Low Africa. Forms and relief of Africa

10 Features of the relief of Africa

1.Features of physical geographical location.

2. The main stages of geological history.

Mediterranean region

Gondwana region

3. Characteristics of morphological regions.

1. Africa is the second largest continent, area = 29.2 million km (with islands 30.3 million km) or 1/5 of the land area of ​​the globe. The most important for the formation of the features of the nature of the continent is its symmetrical position relative to the equator. 2/3 of the mainland is located in the northern hemisphere and 1/3 in the southern. Therefore, it is correct to say that the extreme northern and southern point equidistant from the equator.

Northern Cape - El Abyad (Ben Secca) -37 20N

Southern Cape Igolny –34 52 S

Africa is washed by the Indian and Atlantic Oceans (the Mediterranean and Red Seas).

An important feature of the geographical position of Africa is its proximity to the Eurasian continent. The narrow (120 km) Isthmus of Suez connects it with Asia. Africa is separated from Europe by the Strait of Gibraltar, up to 14 km wide.

The shores of the mainland are slightly indented, usually without well-protected natural bays. The slight horizontal division of Africa is due to the fact that about 22% of its territory is more than 100 km away from the sea.

Off the coast of Africa there are islands: in the east - Madagascar, Comoros, Mascarene, Amirante, Seychelles, Pemba, Mafia, Zanzibar, Socotra; in the west - Madeira, Canaries, Cape Verde, Sao Tome, Principe, Fernando Po, and Ascension, St. Helena, Tristan da Cunha lying at a great distance.

2. At the base of most of the mainland lies the ancient African platform, composed of crystalline, metamorphosed and igneous rocks of the Precambrian, whose age in some areas reaches 3 billion years. The basement rocks are overlain by a sedimentary cover that occupies 2/3 of the continent. In the Paleozoic and during most of the Mesozoic, the platform, apparently, was part of the hypothetical Gondwana mainland. From the northwest and from the south, the Precambrian basement of the mainland is framed by Hercynian folded structures. In the south they make up the Cape Mountains, in the northwest the interior zones of the Atlas Mountains. The northern chains of these mountains (Er-Rif, Tell-Atlas) are the only alpine folded structures on the mainland.

S-ancient platform 96%

S-Paleozoic folded zones 3%

S- Cenozoic-Mesozoic zones 1%

The African platform is complicated by syneclises and anteclises. The largest syneclises are Karru, Kalahari, Congo, Chad (Mali-Nigerian), Aravan-Taudeni, and Libyan-Egyptian. The largest shields and uplifts of the Archean-Proterozoic basement are the Ahaggar, Regibat, Leono-Liberian, Nubian-Arabian, Central African, Madagarskar massifs. The most significant protrusions of the ancient foundation are located along the eastern margin of the mainland. Here is also the world's largest East African fault system, stretching for 6500 km from the Gulf of Aqaba through the Red Sea, the Ethiopian Highlands, the East African Plateau and the lower reaches of the Zambezi River.

Taking into account the peculiarities and differences in the geological history of the mainland, two regions are distinguished - the northern Mediterranean and the southern Gondwana. The border between them runs from the Gulf of Guinea to Aden.

The Mediterranean region in the Paleozoic and Meso-Cenozoic occupied a predominantly low hypsometric position and repeatedly experienced transgression. In the east, in the deep regions of the Sahara and Sudan, a predominantly continental regime was preserved in the Paleozoic and Mesozoic. During this period, there is an accumulation of Nubian sandstones. The Hercynian tectonic movements, which manifested themselves mainly in the Atlas sector, were followed by a general uplift of the region and the accumulation of continental Triassic sequences. In the Jurassic, the sea covered only the territory of Egypt and Sudan. Starting from the Cretaceous, large blocks of the platform are submerged in the Gulf of Guinea area. The sea floods its coast and penetrates into Sudan along the ancient grabens of the Niger and Benue rivers to the southern slopes of the Ahaggar massif. In the Upper Cretaceous most of The Mediterranean region represents the marine basin. Since the beginning of the Cenozoic era, the Mediterranean region has been experiencing a general uplift, the sea has receded, and in the Holocene the territory of the region is in continental conditions. Under the influence of folding movements in the Tethys geosyncline, the Regibat and Tuareg, as well as the Nubian-Arabian shields were uplifted, which led to the junction of the Saharan and Arabian parts of the platform.

At the same time, modern outlines of large syneclises—Senegalese, Chad, White Nile, and Aravan-Taudenny—filled with Neogene-Quaternary continental sediments, took shape.

The Gondwana region of the platform has been an uplifted area since the Paleozoic. Sedimentary strata accumulated here only in intracontinental syneclises - the Karoo, Kalahari and Congo basins and on the coasts, under conditions of marginal transgressions. Since the beginning of the Paleozoic era, a geosyncline extends along the southern margin of the platform, in the shallow zone of which the formations of the Cape system were deposited, crumpled into folds in the early Triassic.

(Hercynian orogeny). When the Cape Mountains were uplifted, a foredeep was laid in front of them, which subsequently developed into the Karru syneclise.

Since the end of the Paleozoic era, the uplift of the Gondwana region has been intensifying. In the Permian, along the eastern margin of the region, splits occurred, along which the Madagascar block separated, and the graben of the Mozambique Strait was laid. In the Triassic, the sea set foot on the eastern coast of Africa and spread north to the Somali Peninsula by the Cretaceous, and in the south, the transgression engulfed the destroyed Cape Mountains. Particularly sharp amplitudes were in the southeastern sector in connection with which in the Dragon Mountains in the Jurassic, an outpouring of basaltic lava occurred along deep faults.

