the teacher first of all selects the main thing, prepares assignments for students' independent work. The methods of organizing cognitive activity can be varied: solving cognitive problems, heuristic conversation, a seminar on the problems of rational use of natural conditions and resources, a game, a competition of characteristics of individual geographic objects, composing crosswords, small travel games.

The teacher distributes the study time at his own discretion. Traditionally, in the first lesson, natural components are considered, in the second, natural complexes are studied.

When studying the nature of Central and North-Eastern Siberia, it is important to draw the attention of students to the understanding of the features of nature, the manifestation of interconnections, the characteristic features and integrity of landscapes. For this, it is advisable to use a heuristic conversation with the practical and independent work of students with maps, a textbook, and visual aids.

1. Students characterize the geographical position of a large natural area "Eastern and Northeastern Siberia" independently, using a physical map of Russia and a map of large natural areas included in the atlas.

Questions and tasks:

1) What are the boundaries of Eastern and North-Eastern Siberia of the natural territory in the north, west, south and east.

2) Specify which landforms are part of Eastern and North-Eastern Siberia.

3) Describe the geographic location of this large natural area.

4) What is the peculiarity of its geographical position in comparison with the West Siberian Plain?

5) How does the Arctic Ocean affect the natural conditions of East and North-East Siberia?

6) How does the Atlantic Ocean affect the natural conditions of this part of Siberia?

7) Explain why the Pacific Ocean, relatively close to Eastern Siberia, has practically no effect on its natural conditions.

8) Make a general conclusion about how the geographical position of Eastern and North-Eastern Siberia affects the natural conditions of the territory.

Summarizing the students' answers, the teacher talks about the size of this natural territory and the reasons for close attention to the study of the natural conditions and resources of Eastern and North-Eastern Siberia at the present time.

1) On the tectonic map, establish on which geological structures Eastern and Northeastern Siberia is located.

2) What forms of relief are located in this area?

3) What is the originality of the surface structure?

When characterizing the relief, students pay attention to the fact that the territory of the region is much higher than neighboring Western Siberia. Uplands rise up to 500 m, plateaus - up to 1000 m, uplands - up to 1500 - 2000 m. The highest point is Pobeda Peak in the ridge. Chersky with a height of 3147 m. Thus, a conclusion is formed about the diversity of the relief of Eastern and North-Eastern Siberia.

When analyzing the tectonic map, students are convinced that the Siberian Platform lies at the base of the Central Siberian Plateau. How to explain the structure of the surface and differences in the relief on the plateau? If students have difficulties, then the teacher himself answers this question.

Teacher. The reason for the differences in the relief on the Central Siberian Plateau lies in the unevenness of the platform foundation. Where the foundation comes to the surface, the Anabar plateau was formed. Separate blocks of the basement are omitted, in the relief this is expressed by the lowlands - the North Siberian and Central Yakutsk. A feature of the region's relief is the presence of volcanic plateaus. In the Mesozoic, a huge amount of lava poured out through cracks in the platform, which, solidifying, formed continuous covers. A lot of lava solidified among sedimentary rocks. Subsequently, loose rocks were destroyed, and igneous ones remained, forming a stepped relief - traps. Another feature of the relief is the abundance of kurums. They are formed as a result of intense frost weathering.

4) Using the maps, determine which minerals are mined on the Central Siberian Plateau. Explain why both sedimentary and magmatic minerals are mined on the plateau.

5) What minerals are the mountains of Mesozoic folding and explain why there are many different minerals in these mountains?

The teacher only explains that deposits of ore minerals are associated with traps, and iron ore and diamonds are associated with kimberlite pipes.

Teacher. Interestingly, the discovery of diamonds on the territory of the Siberian Platform is an example of a brilliant confirmation of a scientific prediction. This forecast was made by V.S.Sobolev in 1937 based on a comparison of the geology of the Siberian and African platforms. The search for diamonds began in 1940, and in 1947 the first diamonds were found in placers, and in 1954 the first kimberlite pipes were found. A feature of the development of the mountains of North-Eastern Siberia is the formation of placer gold deposits. Placers are located in terraces, valleys and river beds. They were formed due to the erosion of granite igneous rocks. Gold is a common companion for tin, cobalt, arsenic and other ores.

