Africa-1.4 Billion-Nigeria (15.38%) Ethiopia (8.37%) Egypt (7.65%) Con…
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Africa-1.4 Billion-Nigeria (15.38%) Ethiopia (8.37%) Egypt (7.65%)
Democratic Republic of the Congo (6.57%) Tanzania (4.55%) S
outh Africa (4.47%) Kenya (3.88%) Uganda (3.38%) Algeria (3.36%) Other
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Egypt, a country linking northeast Africa with the Middle East, dates to the time of the pharaohs. Millennia-old monuments sit along the fertile Nile River Valley, including Giza's colossal Pyramids and Great Sphinx as well as Luxor's hieroglyph-lined Karnak Temple and Valley of the Kings tombs. The capital, Cairo, is home to Ottoman landmarks like Muhammad Ali Mosque and the Egyptian Museum, a trove of antiquities. ― Google
Capital: Cairo
President: Abdel Fattah El-Sisi
Population: 102.3 million (2020) World Bank
Currency: Egyptian pound
Official language: Modern Standard Arabic
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South Africa is a country on the southernmost tip of the African continent, marked by several distinct ecosystems. Inland safari destination Kruger National Park is populated by big game. The Western Cape offers beaches, lush winelands around Stellenbosch and Paarl, craggy cliffs at the Cape of Good Hope, forest and lagoons along the Garden Route, and the city of Cape Town, beneath flat-topped Table Mountain. ― Google
President: Cyril Ramaphosa Trending
Capitals: Cape Town, Pretoria, Bloemfontein
Dialing code: +27
Currency: South African rand
Population: 59.31 million (2020) World Bank
Official languages: Afrikaans, English, Xhosa, Zulu, Southern Sotho, Northern Sotho, Tsonga, Tswana, Venda, Swati, Ndebele
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Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km² including adjacent islands, it covers 6% of Earth's total surface area and 20% of its land area. With 1.4 billion people as of 2021, it accounts for about 18% of the world's human population. Wikipedia
Area: 30.37 million km²
Population: 1.216 billion (2016)
Languages: English; French; Spanish; Portuguese; Swahili; Arabic; 1250–3000 native languages
Largest city: Lagos
Religions: Christianity (49%); Islam (42%); Traditional faiths (8%); Others (1%);
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https://en.wikipedia.org/wiki/Africa
Africa - Wikipediahttps://en.wikipedia.org › wiki › Africa
africa from en.wikipedia.org
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) ...
Population: 1,393,676,444 (2021; 2nd)
GDP per capita: $2,180 (2022 est; 6th)
Population density: 46.1/km2 (119.4/sq mi) ...
Countries: 54+2*+5** (*disputed) (**territories)
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Africa, the second largest continent (after Asia), covering about one-fifth of the total land surface of Earth. The continent is bounded on the west by the Atlantic Ocean, on the north by the Mediterranean Sea, on the east by the Red Sea and the Indian Ocean, and on the south by the mingling waters of the Atlantic and Indian oceans.
Africa’s total land area is approximately 11,724,000 square miles (30,365,000 square km), and the continent measures about 5,000 miles (8,000 km) from north to south and about 4,600 miles (7,400 km) from east to west. Its northern extremity is Al-Ghīrān Point, near Al-Abyaḍ Point (Cape Blanc), Tunisia; its southern extremity is Cape Agulhas, South Africa; its farthest point east is Xaafuun (Hafun) Point, near Cape Gwardafuy (Guardafui), Somalia; and its western extremity is Almadi Point (Pointe des Almadies), on Cape Verde (Cap Vert), Senegal. In the northeast, Africa was joined to Asia by the Sinai Peninsula until the construction of the Suez Canal. Paradoxically, the coastline of Africa—18,950 miles (30,500 km) in length—is shorter than that of Europe, because there are few inlets and few large bays or gulfs.