The Paleogene-Neogene and Quaternary tectonics of the Gondwana region was manifested by several phases of strong uplifts of the marginal zones of the platform, including the Cape Mountains, which led to the rejuvenation of the mountains. However, the main tectonic events are associated with the formation of the fault system of the Ethiopian Plateau and East Africa. Along the fault line, sections of the earth's crust were lowered to a great depth, as a result of which complex systems of grabens arose.

The fault system in its modern form began to form from the Oligocene simultaneously with the growth of large uplifts and mountain building in eastern Africa and Arabia. Movements along the faults led to a powerful outbreak of volcanic activity, which reached its maximum in the Neogene and continues at the present time; all active volcanoes in Africa are located in this zone.

3. Africa is a high continent. The average height of the mainland is 750m (second only to Antarctica and Eurasia).

The highest altitude belongs to the city of Kilimanjaro (5895m). Africa is the only continent where the main peaks do not belong to the zones of folded structures. The “lowest” place on the mainland is the Assal depression (-150m) and Kattara (-133m).

The predominance of a leveled relief on the mainland is due to its platform structure. According to the prevailing heights, Africa is divided into 2 subcontinents: Low and High Africa. Low Africa occupies about 2/3 of the mainland, covering its northern and western parts: here the heights are mainly below 1000 m. High Africa occupies the southern and eastern parts of the mainland, where heights of more than 1000 m prevail.

Features of morphosculptures. The relief of the mainland in the modern period is changing under the influence of exogenous processes, which are different in climatic zones. In tropical latitudes, physical weathering dominates, chemically unaltered coarse detrital rubble material is formed, fragments are demolished under the influence of gravity, sand is transported by wind and aeolian accumulation occurs. Weathering crust of insignificant thickness. Its composition retains many weakly altered primary minerals, even such unstable ones as mica and feldspars. Subequatorial latitudes are characterized by an alternation of erosion processes (during wet seasons) and physical weathering (during dry seasons). During wet seasons, most of the carbonates and sulfates are carried out of the soil, forming calcareous and gypsum nodules; there is a massive hydrolysis of silicates and aluminosilicates with the formation of clay minerals and iron hydroxides. The latter lose water during dry seasons and turn into water-poor hydrohematites or hematites. Deeply decomposed lateritic weathering crusts, or laterites, arise.

In equatorial latitudes, the weathering crust is intensively washed out by atmospheric precipitation and all soluble weathering products are carried out by water. Primary silicates and aluminosilicates are converted into minerals of the kaolinite group, which do not contain alkali and alkaline earth metals. A thick (up to 50-100) kaolin weathering crust is formed. In many parts of Africa where iron or salt crusts are exposed or shallow, the surface is resistant to erosion.

Cryogenic -----

Glacial ------

Fluvial 57.6%

Arid 42.4%

In accordance with the morphotectonic history of the African continent, the most important morphotectonic differences have formed in its relief, on the basis of which several structural and morphological regions are distinguished on the territory of Africa.

Atlas mountain country. The northern coastal part of this country is an alpine folded structure. In the structure of the southern part of the mountainous country, Paleozoic formations (Moroccan Meseta), which experienced intensive Hercynian tectogenesis, play a significant role. To the east (the zone of the High Plateaus, including the Oranskaya Meseta), weakly deformed shallow marine deposits of the Cretaceous and Paleogene occur. In the zone of the High and Saharan Atlas, the thickness of the Mesozoic increases. In the south, the Atlas is separated by a large fault (South Atlas) from the African Platform. Another fault runs along the coast mediterranean sea. The Atlas mountain country is distinguished by a variety of morphosculptures:

Traces of ancient glaciation (kars, troughs, moraines, etc.)

The interior regions are occupied by denudation and accumulative plains, cuesta ridges, and remnant plateaus.

In areas where calcareous rocks are distributed, karst is widely developed.

in relief Saharan table plateau plains below 500m predominate. Large uplifts only in the Central Sahara, the Ahaggar highlands (Tahat, 3003m) and Tibesti (Emi-Kusi, 3415m) bearing traces of active Neogene and Anthropogenic volcanism (lava fields, deposits of geysers), are dissected by deep canyons and dry channels of ancient and modern watercourses. The plateaus of Iforas (up to 728m), Air (up to 1900m), Ennedi (up to 1310m) adjoin Ahaggar and Tibesti from the south. This area is characterized by numerous drainless depressions: Shott-Melgir (-26m), Siva, Kattara (-133m), etc.

The region of plains and low table plateaus of Sudan. The prevailing heights are 200-500m, above the flat surface of which rise mountains-remnants, indicating the level of denudation of this territory. A typical table plateau is Kordofan. Important elements of the relief are river valleys, channels of temporary streams, lake basins. AT modern era The formation of the relief is due to the processes of weathering and erosional activity.

Upper Guinean uplifts. It includes the Sierra Leone Upland, the Cameroon Plateau with the Cameroon Volcano (4070m), which are confined to the anteclise of the African Platform and represent low mountain rises (1000-1500m).

5.Congo depression occupies a huge syneclise of the same name, composed mainly of continental deposits. From all sides it is surrounded by ledges of the crystalline basement (Lunda-Katanga plateau, Azande), which break off in steps to the Congo syneclise.