3. The climatic features of Eastern and North-Eastern Siberia are studied using atlas maps. It is important that schoolchildren independently work through the factual material characterizing the features of the climate, and, relying on it, draw general conclusions about the typical features of the climate of this territory. The teacher organizes the work using the following tasks:

1) For the cities of Norilsk, Irkutsk and Oymyakon, determine the average temperatures in July, January and the annual temperature range; calculate the maximum annual temperature amplitude; calculate the moisture coefficient; determine the types of air masses.

2) On the basis of the obtained climatic data, draw a conclusion about the typical features of the climate of Eastern and North-Eastern Siberia.

Students write down the main features of the sharply continental climate in a notebook:

large fluctuations in daily, monthly and annual temperatures;

low amount of precipitation;

high volatility.

Oymyakon and Verkhoyansk are the cold poles of the northern hemisphere, where the average January temperature drops to -50 °, and the absolute minimum temperature is about -70 ° C.

3) What are the reasons that explain why in the vast territory of Eastern and Northeastern Siberia, stretching from north to south for 2000 km and from west to east for more than 3000 km, a sharply continental climate has formed with very cold winters, the warmest summers and a small amount of precipitation compared to other regions of Russia at the same latitudes.

The task should be completed in writing.

Climatic factors:

northern geographical position;

the influence of the Arctic;

remoteness from the Atlantic Ocean;

significant absolute heights of the terrain;

strong cooling of the mainland in winter, which contributes to the development of stable anticyclones.

4) Remember what kind of weather the winter anticyclones are characterized by and what atmospheric processes are observed in them.

Explanations of the teacher: The Siberian anticyclone is characterized by stable, very cold, clear, sunny, little cloudy, dry and calm weather in winter. The lowest air temperatures are observed in the interior regions of North-Eastern Siberia, in poorly ventilated intermontane basins, where cold air stagnates and is especially strongly cooled. It is in such places that Verkhoyansk and Oymyakon are located. These intermontane basins are characterized by winter temperature inversions in the lower air layer. During inversions, an increase in air temperature with a height of 2 degrees for every 100 m is observed. For this reason, it is less cold on the mountain slopes than in the basins, sometimes this difference is 15-20 °.

4. Characterizing the permafrost, the teacher draws the attention of students to the cause-and-effect relationship in nature.

In one case, permafrost is a consequence of climatic conditions, a sharp continental climate. It is almost ubiquitous throughout the region. The thickness of the permafrost layer in many places exceeds hundreds of meters (in the Vilyui basin - 600 m). In summer, the upper horizon of the frozen strata thaws in the north by 20-40 cm, and in the south by several meters.

In another case, permafrost is the cause that determines the development of other components and natural phenomena. It causes waterlogging of the plains, has a great influence on the regime of inland waters, cools the soil and thereby inhibits the soil-forming process. On permafrost, only plants with a superficial root system, such as larch, can grow.

5. In the final part of the lesson, in order to consolidate the students' skills to establish and characterize the connections of rivers with other components of nature, tasks of a partial search nature are proposed:

Explain why p. The Yenisei is the most abundant river in Russia, despite the fact that there is little rainfall in the basin.

Explain why there are many rapids and waterfalls on the Yenisei, Angara, Vilyue, but not on the Lena.

It is known that winters in Eastern Siberia are characterized by little snow, and in many places the snow is completely swept away. However, in spring, on the rivers of Siberia, there is a high rise in water, which reaches 10 m on the Lena, and even 20 - 25 m on the Lower Tunguska. Explain this natural phenomenon.

III. Summing up the lesson.

Homework: § 37, 38, draw the nomenclature on the contour map.

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

Occupies 1/4 of the area of ​​Russia;

Located in mid to high latitudes;

Removed from the Atlantic Ocean;

Restricted from the influence of the Pacific Ocean by a barrier of mountain ranges in the Far East

2. Complete the sentences.

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

2) Mountains predominate in the relief of Eastern Siberia; the Central Siberian Plateau is located in the center.

3) The climate is sharply continental.

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

5) The deepest lake in the world - Baikal is located here.

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

7) Branches of specialization of the region are non-ferrous metallurgy, mechanical engineering, timber industry, agriculture.

3. Why transport is especially important for Eastern Siberia? Give at least 3-4 reasons to support this.

The region's vast distances can only be covered 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 allow exploration of 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?" (pp. 182-183 of the textbook), reveal the significance of the Trans-Siberian and Baikal-Amur Mainlines for Siberia and the country.

