Features of the development of Africa determined the characteristic features of the structure of its surface. Most of the mainland is characterized by a flat relief with a wide development of leveling surfaces from Permian-Carboniferous and Triassic to Neogene and even Anthropogenic, with separately protruding blocky and volcanic mountains among them.

The main modern structural elements of the mainland are inherited from the beginning of the Paleozoic. They are similar to the corresponding structures of the East of South America, with which Africa remained united until the end of the Mesozoic. The northern, Sahara-Arabian part is characterized by the distribution of plates and syneclises with a Paleozoic and Phanerozoic cover (Sahara plate, Taudenny syneclise, Mali-Nigerian, Chad, etc.), between which there are uplifted sections of the Archean-Proterozoic basement (the Ahaggar, Regibatsky massifs). , Leono-Liberian, etc.).

The part of the mainland lying to the south-east of the line Cameroon - the northern tip of the Red Sea experienced a predominant upward trend and was subjected to strong tectonic activation, especially in the east. Syneclises occupy only the inner parts of the southern subcontinent, their axis runs along the 20th meridian. The northernmost and largest equatorial basin of the Congo is replaced in the south by less extensive ones - Okovango and others. Large uplifts in the east and south are the Nubian-Arabian shield, dissected by the Red Sea rift, the Mozambique Proterozoic folded belt, etc.

In the north and south Africa is surrounded by fold zones. In the south - this is the Paleozoic Cape region, in the north - the Atlas folded zone, which is part of the Mediterranean belt.

The main types of flat landforms within Africa are:

socle plains and plateaus on the Archeozoic and Proterozoic basement. Their heights in northern Africa usually do not exceed 500 m and very rarely reach 1000 m. Among the gently undulating crystalline surfaces, remnant mountains and ridges, composed of rocks most resistant to destruction, protrude. This type of relief is common in weakly activated massifs separating ancient syneclises; layered plains and elevations, horizontal or inclined and stepped, characteristic of the areas of distribution of the sedimentary cover along the periphery of ancient syneclises (for example, the Congo or Kalahari syneclises) and on the outskirts of the mainland, which experienced subsidence in the Mesozoic and the first half of the Cenozoic. This type of relief is also found on underground basement protrusions or in ancient troughs within large uplifts. Layered plains and uplands are young, with weak erosional dissection, and ancient, with deep and varied dissection; accumulative plains formed from the surface by Neogene and Anthropogenic marine or continental sediments. They occupy the central parts of ancient syneclises and the bottoms of rift zones, and are also located on the margins of the mainland, which were subjected to young transgressions.

Approximately 20% of Africa's surface is mountainous.

The revived mountains and highlands, formed as a result of Meso-Cenozoic and neotectonic uplifts, accompanied by faults and volcanism, are characteristic mainly of the eastern margin of Africa, along the rift zones crossing it. But separate sections of the mountainous relief are also located among the flat-platform areas, being associated with massifs that have experienced tectonic activation (Ahag-gar, Tibesti, Dragon Mountains, etc.). The types of morphostructure of the revived mountains are: socle blocky mountains and highlands formed in the areas of the basement outcrop; table mountains formed in the areas of distribution of sedimentary rocks and volcanic covers; volcanic mountains and volcanic plateaus confined to fault systems.

The Cape Mountains belong to a very rare type of revived mountains with an inherited folded structure, clearly expressed in the modern relief.

The Atlas region includes Paleozoic structures reworked by the Meso-Cenozoic movements to such an extent that they are considered part of the Mediterranean mountain belt. These older structures occupy the middle and southern parts of the Atlas region, while its northern chains are formations created mainly at the end of the Miocene - the beginning of the Pliocene. Within its boundaries, the following types of morphostructures are distinguished: folded and folded-blocky medium and high mountains, volcanic mountains, blocky massifs of attached sections of the platform, intermountain plateaus on Paleozoic structures leveled overlain by sedimentary rocks, accumulative plains of foothill and intermountain troughs.

The African continent has a complex of various minerals.

The oldest core of the platform, within East and South Africa, contains the largest reserves of iron ores, chromites, gold and uranium ores. The Upper Proterozoic structures, especially on the territory of the Republic of Zaire in East Africa, host deposits of ores of copper, tin, lead and other non-ferrous metals.