6.Abyssinian Highlands. The northern part is peneplain on crystalline rocks with insular mountains, the southern part is a stepped plateau, divided by deep canyon-like valleys into separate massifs. The highest height is reached by the Symen Mountains (Ras Dashan, 4623m). In the southeast, the highlands break off in steep steps to a deep fault depression that separates the Somali plateau. Transverse lava thresholds divide the depression into several basins, at the bottom of which there are traces of active tectonic activity: fumaroles, hot springs.

7. East African highlands. It is characterized by a complex combination of various landforms that are closely related genetically. The heavily terraced coastal lowlands experienced uplift at the start of the Quaternary. East Africa is characterized by massive blocky uplifts (Rwenzori Massif, Livingston Mountains). On the western outskirts there is a chain of deep lakes lying in graben-like depressions. To the east of Lake Victoria rise the most significant rises in East Africa - the volcano Kenya (5199m), Kilimanjaro (5895m), Meru (4565m). In addition, the relief of the highlands is characterized by the presence of giant craters (Ngorongoro up to 20 m in diameter).

8.South African region occupies the Kalahari and Karoo syneclises. The area is elevated to a considerable height and is distinguished by the simplicity of the relief structure. Above the sandy plains of the Kalahari basin, marginal plateaus and mountains (the Matabele, Weld, Dragon Mountains, etc.) rise in steps. The Nam and Dammar uplifts stand out. To the south they continue into the denudation Great Scarp that separates the Upper Karoo Plateau from the Cape Mountains.

cape mountains belong to a rare type of revived mountains with an inherited folded structure, clearly expressed in the modern relief. The Cape Mountains are made up of several parallel ranges. Wed height 1500m, the highest -2326m. The mountains are low, flat-topped, formed during the era of the Hercynian orogeny. They were subjected to a long leveling, and at the end of the Neogene they were uplifted.

dragon mountains composed of light sandstones of the Karoo system, overlain by dark-colored basalts, causing the flat tops of the Drakensberg Mountains.

Africa is the second largest continent of the Earth after Eurasia. Its area is 30.3 million km2. Among other continents, Africa occupies a special geographical position. Almost in the middle it is crossed by the equator and is located mainly between the Northern and Southern tropics. In the west passes the initial (zero) meridian. Thus, Africa is located, on the one hand, in the Northern and Southern Hemispheres, on the other - in the Western and Eastern Hemispheres. This gigantic land area belongs to the group of so-called southern continents, which have many common features. From north to south, Africa stretches for 8,000 km. The widest part of the mainland is in the Northern Hemisphere.

The shores of Africa are washed by the waters of the Atlantic and Indian oceans. On the west coast, the Atlantic Ocean forms a large Gulf of Guinea. Along West Bank a narrow (up to 100 km) continental shelf stretched.

In the east, the only large peninsula of Somalia protrudes into the Indian Ocean. The islands off the coast of Africa are few in number. The largest of them - Madagascar is separated from the continent in the east by the Mozambique Channel. In tropical latitudes, the western coast of the mainland is washed by the cold Canary and Benguela currents, and the eastern coast by the warm Mozambique current. The African continent is closely connected with Eurasia. They are separated by the Straits of Gibraltar and Bab el-Mandeb, the Mediterranean and Red Seas, and the Suez Canal. Africa and Eurasia are a single land mass in the Eastern Hemisphere, separated from other continents by vast ocean expanses.

The geographical position of Africa determines the high air temperatures in most of it and contributes to the vivid manifestation of geographical zonality on its territory.

Geographical explorations of Africa

(Using the thematic map of the atlas, determine which areas of Africa were most explored in the 19th century.) Research in Africa has been uneven. The southern regions of Africa, in comparison with the northern ones, became known to Europeans much later. African exploration was associated with the search sea ​​route to India, and from the 15th century. with the development of the slave trade. In search of a way to India, B. Dias was the first to go around Africa from the south. Later (1497-1499) Vasco da Gama, rounding the Cape of Good Hope and exploring the eastern coast of Africa, reached the shores of India. To expand their possessions, England and France organize a number of expeditions. The vast hinterland became known to Europeans only from the middle of the 19th century.

In the nineteenth century An important contribution to the study of South and Central Africa was made by the English naturalist David Livingston. He studied animals and vegetable world, natural features of travel areas. D. Livingston was the first to describe the geology and relief of South Africa, explored the Kalahari Desert, a number of lakes, including Nyasa, the Zambezi River. Having lived in Africa for thirty years, D. Livingston proved himself to be a humane and noble researcher, single-handedly fought against the slave trade.

The Anglo-American expedition of Henry Stanley explored lakes Victoria and Tanganyika and established their outlines, discovered mountain range Rwenzori, recognized the Kagera River as the main tributary of Lake Victoria. G. Stanley corrected the mistake of D. Livingston, who had previously accepted the source of the river. Congo for the source of the river. Nile.

Among Russian researchers, a special place is occupied by V. V. Junker, who collected interesting information about the nature of Central and East Africa at the end of the 19th century. A doctor by education and a geographer by vocation, VV Juncker traveled the continent for ten years at his own expense. He described the flora and fauna of tropical forests and savannahs, carried out meteorological observations, and for the first time compiled a map of the watershed area of ​​the great African rivers - the Nile, the Congo and the Niger. N. I. Vavilov, studying the centers of origin of cultivated plants, in the 20s. 20th century organized scientific expeditions for the study of the vegetation of the Mediterranean (Algeria, Tunisia, Morocco, Ethiopia). In the second half of the XVI century. Nikolai Radziwill (Orphan) visited Africa.