The Trans-Siberian Railway, which is called the Great Siberian Route, connected the European part of Russia, the Urals, Siberia and the Far East. The main line played a significant role during the Russo-Japanese War for supplying the army, and 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, countries of Europe and America.

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

6. On the outline map (p. 78 Appendix):

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

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

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

9. Compare the 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 drop in the relief is 500-700 meters, but there are parts of the plateau where the absolute elevation 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 relief forms prevail.

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

1) What area in comparison with the area of ​​the district do they occupy? In Eastern Siberia, the steppe occupies intermountain hollows (Minusinskaya, Tuvinskaya).

2) What is their area in comparison with 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 Black Earth Region and in the European South.

11. Eastern Siberia was studied by Academician V. A. Obruchev. 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. Graduated from the Mining Institute in St. Petersburg in 1886. He was a professor at the Tomsk Technological Institute (1919-1921), the Taurida University in Simferopol (1918-1919) and the Moscow Mining Academy (1921-1929). Since 1930, Chairman of the Commission (Committee) for the Study of Permafrost, since 1939 Director of the Permafrost Institute of the USSR Academy of Sciences. In 1942-1946 academician-secretary of the Department of Geological and Geographical Sciences of the Academy of Sciences of the USSR.

2) Vladimir Obruchev is a famous 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 work of Obruchev is related to the solution of the following problems: the origin of loess in Central and Central Asia; glaciation and permafrost in Siberia; general issues of tectonics and tectonic structure of Siberia; proposed the term "neotectonics"; geology of Siberian gold deposits; 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 reaches of the Vitim, an oasis in Antarctica and other geographic objects, as well as the mineral obruchevit - a hydrated urano-yttrium pyrochlore variety.

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

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

2. Textbooks: "Field Geology" (v. 1-2, 1927), "Ore Deposits" (parts 1 - 2, 1928-29);

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

4. Science fiction novels: "Plutonium" (1915, published in 1924), "Sannikov's Land" (1924, published in 1926), "Desert Miners" (1928), "In the Wilds of Central Asia" (1951).

Make a conclusion: what is the contribution of the scientist to the development of geological and geographical science? V.A. Obruchev substantiated the concept of vertical movements of the earth's crust and their role in the modern relief of Siberia, proposed the term "neotectonics", compiled a summary of data on gold deposits, and a forecast of prospecting for gold placers in Siberia. Among the works published by Obruchev are textbooks on geology and geography, which 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 reliability played a role in order to avoid inaccuracies that other writers made. If we assume that Sannikov's land 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 in V.A. Obruchev scientist-researcher and artist.

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

1) compare the features of their geographic location;

2) explain how their geographic location affects nature;

3) establish how natural conditions affect the life 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 most favorable for the life and economic activity 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 acute ecological 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 pool), 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”. Using the resources of the Internet, read this document. Write down the types of activities that are prohibited or restricted in the Baikal natural territory.

1. On the Baikal natural territory, activities are prohibited or limited, in the implementation of which there is 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 of harmful substances, use of pesticides, agrochemicals, radioactive substances, operation of transport, disposal of production and consumption waste;

Physical change in the state of Lake Baikal or its part (change in temperature regimes of water, fluctuations in water level indicators outside the permissible values, change in flows 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 waste of I - III hazard classes.

2. On the Baikal natural territory, it is prohibited to build new economic facilities, reconstruction of existing economic facilities without a positive conclusion of the state environmental examination of the design documentation of such facilities.

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 the entire territory of Russia. According to Rosprirodnadzor of the Russian Federation, 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 location of Norilsk in the Arctic Circle, the lack of railway communication, as well as the inability to use sulfur dioxide utilization products on site - sulfuric acid and elemental sulfur.

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

Environmentalists believe that it is necessary to carry out a large-scale environmental program to modernize the enterprises of the mining and metallurgical complex.

Do you have your own view of the solution to this acute problem? Discuss this issue during the discussion.

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

a) Permafrost;

b) flat flat relief;

c) insignificant snow cover;

d) strong swampiness of the territory.

16. Identify the landforms located in Eastern Siberia:

a) Vitim plateau; c) Central Siberian plateau;

b) Yukagir plateau; d) Dzhugdzhur ridge.

Answer: A, B

17. Identify geographic objects that are not located in Eastern Siberia:

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

b) the Angara river; d) Putorana plateau.