In the kimberlite pipes of the Mesozoic age, which penetrated the crystalline basement in different areas, primary deposits of diamonds were formed. The diamonds of South and East Africa are especially famous. Deposits of rare metals were formed along the boundaries of intrusive granite bodies of the same age.

No less significant are minerals of sedimentary origin, formed in the process of weathering of ancient crystalline rocks or deposited in the rocks of the sedimentary cover. The former include bauxites from West and East Africa; to the second - large deposits of oil and gas within the Sahara Plate, on the territory of Algeria, Libya and Egypt.

In the strata of the lagoon-continental Karoo formation, in South Africa, there are large reserves of coal.

In the synclinal zones of the Atlas folded region there are deposits of oil and phosphorites.

Africa is dominated by plains (Fig. 53). Large mountain ranges cover only a fifth of the territory of the mainland. This is due to the fact that the mainland is based on the ancient African-Arabian platform. It has been established that the thickness of its sedimentary cover in some places is 7000 m. Folded structures collapsed under the influence of external forces, forming high plains. They stretch for hundreds of kilometers. This is the uplands Tibesti.

In the north and west of the mainland, individual blocks of the platform sank more often, forming huge depressions. They were repeatedly flooded by the sea. Now heights up to 1000 m prevail here, and therefore this whole part of the mainland is called Low Africa.

The southern and eastern part of the mainland, where the average heights exceed 1000 m, is called High Africa. Here the platform rose and fell, as a result of which, over time, Ethiopian highlands and East African plateau. At the same time, individual blocks of the platform in East Africa were sinking, thanks to "the theme arose a whole system of deep faults in the earth's crust, which formed Great African Rift (Fig. 54). Here magma erupted and volcanoes erupted. Some of them have already died out, such as the highest peak in Africa - Mt. kilimanjaro, the height of which is 5895 m (Fig. 55).

In High Africa, there are both single peaks and large mountain ranges at the edges of the platform. For a significant height, they are called mountains. These are, for example, dragon mountains(Fig. 56). The slopes of the mountains resemble giant steps descending to the hinterland of the mainland. To the coast of the Indian Ocean, mountains often break off with sheer slopes. Also steep slopes have old cape mountains, extending along the southern edge of Africa. (Use the atlas map to determine their age.)

Africa is "spreading". This can be explained by the continental drift hypothesis. After the split of Gondwana, Africa, unlike other continents, moved relatively little, since it was more influenced by tensile forces, rather than compressive forces. And the cracks in the earth's crust are proof of these stretching forces. The Red Sea is also a consequence of these faults. Scientists believe that East Africa may someday separate from the rest of the mainland, as the Arabian Peninsula did earlier, and before it, the island of Madagascar.

Under the influence of wind and flowing waters, numerous small forms of the earth's surface were formed in Africa. On a large territory of Africa, the wind is in charge, forming the so-called eolian landforms. These are sandy hills, dunes, dunes, many of which occupy huge areas and reach the height of skyscrapers (Fig. 57).

• At the heart of the mainland lies an ancient platform, which determined the predominance of the flat relief of Africa.
• Volcanism contributed to the formation of high uplands and individual volcanic peaks.

On this page, material on the topics:

• The relief and geological structure of Africa briefly

• Briefly about the relief of Africa

• What are the main landforms of Africa that cross the Greenwich meridian

• Gdz compendium on the geography of the relief of Africa

• Geological development of Africa

Questions about this item:

The relief of Africa is predominantly homogeneous, smoothly turning into a mountainous surface, and quite young at that.

At the same time, there are few mountains in Africa, they are mainly formed in the north of the mainland.

There are also mountains in the southern part of the continent, but throughout the mainland the mountain complexes are low.

The main reason for the absence of the formation of relief irregularities (folds, which subsequently become mountains) is the presence of the mainland on one fairly homogeneous plate.

The main characteristics of the relief of Africa can be noted in this form:

• the continent is located on average at an altitude of 750 meters above sea level (only Eurasia and Antarctica are higher);
• 5895 meters - the height of Mount Kilimanjaro - the highest point on the mainland;
• many are located evenly throughout the mainland despite the predominance of deserts;
• Africa is divided into low and high (most of it is low - about 60%).

Highlands of Africa

Africa is a flat continent. There are not even lowlands here - a continuous plateau.