The structure of the earth's crust and the relief of Africa

At the base of most of the mainland lies the ancient African-Arabian platform. Under the influence of tectonic movements and external processes over a long geological time, the surface of the mainland was leveled: sections of the platform were raised and lowered, the raised sections were destroyed, and the depressions were filled with sediments. This is what determined the modern forms and features of the relief, the presence of minerals on the continent. The relief of Africa is represented mainly by elevated plains, and the eastern part - by plateaus and highlands.

The sedimentary cover over the platform basement is more developed in North Africa (Sahara Plate). Deflections of the crystalline basement lie at the base of the Congo, Kalahari, and Karoo depressions. The highlands of Ahaggar, Tibesti, the North Guinean and South Guinean uplifts, and the East African Plateau are confined to uplifts and outcrops of the crystalline basement - shields.

A significant part of the area of ​​the continent is occupied by the East African Plateau and the Ethiopian Highlands. They were formed under the influence of internal processes (lifting and spreading), which contributed to the fact that individual parts of the platform rose. The movements were accompanied by breaks in the earth's crust with the formation of horsts and grabens, and volcanic eruptions. Thus, large lava sheets formed on the Ethiopian Highlands. As a result of tectonic processes in the eastern part of the mainland, linearly elongated tectonic structures were formed - rifts that stretched along the Red Sea through the Ethiopian highlands to the river. Zambezi. Separate cracks gradually expanded and filled with water, forming deep and elongated lakes: Tanganyika, Nyasa, Rudolf, Edward, Albert. This area is called the East African Rift Zone.

Here is the highest peak in Africa - Mount Kilimanjaro (5895 m) and the lowest place on the mainland - Lake Assal (157 m below sea level).

In the north and south of the mainland, folded areas, formed in different geological periods, adjoin the African-Arabian platform. These are mountainous regions: in the north - the young Atlas folded mountains, which are part of the Alpine-Himalayan folded belt, and in the south - the more ancient dilapidated Cape Mountains. In the era of the last mountain building, the outlying parts of the mainland were uplifted, as a result of which blocky flat-topped Dragon Mountains were formed. Lowlands (Senegalese, Mozambique, etc.) are found along the coasts of Africa and in river valleys.

Minerals of Africa

Africa is rich in a variety of minerals. Their placement is determined by the structure of the earth's crust and the geological history of its development. The sedimentary cover of the Sahara Plate and the coastal lowlands of the Gulf of Guinea are rich in oil reserves (Algeria, Libya, Egypt, Nigeria). Rich ore deposits have been discovered on crystalline shields. To the west of the East African Plateau stretches the famous African copper belt. Iron ore deposits have been explored in northern Africa, and manganese deposits have been explored in the basins of the Congo and Orange rivers.

Gold reserves are located in the south of the continent - in South Africa. The largest deposits of iron ores, chromites, gold, diamonds and uranium ores. In places of ancient volcanism in South and East Africa, diamond deposits were formed ( kimberlite pipes). In South Africa, sedimentary strata contain large reserves of coal. Oil and phosphorite deposits have been discovered in the Atlas folded region.

Africa almost in the middle is crossed by the equator and most of it is located between the tropics. This explains its hot climate. A notable contribution to the study of Africa was made by Russian researchers - V. V. Junker (meteorological observations and the study of flora and fauna), N. I. Vavilov (study of vegetation).

1. Why does the study of the features of the mainland begin with determining its geographical position?

The study of geographic location should begin with the definition of geographic location. It is the geographical location that determines many characteristics of the mainland: the amount of heat and the set of climatic zones, the prevailing winds, the amount of precipitation, coastal currents.

2. What is the main feature of Africa is determined by its geographical position?

Due to its geographical position, Africa is the hottest continent.

3. Fill in the gaps in the sentences using textbook text and a map of Africa.

The area of ​​mainland Africa is 30.3 million km2. The population of the mainland is more than 900 million people. Africa is the hottest continent on Earth. Africa is located in subtropical, tropical, subequatorial and equatorial climatic zones. The shores of the mainland are poorly dissected. Most large island- Madagascar is of continental origin, it is located about 400 km east of Africa.

5. Remember from the geography course of grades 5-6 what types of plains are distinguished by height. Using a physical map, chart Views of the Plains of Africa. Give examples of each type of plain.

In terms of height, the plains are low (up to 200 m), elevated (200-500 m), highlands (above 500 m).

6. Determine what types of plains are shown on the African relief profile in Figure 66 in the textbook.

The profile shows elevated plains and plateaus.

9. Here are four climate charts. Determine which climate zone they characterize.

1 - tropical;

2 - subtropical;

3 - equatorial;

4 - subequatorial.

10. What natural zone and what geographical object are we talking about in the following passage?

Desert natural zone, Sahara.

13. Apply to contour map and sign the warm and cold currents off the coast of Africa.

Cold - Canary, Benguela, Samal current.

Warm - Guinea, Angolan, for Cape Agulhas, Mozambique for.

14. Using the map of climatic zones in the atlas, determine in which main and transitional climatic zones Africa is located.

The main belts are equatorial and tropical.

Transitional belts - subequatorial, subtropical.

15. Determine on the map which basins of the oceans the rivers belong to:

Nile - Atlantic Ocean;

Congo - Atlantic Ocean;

Zambezi - Indian Ocean;

Niger - Atlantic Ocean;

Limpopo - Indian Ocean;

Senegal - Atlantic Ocean.