Answer: A, B

18. Choose the correct statements:

a) the East Siberian region includes the Krasnoyarsk and Trans-Baikal 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 is located in Eastern Siberia;

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

19. Identify the largest cities in 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 - Nizhnyaya Tunguska, 8 - Yenisei

21. Select industries of specialization in 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, as 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 plants in the country are located.

Answer: B, D.

23. Establish a correspondence between 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. Select from the list three cities that are major centers of aluminum production:

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

b) Bratsk; d) Volgograd; f) 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) the largest hydroelectric power station in Russia is located in Eastern Siberia - Bratskaya;

d) the largest Sayano-Shushenskaya hydroelectric power station in the country was built on the Yenisei.

Questions and tasks

1. Compare the relief of Eastern and Western Siberia.

The modern relief of Western Siberia is due to geological development, tectonic structure and the influence of various exogenous relief-forming processes. The main orographic elements are closely dependent on the structural-tectonic plan of the plate, although the long-term Meso-Cenozoic subsidence and the accumulation of a thick stratum of loose deposits largely leveled the unevenness of the basement. The low amplitude of geotectonic movements is due to the low hypsometric position of the plain. The maximum amplitudes of uplifts reach 100 - 150 m in the peripheral parts of the plain, and in the center and in the north they are replaced by subsidence up to 100 - 150 m.However, within the plain, a number of lowlands and uplands are distinguished, commensurate in area with the lowlands and uplands of the Russian Plain.

Western Siberia has the shape of a stepped amphitheater, open to the north, to the coast of the Kara Sea. Within its limits, three high-altitude levels are clearly traced. Almost half of the territory has a height of less than 100 m. The second hypsometric level is located at heights of 100 - 150 m, the third - mainly in the range of 150 - 200 m with small areas up to 250 - 300 m.

The highest level is confined to the edge parts of the plain, to the Outer tectonic belt. It is represented by the Severo-Sosvinskaya, Verkhnetazovskaya and Lower Yeniseiskaya uplands, the Priobskoye plateau, the Turin, Ishimskaya, Kulundinskaya, Ketsko-Tymskaya plains.

Eastern Siberia is located on the ancient Siberian platform. And most of the region's territory is occupied by the Central Siberian Plateau, elevated above sea level from 500 to 1700 m. The foundation of this platform is the most ancient crystalline rocks, whose age reaches 4 million years. The next layer is sedimentary. It alternates with igneous rocks formed by volcanic eruptions. Therefore, the relief of Eastern Siberia is folded and stepped. It contains many mountain ranges, plateaus, terraces, deep river valleys.

2. Explain the climatic features of Eastern Siberia.

The formation of the climate of Eastern Siberia is affected by its territorial location and relief features. Far from the Atlantic Ocean, Eastern Siberia is characterized by pronounced continental climate features. This is manifested in exceptionally large seasonal differences in air temperature, low cloud cover, and small precipitation on a flat territory. In winter, the weather in Eastern Siberia is formed under the influence of a vast area of ​​high pressure - the Asian anticyclone. However, the position of the center of the anticyclone, the magnitude of the pressure in it and the area of ​​propagation change significantly during the cold period. This determines the variability of circulation, which is associated with day-to-day fluctuations in air temperature, which is especially typical for the south-west of Yakutia. Although cyclonic activity is weakened in winter, it significantly affects the weather: air masses change, precipitation falls, and snow cover forms. It is dominated by continental air, which cools in the surface layer, and in December - February it becomes colder in the lower layers of the Arctic. The average air temperature in January in the vast area of ​​Eastern Siberia varies from –26 in the southwest to –38, –42 ° in the Central Lowland. In valleys and depressions, the air temperature can drop to –60 °. However, against the background of a very low average monthly temperature with the removal of warmer continental air from Central Asia and China, relative warming is noted in the Baikal and Transbaikal regions, accompanied by an increase in temperature to –15 ° and higher. With prolonged removal of relatively warm air masses, the daytime air temperature in Eastern Siberia can be above 0 °. Summer in Eastern Siberia is warm: up to 30 - 40% of solar heat is spent on heating the air, and up to 50% in the south of Transbaikalia and the east of the Central Yakutsk lowland. Therefore, despite the influx of cold air from the Arctic seas, from the north of Western Siberia and from the Sea of ​​Okhotsk, average temperatures in July vary across the territory from north to south from 14 to 18 °. The highest temperatures in these regions occur when continental air is removed from China and Mongolia (35 - 38 °). In summer, the frequency of cyclones over Eastern Siberia is higher than in winter. They mainly come from the west, southwest and northwest. In the second half of the summer, there are outcrops of southern cyclones, which are associated with significant precipitation. The relief and features of atmospheric circulation distribute precipitation over the territory. The annual amount of precipitation varies within 130 - 1000 mm, and there is no well-expressed, as in the European territory of Russia and Western Siberia, a gradual decrease in precipitation to the south. The combination of heat and moisture contributes to the growth of forests in most of the territory of Eastern Siberia. However, the complex relief of this region violates the natural zoning.