Off the coasts of Africa a number of islands are associated with the continent. Of these Madagascar, one of the largest islands in the world, is the most significant. Other, smaller islands include the Seychelles, Socotra, and other islands to the east; the Comoros, Mauritius, Réunion, and other islands to the southeast; Ascension, St. Helena, and Tristan da Cunha to the southwest; Cape Verde, the Bijagós Islands, Bioko, and São Tomé and Príncipe to the west; and the Azores and the Madeira and Canary islands to the northwest.
The continent is cut almost equally in two by the Equator, so that most of Africa lies within the tropical region, bounded on the north by the Tropic of Cancer and on the south by the Tropic of Capricorn. Because of the bulge formed by western Africa, the greater part of Africa’s territory lies north of the Equator. Africa is crossed from north to south by the prime meridian (0° longitude), which passes a short distance to the east of Accra, Ghana.
Mount Kenya in Mount Kenya National Park is the highest mountain in Africa. UNESCO World Heritage Site. Giant Lobelia in foreground. (Mt. Kenya; Mt. Kenya National Park; mountains; rugged mountain; African geography, African landscape, stratovolcano)
BRITANNICA QUIZ
Africa’s Physical Features
Can you identify the location of some of Africa’s noted physical features? Match the feature to the country it’s found in.
In antiquity the Greeks are said to have called the continent Libya and the Romans to have called it Africa, perhaps from the Latin aprica (“sunny”) or the Greek aphrike (“without cold”). The name Africa, however, was chiefly applied to the northern coast of the continent, which was, in effect, regarded as a southern extension of Europe. The Romans, who for a time ruled the North African coast, are also said to have called the area south of their settlements Afriga, or the Land of the Afrigs—the name of a Berber community south of Carthage.
The whole of Africa can be considered as a vast plateau rising steeply from narrow coastal strips and consisting of ancient crystalline rocks. The plateau’s surface is higher in the southeast and tilts downward toward the northeast. In general the plateau may be divided into a southeastern portion and a northwestern portion. The northwestern part, which includes the Sahara (desert) and that part of North Africa known as the Maghrib, has two mountainous regions—the Atlas Mountains in northwestern Africa, which are believed to be part of a system that extends into southern Europe, and the Ahaggar (Hoggar) Mountains in the Sahara. The southeastern part of the plateau includes the Ethiopian Plateau, the East African Plateau, and—in eastern South Africa, where the plateau edge falls downward in a scarp—the Drakensberg range. One of the most remarkable features in the geologic structure of Africa is the East African Rift System, which lies between 30° and 40° E. The rift itself begins northeast of the continent’s limits and extends southward from the Eritrean Red Sea coast to the Zambezi River basin.
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Africa contains an enormous wealth of mineral resources, including some of the world’s largest reserves of fossil fuels, metallic ores, and gems and precious metals. This richness is matched by a great diversity of biological resources that includes the intensely lush equatorial rainforests of Central Africa and the world-famous populations of wildlife of the eastern and southern portions of the continent. Although agriculture (primarily subsistence) still dominates the economies of many African countries, the exploitation of these resources became the most significant economic activity in Africa in the 20th century.
Climatic and other factors have exerted considerable influence on the patterns of human settlement in Africa. While some areas appear to have been inhabited more or less continuously since the dawn of humanity, enormous regions—notably the desert areas of northern and southwestern Africa—have been largely unoccupied for prolonged periods of time. Thus, although Africa is the second largest continent, it contains only about 10 percent of the world’s population and can be said to be underpopulated. The greater part of the continent has long been inhabited by Black peoples, but in historic times there also have occurred major immigrations from both Asia and Europe. Of all foreign settlements in Africa, that of the Arabs has made the greatest impact. The Islamic religion, which the Arabs carried with them, spread from North Africa into many areas south of the Sahara, so that many western African peoples are now largely Islamized.
This article treats the physical and human geography of Africa, followed by discussion of geographic features of special interest. For discussion of individual countries of the continent, see such articles as Egypt, Madagascar, and Sudan. African regions are treated under the titles Central Africa, eastern Africa, North Africa, Southern Africa, and western Africa; these articles also contain the principal treatment of African historical and cultural development. For discussion of major cities of the continent, see such articles as Alexandria, Cairo, Cape Town, Johannesburg, and Kinshasa. Related topics are discussed in the articles literature, African; literature, South African; architecture, African; art, African; dance, African; music, African; theatre, African; art and architecture, Egyptian; Islam; arts, Islamic; and Islamic world.