18. How would you dress if you were at the mouth of the Congo River? Justify the answer.

The mouth of the Congo River is located in subequatorial belt in the natural zone of variable-humid forests. In conditions of high temperature and humidity, wear light is better clothes from natural materials. However, for security, it needs to be closed.

19. Imagine that the island of Madagascar will shift south by 300. How will the climate and natural areas on the island change?

If the island moves 300 south, it will be within the temperate and subantarctic climatic zones. Temperatures will be much lower. Rainforests will be replaced by mixed and coniferous, in the extreme south - by tundra.

20. One of the major problems on the African continent is deforestation. Continue the chain of changes in the natural complex that will occur as a result of the destruction of forests in order to harvest valuable tree species for export.

Determine which part of Africa is experiencing the most intensive deforestation. What can you suggest to solve the problem?

Intensive deforestation is taking place in the Congo Basin. Considering that forests are climatic and hydrological regulators, deforestation in the equatorial regions of the Earth can lead to radical climate change. In this regard, there is a need to protect not just some forest areas or typical forests, but the entire forest fund of the planet, all logging must certainly be accompanied by reforestation.

21. What letter on the map (Fig. 5) indicates Cape Agulhas?

BUT); AT); FROM); D)

22. What letter on the map (Fig. 6) indicates the Atlas Mountains?

BUT); AT); FROM); D)

23. Almost the entire continent experiences the action of winds:

1) monsoons;

2) trade winds;

3) Western

2) trade winds

24. in figure 7, the numbers indicate:

1) the Congo River;

2) Atlas mountains;

3) the Nile River;

4) Dragon mountains;

5) Lake Victoria;

6) Ethiopian highlands;

7) Lake Tanganyika

8) Lake Chad.

25. Dry riverbeds in Africa are called:

3) meanders

26. Specify the excess:

3) Victoria;

4) Orange

3) Victoria.

27. The Zambezi River is full-flowing:

3) autumn;

28. The population of Africa is:

1) 900 million people;

2) 500 million people;

3) 1.5 billion people

1) 900 million people

1) in the Nile Delta;

2) in the Sahara;

3) on the coast of the Gulf of Guinea

1) in the Nile Delta

30. What letter on the map (Fig. 8) indicates Angola?

BUT); AT); FROM); D)

31. What letter on the map (Fig. 9) is Nigeria?

BUT); AT); FROM); D)

32. Match:

Peoples Where they live

1) pygmies; A) South Africa

2) drills; B) the Congo basin;

3) Berbers; B) Kalahari

4) Bushmen; D) Sugar

1-B; 2-A; 3-G; 4-B.

33. Most of Africa is occupied by a natural zone:

1) savannas and light forests;

2) deserts and semi-deserts;

3) humid equatorial forests;

4) forest-steppes and steppes

1) savannas and woodlands

34. What letter on the map (Fig. 10) indicates the zone of savannas and light forests?

BUT); AT); FROM); D)

35. Choose the only false statement:

1. 40% of the area of ​​Africa is occupied by savannahs.

2. The Benguela Current contributed most to the formation of the Namib Desert.

4. There is no temperate climate zone in Africa.

3. The extreme northern point of Africa is Cape Piai.

36. Which of the statements is correct?

A) Baobab is a characteristic tree of the African savannas.

b) The Strait of Gibraltar separates Africa from the Arabian Peninsula.

1) only A is true;

2) only B is true;

3) both are true;

4) both are wrong

Africa is a part of the world with an area of ​​\u200b\u200bwith islands of 30.3 million km 2, this is the second place after Eurasia, 6% of the entire surface of our planet and 20% of the land.

Geographical position

Africa is located in the Northern and Eastern Hemispheres (most), a small part in the Southern and Western. Like all big pieces ancient mainland Gondwana has a massive outline, large peninsulas and deep bays are absent. The length of the continent from north to south is 8 thousand km, from west to east - 7.5 thousand km. In the north it is washed by the waters of the Mediterranean Sea, in the northeast by the Red Sea, in the southeast by the Indian Ocean, in the west by the Atlantic Ocean. Africa is separated from Asia by the Suez Canal, from Europe by the Strait of Gibraltar.

Main geographical features

Africa lies on an ancient platform, which determines its flat surface, which in some places is dissected by deep river valleys. On the coast of the mainland there are few lowlands, the northwest is the location of the Atlas Mountains, Northern part, almost completely occupied by the Sahara desert - the Ahaggar and Tibetsi highlands, the east - the Ethiopian highlands, the southeast - the East African plateau, the extreme south - the Cape and Drakensberg mountains. Nai highest point Africa - Kilimanjaro volcano (5895 m, Masai plateau), the lowest - 157 meters below sea level in Lake Assal. Along the Red Sea, in the Ethiopian Highlands and to the mouth of the Zambezi River, the world's largest fault in the earth's crust stretches, which is characterized by frequent seismic activity.

Rivers flow through Africa: Congo (Central Africa), Niger ( West Africa), Limpopo, Orange, Zambezi (South Africa), as well as one of the most full-flowing and longest rivers in the world - the Nile (6852 km), flowing from south to north (its sources are on the East African plateau, and it flows into delta in the Mediterranean). The rivers are high-water only in the equatorial zone, due to the large amount of precipitation there, most of them are characterized by a high flow rate, have many rapids and waterfalls. In lithospheric faults filled with water, lakes formed - Nyasa, Tanganyika, the largest freshwater lake in Africa and the second largest after Lake Superior ( North America) - Victoria (its area is 68.8 thousand km 2, length 337 km, max depth - 83 m), the largest saline drainless lake - Chad (its area is 1.35 thousand km 2, located on the southern outskirts of the world's greatest desert Sahara).