3. Select from the text the features of the lake-river network of Eastern Siberia. What is their significance for the economic development of the region?

The basis of the river network is formed by the Yenisei and Lena, which are among the greatest rivers in the world. Both of them begin in the mountains of Southern Siberia and flow to the north in an almost meridional direction.

Both Yenisei and Lena are striking in their size and abundance of water; each of them collects water from a pool with an area of ​​more than 2 million square meters. km and has a length of more than 4 thousand km; annually in the seas of the Arctic Ocean, they carry over 1100 cubic meters. km of fresh, relatively warm water.

The interfluves of these rivers are drained by a dense network of their tributaries. The upper reaches of many large tributaries are often located close to each other, and this feature of the river network has long been used by the Russian population of Siberia.

There are a huge number of lakes in Eastern Siberia. The main one is the lake. Baikal. This is the deepest lake in the world - 1637 m. It contains the world's largest supply of fresh water (1/5).

Oz. Taimyr is located in the center of the Taimyr Peninsula, beyond the Arctic Circle, at the foot of the Byrranga plateau. This is the northernmost of the large lakes in the USSR. Its water surface area is 4650 km2. The lake is shallow. Its average depth is 2.8 m, maximum 26 m. The river flows into the lake. Upper Taimyr, and the river flows out. Lower Taimyr, flowing into the Taimyr Gulf of the Kara Sea. The average monthly surface water temperature in July is 5-7 °. The lake is free of ice for about 3 months.

It should be noted that some of the lakes of the alass-like depressions are significantly saline. The primary mineralization of these lakes, apparently, is associated with the mineral substances contained in the buried ice. Other lakes in the region. In the northwest of the region, in the lower reaches of the Yenisei, there is the Khantai group of glacial lakes. The largest of this group is the shallow lake. Pyasino with an area of ​​about 850 km2. Lama, Glubokoe, Khantayskoe, Vivi and others also belong to this group. An exceptional abundance of lakes is characteristic of the region of the Kolyma and Alazey lowlands. In the Vitim basin there are groups of Eravninsky and Arakhleysky lakes. A significant number of lakes are located in the Baikal region and in Transbaikalia, as well as in the upper part of the Yenisei basin, in the so-called Minusinsk depression.

4. Name the features of the natural zones of Eastern Siberia, using the text of the paragraph and maps of the atlas.

On the northern plains and in mountainous regions, tundra and forest-tundra dominate, and in the Far North, on the oceanic coast of Taimyr and on the Arctic islands (Severnaya Zemlya), arctic deserts.

Most of Eastern Siberia is covered with light-coniferous larch forests, the border of which goes far enough in the north - up to 70 s. sh. In the Krasnoyarsk Territory, larch forests occupy half of the entire taiga.

In the Angara basin, large areas are also occupied by pine forests, and in the Western Baikal region - by dark coniferous spruce-cedar forests. Only in the southern regions of the region in the hollows (Minusinskaya, Kuznetskaya) are areas of steppes and forest-steppes found. The region has huge reserves of wood raw materials. The total timber stock is almost 40% of the all-Russian fund. However, the main forest tracts are located in underdeveloped territory, where there is almost no logging.

Fur-bearing animals are an important wealth of the region: sable, squirrel and arctic fox, the main object of hunting for the indigenous population of this region. Agricultural land is concentrated mainly in the southern part of the region, in the steppe and forest-steppe areas and along the river banks in the taiga zone. The harsh climatic conditions and the inaccessibility of many regions, the rare population, despite the innumerable natural resources, are a constraining factor in the economic development of Eastern Siberia.