This also applies to the island of Madagascar - the largest off the African mainland. The island belongs to him, like the Seychelles and the Arabian Peninsula.

The African-Arabian platform is rising to the south. Closer to the eastern part, it becomes quite high - it approaches the mark of 1000 meters above sea level in height. At the same time, the flat surface is preserved.

The highest peak in Africa -. It is located in the east, closer to the southern part of the continent.

Here the area is called the Ethiopian Highlands. The highlands here are not entirely calm.

The territory is seismically active, so there are frequent earthquakes that set off local volcanoes.

Such surface features are reflected even in the Sahara desert, on the territory of which there are two large highlands - Ahaggar and Tibesti.

Mountainous relief of Africa

Time has little effect on what kind of relief in Africa can be seen today. Mountain surfaces are gradually destroyed, but they still exist due to the formation of new, young ones.

These are the Drakensberg and Cape Mountains, located literally on the shores of the Indian Ocean.

This place attracts tourists due to its unusual relief and unprecedented beauty.

At the same time, at a distance from the coast, the mountainous surface gradually descends, turning into a plain closer to the desert.

Cape Mountains. This mountain surface is one of the few that has preserved the kind of mountains located here in ancient times. However, this does not indicate a great age of the relief.

Previously, there were higher, folded mountains in this place, today their shape has remained, but relatively young uplands have formed in the same place.

The highest point is Mount Kompasberg, which rises 2500 meters above sea level.

Atlas Mountains. This mountain structure is still being formed in the northern part of the mainland: where the mountains begin - Morocco, then they stretch to Tunisia.

At the same time, the hills are formed on the ridge, which begins on the Eurasian continent - in the east of Europe.

lowland relief of africa

There are few lowlands in Africa. As a percentage of the occupied territory, they occupy only 9% of the mainland.

The lowest point is Lake Assal (near the Red Sea, the state of Djibouti).

Also, lowlands can be found in Central Africa, but they do not differ in large scale and quantity.

River relief of Africa

Nile. 6670 meters - the length of this largest river in the world. It flows predominantly in the north and east. Crosses many countries.

It is of great importance for the supply of water to areas where agriculture is concentrated, livestock is raised.

It was near that the ancient Egyptian civilization developed and formed.

The Nile crosses the Sahara, through which no river flows anymore, but it flows into the Mediterranean Sea.

Congo. 4373 meters - the length of this river, it flows into the Atlantic Ocean. In terms of basin area, the river is considered the second in the world, taking pride of place after the American Amazon.

The Congo crosses the equator twice. It is distributed over the Southern and Northern Hemispheres, due to which it is very full-flowing.

The fact is that in the Southern Hemisphere and in the Northern Hemisphere at different times there are heavy rains, and the climate is significantly different.

This makes it possible for the river to be fed by different sources at different times of the year.

You can also add Niger, which is located in the western part of the continent, to the list where they belong. 4160 meters is the length of the river and it crosses many countries.

The Zambezi is the longest river in Africa that flows into the Indian Ocean. 2735 kilometers - its length.

A distinctive feature of the reservoir - on this river is the Victoria Falls with a height of 120 meters and a width of 1.8.

Africa is dominated by plains, there are almost no mountain ranges. The mainland is located on the ancient African-Arabian platform, which is the remains of ancient mountains.

That is why mountain-building processes on the mainland are very poorly developed - young mountains grow only in the north of the continent.

Highlands and plateaus of Africa

More than 4/5 of Africa is occupied by plateaus. Lowlands on the mainland are virtually absent. Not only the mainland is located on the African-Arabian platform, but also Madagascar, the Seychelles and the Arabian Peninsula.

The African Highlands are located in the southeastern part of the mainland. The average heights here exceed 1000 m above sea level. In this region, the African-Arabian platform rises somewhat.

The Ethiopian highlands are located in southeastern Africa. This part of the mainland is called High Africa, it is here that the highest peak of the continent, Mount Kilimanjaro, is located.

These areas are characterized by frequent earthquakes, which provoke the eruptions of the Karisimbi and Cameroon volcanoes. Highlands are also found in the Sahara desert, the highest of them being the Tibesti and Ahaggar highlands.

Mountains of Africa

On the coast of the Indian Ocean are the Cape and Dragon Mountains - their height decreases towards the center of the mainland. The Cape Mountains formed during the Upper Paleozoic.