Due to Africa's location between two tropical belts, it is characterized by high total solar radiation, which gives the right to call Africa the hottest continent on Earth (the highest temperature on our planet was recorded in 1922 in El Azizia (Libya) - +58 C 0 in the shade).

On the territory of Africa, such natural zones are distinguished as evergreen equatorial forests (the coast of the Gulf of Guinea, the Congo depression), in the north and south turning into mixed deciduous-evergreen forests, then there is a natural zone of savannahs and light forests, extending to Sudan, East and South Africa, to Sevre and southern Africa savannas are replaced by semi-deserts and deserts (Sahara, Kalahari, Namib). In the southeastern part of Africa there is a small zone of mixed coniferous-deciduous forests, on the slopes of the Atlas Mountains - a zone of hard-leaved evergreen forests and shrubs. natural areas mountains and plateaus are subject to the laws of altitudinal zonation.

African countries

The territory of Africa is divided among 62 countries, 54 - independent, sovereign states, 10 dependent territories belonging to Spain, Portugal, Great Britain and France, the rest - unrecognized, self-proclaimed states - Galmudug, Puntland, Somaliland, Saharan Arab Democratic Republic(SADR). For a long time, the countries of Asia were foreign colonies of various European states and only by the middle of the last century gained independence. Africa is divided into five regions based on geographic location: North, Central, West, East and South Africa.

List of African countries

Nature

Mountains and plains of Africa

Most of the African continent is a plain. Available mountain systems, uplands and plateaus. They are presented:

• the Atlas Mountains in the northwestern part of the continent;
• the Tibesti and Ahaggar uplands in the Sahara desert;
• Ethiopian highlands in the eastern part of the mainland;
• Dragon Mountains in the south.

The highest point in the country is Mount Kilimanjaro, with a height of 5,895 m, belonging to the East African Plateau in the southeastern part of the mainland ...

Deserts and savannas

The largest desert zone of the African continent is located in the northern part. This is the Sahara Desert. On the southwestern side of the continent is another smaller desert, the Namib, and from it, inland to the east, is the Kalahari Desert.

The territory of the savanna occupies the main part of Central Africa. In terms of area, it is much larger than the northern and southern parts of the mainland. The territory is characterized by the presence of pastures typical for savannahs, low shrubs and trees. The height of grassy vegetation varies depending on the amount of precipitation. It can be almost desert savannas or tall grasses, with grass cover from 1 to 5 m in height...

Rivers

On the territory of the African continent is the longest river in the world - the Nile. Its direction of flow is from south to north.

In the list of major water systems of the mainland, Limpopo, Zambezi and the Orange River, as well as the Congo, which flows through the territory of Central Africa.

On the Zambezi River is the famous Victoria Falls, 120 meters high and 1,800 meters wide...

lakes

The list of large lakes of the African continent includes Lake Victoria, which is the second largest freshwater reservoir in the world. Its depth reaches 80 m, and its area is 68,000 square kilometers. Two more large lakes of the continent: Tanganyika and Nyasa. They are located in the faults of the lithospheric plates.

There is Lake Chad in Africa, which is one of the world's largest endorheic relict lakes that have no connection with the oceans ...

Seas and oceans

The African continent is washed by the waters of two oceans at once: the Indian and the Atlantic. Also off its coast are the Red and Mediterranean Seas. From the side Atlantic Ocean in the southwestern part of the water form the deep Gulf of Guinea.

Despite the location of the African continent, coastal waters are cool. This is influenced by the cold currents of the Atlantic Ocean: the Canary in the north and the Bengal in the southwest. From the side indian ocean currents are warm. The largest are Mozambique, in northern waters, and Igolnoye - in the southern ...

Forests of Africa

Forests from the entire territory of the African continent make up a little more than a quarter. Here are subtropical forests growing on the slopes of the Atlas Mountains and the valleys of the ridge. Here you can find holm oak, pistachio, strawberry tree, etc. Coniferous plants grow high in the mountains, represented by Aleppo pine, Atlas cedar, juniper and other types of trees.

Closer to the coast there are forests of cork oak, in the tropical region evergreen equatorial plants are common, for example, mahogany, sandalwood, ebony, etc...

Nature, plants and animals of Africa

The vegetation of the equatorial forests is diverse, there are about 1000 species of various tree species: ficus, ceiba, wine tree, olive palm, wine palm, banana palm, tree ferns, sandalwood, mahogany, rubber trees, Liberian coffee tree, etc. . It is home to many species of animals, rodents, birds and insects living right on the trees. On earth live: bush pigs, leopards, African deer - a relative of the okapi giraffe, large apes - gorillas ...

40% of the territory of Africa is occupied by savannahs, which are huge steppe areas covered with forbs, low, thorny shrubs, milkweed, and stand-alone trees (tree-like acacias, baobabs).

Here there is the largest accumulation of such large animals as: rhinoceros, giraffe, elephant, hippopotamus, zebra, buffalo, hyena, lion, leopard, cheetah, jackal, crocodile, hyena dog. The most numerous animals of the savannah are such herbivores as: bubal (family of antelopes), giraffe, impala or black-fifth antelope, various types of gazelles (Thomson, Grant), blue wildebeest, and in some places there are rare jumping antelopes - springboks.