General characteristics of North-Eastern Siberia

To the east of the lower reaches of the Lena River lies a vast territory, bounded in the east by the mountains of the Pacific watershed. This physical and geographical country was named North-Eastern Siberia. Including the islands of the Arctic Ocean, North-Eastern Siberia covers an area of ​​more than $ 1.5 million square kilometers. Within its borders is the eastern part of Yakutia and the western part of the Magadan region. Northeastern Siberia is located in high latitudes and is washed by the waters of the Arctic Ocean and its seas.

Cape Svyatoy Nos is the northernmost point. The southern regions are in the Mai river basin. To the north of the Arctic Circle, almost half of the country's territory is located, which is characterized by a varied and contrasting relief. There are mountain ranges, plateaus, flat lowlands along the valleys of large rivers. Northeastern Siberia belongs to the Verkhoyansk-Chukotka Mesozoic folding, when the main folding processes took place. The modern relief was formed as a result of the latest tectonic movements.

Finished works on a similar topic

Climatic conditions of North-East Siberia are severe, January frosts reach - $ 60, - $ 68 degrees. Summer temperature + $ 30 $, + $ 36 $ degrees. The range of temperatures in some places is $ 100 - $ 105 degrees, little precipitation, about $ 100 - $ 150 mm. Permafrost binds the ground to a depth of several hundred meters. On flat territories, zoning is well expressed in the distribution of soils and vegetation cover - on the islands there is a zone of arctic deserts, mainland tundra and uniform swampy larch woodlands. Altitude zoning is typical for mountainous regions.

Remark 1

Pathfinders I. Rebrov, I. Erastov, M. Stadukhin provided the first information about the nature of North-Eastern Siberia. This was the middle of the $ 17th century. The northern islands were studied by A.A. Bunge and E.V. Toll, but the information was far from complete. Only in the $ 30 years of the expedition S.V. Obruchev changed ideas about the peculiarities of this physical and geographical country.

Despite the diversity of the topography, North-Eastern Siberia is mainly a mountainous country, lowlands occupy $ 20% of the area. Here are the mountain systems of the marginal ridges of the Verkhoyansk, Chersky, Kolyma Uplands. In the south of Northeastern Siberia there are the highest mountains, the average height of which reaches $ 1500 - $ 2000 m. Many peaks of the Verkhoyansk ridge and the Chersky ridge rise above $ 2300 - $ 2800 m. The top is located in the Ulakhan-Chistai ridge - this is Mount Pobeda, whose height is $ 3147 m.

Geological structure of the North-East of Siberia

In the Paleozoic era and at the beginning of the Mesozoic era, the territory of North-Eastern Siberia belonged to the Verkhoyansk-Chukotka geosynclinal sea basin. The main evidence of this is the powerful Paleozoic-Mesozoic deposits, reaching in places $ 20 - $ 22 thousand meters and strong tectonic movements that created folded structures in the second half of the Mesozoic. The most ancient structural elements are the middle massifs Kolymsky and Omolonsky. Younger age - in the west the Upper Jurassic, and in the east Cretaceous - have the rest of the tectonic elements.

These elements include:

1. Verkhoyansk fold zone and Sette - Daban aticlinorium;
2. Yanskaya and Indigirsko-Kolymskaya synclinal zones;
3. Tas-Khayakhtakh and Momsky anticlinoria.

By the end of the Cretaceous, northeastern Siberia was a territory elevated above neighboring regions. The warm climate of this time, and the denudation processes of the mountain ranges leveled the relief and formed flat surfaces of the alignment. The modern mountainous relief was formed under the influence of tectonic uplifts in the Neogene and Quaternary periods. The amplitude of these uplifts reached $ 1000 - $ 2000 $ m. Especially high ridges rose in those areas where the uplifts were most intense. Cenozoic subsidence is occupied by lowlands and intermontane basins with strata of loose deposits.

From about the middle of the Quaternary period, glaciation began, and large valley glaciers appeared on the mountain ranges that continued to rise. The embryonic nature of glaciation was, according to D.M. Kolosov, on the plains, firn fields formed here. The formation of permafrost begins in the second half of the Quaternary period in the archipelago of the New Siberian Islands and on the coastal lowlands. The thickness of permafrost and subsurface ice reaches $ 50 - $ 60 m in the cliffs of the Arctic Ocean.