The region of the Cape Mountains is characterized by a Mediterranean type of climate. The Cape Mountains are a vivid example of the revived mountains that were formed on the ancient destroyed mountain systems and inherited from them the folded structure that can be traced in the modern relief.

The highest peak of the Cape Mountains is Mount Compasberg, whose height reaches 2500 m. In the north of the mainland, as a result of the displacement of the spirit of the lithospheric plates, young Atlas Mountains were formed.

These mountains are a continuation of the young mountains of Europe, which are located in the Gibraltar region. The length of the mountain ranges of the Atlas Mountains is 2500 km: they originate in the north of Morocco and stretch to Tunisia.

The highest peak of the Atlas Mountains is Mount Toubkal (4100m). Due to tectonic faults, earthquakes often occur in the Atlas Mountains region.

Lowlands of Africa

The lowlands of Africa occupy only 9% of its territory. The lowest point of the continent is the salt lake Assal, which is located on the territory of the state of Djibouti (Red Sea coast). Lowlands are also common in some countries of Central Africa.

Block #1 AFRICA

PRACTICAL WORK №1 "OROGRAPHIC OBJECTS OF AFIKA"

Run a contour map (Grade 7) "Orographic objects of Africa" ​​- designate the main landforms, according to the given nomenclature. According to the atlas of the 7th class, apply a scale of heights and paint over the contour map in accordance with the indicated relief forms.

Peninsulas, capes

1. Ras Engela (El Abyad). The northernmost point of the mainland (37 0 21 "N, 9 0 45" E).

2. Green Cape (Almadi). The westernmost point of Africa (14 0 45" N, 17 0 32" W).

3. Good Hope Cape . In 1488, the Portuguese navigator V. Dias reached this cape on his way to India and named it Cape of Storms: storms from the Atlantic and Indian oceans met here. But the king of Portugal did not approve this harsh and true name, fearing a disadvantageous impression that would harm the colonial enterprises, and gave the name Cape of Good Hope hope to reach India. Located in the extreme south of Africa.

4. Igolny, cape. It was named by Portuguese navigators who noticed a magnetic anomaly near it - the deviation of the compass needle (needle). The southernmost point of the mainland (34 0 52 "S, 19 0 59" E).

5. Somalia, peninsula. "Dark, black" according to the skin color of the population.

6. Ras Hafun, cape. The easternmost point of Africa (10 0 26 "N, 51 0 23" E).

Mountain systems, highlands, uplands

Atlas Mountains:

1. High Atlas .

2. Toubkal (4165 m). The highest point of the Atlas Mountains.

Highlands, uplands:

1. Ahaggar. Highlands in the Sahara (highest point 2918 m).

2. Tibesti. Highlands in the Sahara.

3. Emi-Kushi (Emi-Usi) (3415 m). The highest point of the Tibesti highlands.

4. Cameroon, volcano (4070 m). It is located near the coast of the Gulf of Guinea.

5. South Guinean plateau . Located in the west of the Congo Basin.

6. Ethiopian (Abyssinian) highlands.

7. Ras Dashen (4620 m). The highest point of the Ethiopian highlands.

8. East African Highlands .

9. Kilimanjaro (5895 m), volcano . The highest peak in Africa.

10. Kenya (5199 m). Located in East Africa.

11. Karishimbi (4507 m) . One of the volcanoes of the Virunga massif.

12. dragon mountains . Located in South Africa, heights up to 3482 m.

13. cape mountains . Mountains in southern Africa, heights 2325 m.

Lowlands, plains, plateaus

1. high plateaus . Plateau between the Middle Atlas and Saharan Atlas and Anti-Atlas ranges.

2. Algiers-Tunisian lowland .

3. Libyan lowland .

4. Kattara (-133 m), depression. The lowest point in Africa, is located within the Libyan lowland.

5. Senegal-Mauritanian lowland .

6. Guinean lowland .

7. mozambican lowland .

8. Somali lowland.

9. Darfur, plateau . It is located to the east of the basin of Lake Chad. Altitudes up to 3088 m (Marra).

10. Sahel. Plateau in the western Sahara.

11. Chad, plain . In its central part is Lake Chad.

12. Bodele, basin . The lowest part of the plain of Chad.

13. Kalahari, plain . Located in South Africa.