The vegetation of deserts and semi-deserts is characterized by poverty and unpretentiousness, these are small thorny shrubs, separately growing bunches of herbs. The oases grow a unique date palm Erg Chebbi, as well as plants resistant to drought conditions and salt formation. In the Namib Desert, unique velvichia and nara plants grow, the fruits of which feed on porcupines, elephants and other animals of the desert.

Of the animals, various species of antelopes and gazelles live here, adapted to the hot climate and capable of traveling great distances in search of food, many species of rodents, snakes, and turtles. Lizards. Among mammals: spotted hyena, common jackal, maned ram, Cape hare, Ethiopian hedgehog, dorcas gazelle, saber-horned antelope, Anubis baboon, wild Nubian donkey, cheetah, jackal, fox, mouflon, there are permanently living and migratory birds.

Climatic conditions

Seasons, weather and climate of African countries

The central part of Africa, through which the equator line passes, is in a low pressure area and receives sufficient moisture, the territories north and south of the equator are in the subequatorial climatic zone, this is a zone of seasonal (monsoonal) moisture and arid desert climate. The extreme north and south are in the subtropical climate zone, the south receives precipitation brought by air masses from the Indian Ocean, the Kalahari Desert is located here, the north - minimal amount precipitation, due to the formation of a high pressure area and the peculiarities of the movement of the trade winds, the largest desert in the world is the Sahara, where the amount of precipitation is minimal, in some areas it does not fall at all ...

Resources

African Natural Resources

In terms of water resources, Africa is considered one of the least prosperous continents in the world. The average annual volume of water is only enough to meet primary needs, but this does not apply to all regions.

Land resources are represented by large areas with fertile lands. Only 20% of all possible land is cultivated. The reason for this is the lack of the proper volume of water, soil erosion, etc.

The forests of Africa are a source of timber, including species of valuable varieties. The countries in which they grow, the raw materials are exported. Resources are misused and ecosystems are slowly being destroyed.

In the bowels of Africa there are deposits of minerals. Among those sent for export: gold, diamonds, uranium, phosphorus, manganese ores. There are significant reserves of oil and natural gas.

Energy-intensive resources are widely represented on the continent, but they are not used due to the lack of proper investments...

Among the developed industrial sectors of the countries of the African continent, one can note:

• the mining industry that exports minerals and fuels;
• the oil refining industry, distributed mainly in South Africa and North Africa;
• chemical industry specializing in the production mineral fertilizers;
• as well as the metallurgical and engineering industries.

main products Agriculture are cocoa beans, coffee, corn, rice and wheat. In the tropical regions of Africa, oil palm is grown.

Fishing is poorly developed and accounts for only 1-2% of the total volume of agriculture. The indicators of animal husbandry are also not high, and the reason for this is the infection of livestock with tsetse flies ...

culture

The peoples of Africa: culture and traditions

On the territory 62 African countries There are about 8,000 peoples and ethnic groups, which in total is about 1.1 billion people. Africa is considered the cradle and ancestral home of human civilization, it was here that the remains of ancient primates (hominids) were found, which, according to scientists, are considered the ancestors of people.

Most of the peoples in Africa may number from several thousand people to several hundred living in one or two villages. 90% of the population are representatives of 120 peoples, their number is more than 1 million people, 2/3 of them are peoples with more than 5 million people, 1/3 - peoples with more than 10 million people (this is 50% of the total population of Africa) - Arabs , Hausa, Fulbe, Yoruba, Igbo, Amhara, Oromo, Rwanda, Malagasy, Zulu...

There are two historical and ethnographic provinces: North African (the predominance of the Indo-European race) and Tropical-African (the majority of the population is the Negroid race), it is divided into such areas as:

• West Africa. The peoples speaking the Mande languages ​​(Susu, Maninka, Mende, Wai), Chadic (Hausa), Nilo-Saharan (Songhai, Kanuri, Tubu, Zagawa, Mawa, etc.), Niger-Congo languages ​​(Yoruba, Igbo, Bini, nupe, gbari, igala and idoma, ibibio, efik, kambari, birom and jukun, etc.);
• Equatorial Africa. Inhabited by Buanto-speaking peoples: Duala, Fang, Bubi (Fernandese), Mpongwe, Teke, Mboshi, Ngala, Komo, Mongo, Tetela, Cuba, Kongo, Ambundu, Ovimbundu, Chokwe, Luena, Tonga, Pygmies, etc.;
• South Africa. Rebellious-speaking peoples, and speaking Khoisan languages: Bushmen and Hottentots;
• East Africa. Bantu, Nilotic and Sudanese groups of peoples;
• North East Africa. Peoples speaking Ethio-Semitic (Amhara, Tigre, Tigra.), Cushitic (Oromo, Somalis, Sidamo, Agau, Afar, Konso, etc.) and Omotian languages ​​(Ometo, Gimirra, etc.);
• Madagascar. Malagasy and Creoles.

In the North African province, the main peoples are considered to be Arabs and Berbers, belonging to the South Caucasian minor race, mainly practicing Sunni Islam. There is also an ethno-religious group of Copts, who are direct descendants of the Ancient Egyptians, they are Monophysite Christians.

”, “minerals”. They are considered in the physical and geographical characteristics of any region.

Definition 1

Geological structure - this is the structure of a section of the earth's crust, the features of the occurrence of rock layers, their mineralogical composition, and origin.