Remark 2

Thus, the glaciation of the plains of North-Eastern Siberia was passive. A significant part of the glaciers were inactive formations that carried a little loose material. The exaration effect of these glaciers on the relief had little effect.

Mountain-valley glaciation is more pronounced; on the outskirts of mountain ranges, there are well-preserved forms of glacial gouging - kars, trough valleys. Valley mid-Quaternary glaciers reached a length of $ 200 - $ 300 km. The mountains of North-Eastern Siberia, according to most experts, experienced three independent glaciations in the Middle Quaternary and Upper Quaternary.

These include:

1. Tobychanskoe glaciation;
2. Elga glaciation;
3. Bohapcha glaciation.

The first glaciation led to the emergence of Siberian conifers, including the Daurian larch. In the second interglacial epoch, mountain taiga was predominant. It is typical for the southern regions of Yakutia at the present time. The last glaciation had almost no effect on the species composition of modern vegetation. The northern limit of the forest at that time, according to A.P. Vaskovsky, was noticeably displaced to the south.

Relief of the North-East of Siberia

The relief of North-Eastern Siberia forms several well-defined geomorphological layers. Each tier is associated with a hypsometric position, which was determined by the nature and intensity of the latest tectonic movements. The position in high latitudes and the sharp continentality of the climate determine other altitudinal limits of the distribution of the corresponding types of mountainous relief. In its formation, the processes of nivation, solifluction, and frost weathering are of greater importance.

Within North-Eastern Siberia, in accordance with morphogenetic features, there are:

1. Accumulative Plains;
2. Erosion-denudation plains;
3. Highlands;
4. Low mountains;
5. Mid-mountain and low-mountain alpine relief.

Some areas of tectonic subsidence occupy accumulative plains characterized by a slightly rugged relief and small fluctuations in relative altitude. Such forms are spread, which owe their formation to permafrost processes, large ice content of loose sediments and powerful underground ice.

Among them are:

1. Thermokarst basins;
2. Frozen heaving mounds;
3. Frost cracks and polygons;
4. High ice cliffs on the sea coasts.

The accumulative plains include the Yano-Indigirskaya, Sredne-Indigirskaya, and Kolyma lowlands.

At the foot of a number of ridges - Anyuisky, Momsky, Kharaulakh, Kular - formed erosion-denudation plains... The surface of the plains has a height of no more than $ 200 $ m, but it can reach $ 400 - $ 500 $ m on the slopes of a number of ridges. Loose deposits are thin here and they are composed mainly of bedrocks of different ages. As a result, one can find here rubble placers, narrow valleys with rocky slopes, low hills, medallion spots, solifluction terraces.

Between the Verkhoyansk ridge and the Chersky ridge, there is a pronounced plateau relief- Yanskoe, Elginskoe, Oymyakonskoe, Nerskoe plateaus. Most of the plateaus are composed of Mesozoic deposits. Their modern height is from $ 400 to $ 1300 m.

Those areas that underwent uplifts of moderate amplitude in the Quaternary are occupied by low mountains, $ 300 - $ 500 m. They occupy a marginal position and are dissected by a dense network of deep river valleys. Typical landforms for them are the abundance of stony placers and rocky peaks.

Mid-mountain relief is mainly typical for most of the massifs of the Verkhoyansk ridge system. Yudomo-Maisky highlands, Chersky ridge, Tas-Khayakhtakh, Momsky. The Kolyma Upland and Anyui Ridge also have mid-mountain ranges. Their height is from $ 800 $ - $ 2200 m. The mid-mountain massifs of North-Eastern Siberia are located in a strip of mountain tundra, above the upper limit of woody vegetation.

High alpine relief... These are the ridges of the highest mountain ranges - Suntar-Khayata, Ulakhan-Chistay, Tas-Khayakhtakh, etc. They are associated with the regions of the most intense uplifts of the Quaternary period. Height over $ 2000 - $ 2200 m. In the formation of the alpine relief, a significant role belongs to the activity of Quaternary and modern glaciers, therefore, large amplitudes of heights, deep dissection, narrow rocky ridges, kars, circuses and other glacial landforms will be characteristic.

EASTERN SIBERIA, a natural region located mainly in Russia. It is located in Siberia, between the Yenisei River valley and the watershed ridges along the Pacific coast, stretching south of the Chukotka Peninsula. In the north it is washed by the Kara, Laptev and East Siberian seas.