When studying the geological structure of the continents, the concepts of "platform", "folded area" are encountered.

Definition 2

Platform is a large, relatively immobile area of ​​the earth's crust.

Platforms underlie every continent. In the relief, the platforms correspond to plains.

Definition 3

Fold area - a mobile section of the earth's crust, where active mountain-building processes (earthquakes, volcanic eruptions) take place.

In the relief, folded areas are represented by mountain systems.

Definition 4

Relief is a set of irregularities in the earth's surface.

Definition 5

Minerals - this is the wealth of the earth's interior, which can be used by man to meet his needs.

Features of the geological structure of Africa

About $180 million years ago, the territory of Africa was integral part ancient supercontinent Gondwana. When Gondwana split, the African lithospheric plate separated. At the core modern territory Africa lies part of this plate, namely the ancient (Precambrian) African-Arabian platform .

In most of the territory, active mountain building stopped as early as $1000 - $500 million years ago. Later, the rigid core of the mainland did not experience folded processes.

The lower part of the platform, that is, its foundation, is made up of crystalline rocks – basalts and granites having igneous and metamorphic origin. They are very ancient in age. Due to weathering, continental sedimentary deposits accumulated on the basement, and marine sedimentary deposits accumulated in depressions. Over millions of years, they formed a powerful sedimentary cover on the platform. It should be noted that the sedimentary cover covers the foundation unevenly, because the platform experienced several slow ups and downs over a long period of time. In those areas where a long process of uplift took place, the ancient crystalline rocks of the basement appeared on the surface, thus forming shields.

Definition 6

The shield is the place where the crystalline foundation of the platform comes out to the surface.

On other parts of the platform, the processes of subsidence and flooding by the waters of the ancient seas took place. In these places, the foundation was covered by a huge thickness of marine sedimentary deposits, and slabs formed in such areas of the platform. After millions of years, the platform in its northwestern and southern parts was “completed” with parts of the ocean floor, while its sedimentary rocks were crumpled into folds and formed folded areas (area Atlas and Cape mountains ). More than $60 million years ago, the African-Arabian platform began to rise intensively. This rise was accompanied by giant faults in the earth's crust. During these faults, the largest system on land was formed East African faults (rifts) . It stretches for $4,000$ km from the Isthmus of Suez along the bottom of the Red Sea and overland to the Zambezi River. The width of the rifts in some places reaches up to $120$ km. The above faults, like a knife, cut through the African-Arabian platform. Along them there are earthquakes, manifestations of volcanism.

Relief of Africa

The relief of Africa is dominated by flat areas. This is due to the fact that almost the entire continent is based on a platform. A feature of the African plains is the predominance of high plains:

• hills,
• plateau,
• plateaus.

This can be explained by the general uplift of the entire territory of Africa in the Cenozoic. The lowlands extend only in narrow strips, mainly along the sea coasts.

The largest plains are located in the northern and western parts of the mainland. Their surface is very heterogeneous. At the same time, the alternation of highlands with lowlands and plateaus is characteristic of Africa. In places where the crystalline rocks of the foundation rise to the surface, Ahaggar and Tibesti highlands , with a height of more than $3000$ m. Among the high plateaus (up to $1000$ m) lies the marshy depression of the Congo. The Kalahari Basin is also surrounded on all sides by plateaus and plateaus.

A relatively small area in Africa is occupied by mountains. Has the highest scores East African plateau . On it are extinct volcanoes Kenya ($5199$ m) and kilimanjaro ($5895$ m) is the highest point in Africa.

These volcanic mountains are confined to the East African Rift Zone. Ethiopian highlands with numerous extinct volcanoes, it is uplifted by $2,000-3,000 m. In the northwestern part of the mainland rise atlas mountains (or the Atlas Mountains), formed at the junction of two lithospheric plates, in a place where Earth's crust was folded into folds. In the south of the mainland, low and flat-topped cape mountains . They look like cups turned upside down (hence the name). dragon mountains - higher, from the coast in giant ledges they descend to the hinterland of the mainland.

Minerals

The bowels of Africa are rich in a variety of minerals, their placement is closely related to the geological structure of the mainland. Deposits of ore minerals are confined to the ancient foundation of the platform. In particular, this applies to gold and ores such as:

• iron,
• copper,
• zinc,
• tin,
• chrome.

The largest deposits are concentrated in the south and east of Africa, in places where the basement is shallow. In particular, there are significant deposits gold and copper , in terms of the number of their reserves, Africa ranks first and second in the world, respectively. The bowels of the mainland are rich and uranium ores . Africa is famous for its deposits diamonds - Valuable gems.

Remark 1

They are used not only for the manufacture of expensive and exquisite jewelry, but also as materials unsurpassed in their hardness. Half of the world's diamonds are mined in Africa.

Their deposits are found on the southwestern coast and in the center of the mainland. Deposits of non-metallic minerals occur in sedimentary rocks, which cover the low areas of the platform with a thick cover. Such breeds in Africa include:

• coal,
• natural gas,
• oil,
• phosphorites and others.

There are huge deposits in the north of the Sahara and on the shelf of the Gulf of Guinea. The developed deposits of phosphorites, widely used in the production of fertilizers, are located in the north of the mainland. There are also ore minerals in the sedimentary strata, which were formed as a result of weathering processes of igneous and metamorphic rocks. For example, in the southern and western regions of Africa, deposits are known iron, copper, manganese ores and gold that are of sedimentary origin.