Naturally complex Eastern Siberia includes the following physical and geographical countries: Central Siberia, partly the Altai-Sayan country (with the Eastern Sayan mountain system), North-Eastern Siberia, the Baikal region and Transbaikalia. The relief is dominated by low and medium mountains. In the west, the largest in Russia Central Siberian Plateau stands out. In the east, complex mountain systems (ridges Verkhoyanskiy, Cherskiy, etc.) are combined with plateaus (Yanskoye, Elginskoye, Alazey, Yukagirskoye, etc.) and uplands (Oymyakonskoye, Kolymskoye, etc.). In the south, there are also a number of vast uplands (Stanovoe, Aldanskoe, Patomskoe, etc.). Alpine relief forms with modern glaciation (Orulgan, Momsky, Sunta-Khayata, etc.) are developed in some high-mountain ranges. In the north, there are a number of large lowlands - the North Siberian, Yano-Indigirskaya, Kolymskaya, etc.

The tectonic structures of Eastern Siberia are represented by the Siberian platform and its folded framing: in the north - the Early Mesozoic structure of Taimyr; in the west - the system of the Yenisei Ridge of Baikal age; in the southeast - the structures of the Salairian-Caledonian-Hercynian Altai-Sayan folded region. In the south, the Baikal-Mongol-Okhotsk region is located, in which the time of the main folding in various mountain systems varies from the Late Proterozoic to the Late Mesozoic. To the east of the Siberian platform is the Late Mesozoic Verkhoyansk-Chukotka fold area. The southern part of Eastern Siberia in the Cenozoic was covered by mountain building. The eastern regions are experiencing active uplift. One of the largest continental rift systems in the world, the Baikal rift system, is located in the south of Eastern Siberia. High seismicity is typical for the southern (basin of Lake Baikal with adjacent territories, Eastern Sayan) and eastern (Verkhoyansk and Chersky ridges) regions. Strong destructive earthquakes occurred in 1862 (in the delta of the Selenga River), 1927 (Bulunskys in the Verkhoyansk ridge), 1950 (in the Eastern Sayan), 1957 (Muiskoe in the Transbaikalia), 1959 (Srednebaikalskoe), 1971 (Artykskoe in the Chersky ridge). Known deposits of oil and natural combustible gas, coal, iron ores, gold, uranium, platinum, tin, copper, nickel, cobalt, antimony, mercury, niobium, rare earth elements, as well as diamonds, phlogopite, muscovite, asbestos, stone and potassium salts, etc.

The climate of Eastern Siberia is sharply continental. In the regions of Oymyakon and Verkhoyansk, there is a cold pole of Eurasia (the absolute minimum is -68 ° С). Permafrost is widespread, reaching a maximum thickness of 1500 m (the Markha River basin). Thermokarst lakes are numerous in the north and northeast. The largest rivers of Russia flow through the territory of Eastern Siberia: Lena, Yenisei, Kolyma, Indigirka; there is a unique lake Baikal. The northern lowlands of Eastern Siberia are occupied by tundras: arctic, moss-lichen and shrub on peat-cryozems. To the south, a narrow strip of forest-tundra, without a sharp transition, is replaced by the northern subzone of taiga larch forests on coarse-humus cryozems. Larch forests are widespread in the middle and southern subzones of the taiga on cryoturbated pale-pale soils and coarse-humus light soils. In the south of the Central Siberian Plateau, there are forest-steppe islands. The zonal distribution of soil and vegetation cover is disturbed in the Byrranga mountains and on the Putorana plateau, as well as in high areas of the plateaus. The structure of altitudinal zonation in the northeastern part of Eastern Siberia differs sharply from the southern part, where it is more diverse.

The active development of natural resources, the development of large industrial centers has led to the emergence of areas with a tense ecological situation (Norilsk, Kemerovo, Irkutsk, etc.), which is aggravated by the weak ability of the natural environment of this region to self-purify. A number of nature reserves have been created (Taimyr, Barguzinsky, Central Siberian, Vitimsky, etc.) and national parks (Pribaikalsky, Zabaikalsky, Tunkinsky, etc.). The World Heritage List includes: Lake Baikal, Ubsunur Basin (most of it in Mongolia).

Lit .: Plains and mountains of Siberia. M., 1975; A.V. Antipova Geography of Russia. M., 2001.