Davidson S.H.W. Nicol
The Editors of Encyclopaedia Britannica
Geologic history
General considerations
Ruwenzori Range
Ruwenzori Range
The African continent essentially consists of five ancient Precambrian cratons—Kaapvaal, Zimbabwe, Tanzania, Congo, and West African—that were formed between about 3.6 and 2 billion years ago and that basically have been tectonically stable since that time; those cratons are bounded by younger fold belts formed between 2 billion and 300 million years ago. All of those rocks have been extensively folded and metamorphosed (that is, they have been modified in composition and structure by heat and pressure). Precambrian rock outcrops appear on some 57 percent of the continent’s surface, while the rest of the surface consists of largely undeformed younger sediments and volcanic rocks.
The oldest rocks are of Archean age (i.e., about 4.6 to 2.5 billion years old) and are found in the so-called granite-gneiss-greenstone terrains of the Kaapvaal, Zimbabwe, and Congo cratons. They consist of gray, banded gneisses, various granitoids, and rather well-preserved volcanic rocks that show evidence of submarine extrusion (i.e., emission of rock material in molten form) and formation under high temperatures. The rock type komatiite is particularly diagnostic of those volcanic sequences and is almost exclusively restricted to the Archean Eon. The cratons were tectonically stabilized by voluminous granite intrusions toward the end of the Archean and were then covered by clastic sediments, some of which contain economically important gold and uranium deposits (e.g., the Witwatersrand System in South Africa).
The Proterozoic Eon (2.5 billion to about 541 million years ago) is characterized by the formation of several mobile belts, which are long, narrow zones of strongly deformed and metamorphosed rocks that occur between the cratons and probably resulted from the collision between the cratons due to plate tectonic processes. The oldest mobile belts are found in Archean rocks, such as the Limpopo belt separating the Kaapvaal from the Zimbabwe craton. Younger belts were formed during a continentwide thermotectonic event known as the Eburnian (2.2 to 1.8 billion years ago), which gave rise to the Birimian assemblage in western Africa, the Ubendian assemblage in east-central Africa, and large volumes of rocks in Angola. Still younger belts of the Kibaran thermotectonic event (1.2 billion to 950 million years ago) are found in eastern and Southern Africa.
The end of the Precambrian was marked by a major event of mobile-belt formation known as the Pan-African episode (about 950 to 550 million years ago), which generated long fold belts, such as the Mozambique belt along the east coast of Africa, the Damara and Katanga belts extending from Namibia into the Democratic Republic of the Congo and Zambia, the West Congo belt between Angola and Gabon, the Dahomey-Ahaggar belt between Ghana and Algeria, and the Mauritanide belt from Senegal to Morocco.
A unique late Precambrian evolution is recorded in the so-called Arabian-Nubian Shield of northeastern Africa and Arabia. There, large volumes of volcanic and granitoid rocks were generated in an island-arc, marginal-basin setting—an environment similar to that of the present southwestern Pacific Ocean. Rocks were accreted onto the ancient African continent, the margin of which was then near the present Nile River, by subduction processes identical to those observed today. (Subduction involves the descent of the edge of one lithospheric plate beneath that of another where two such plates collide.)
The interiors of the ancient cratons were not affected by the above tectonic events, and intracratonic sedimentary and volcanic sequences accumulated in large basins. The most important of those are the Transvaal basin on the Kaapvaal craton that contains economically important iron ore deposits; the Congo basin; and the West African basin, with its thick late Proterozoic sediments including a prominent tillite horizon that marks a major glaciation event at the end of the Precambrian.
Little Karoo
Little Karoo
After the Precambrian, Africa’s geologic history is characterized by the following events: the formation of fold belts in the Paleozoic Era (about 541 to 252 million years ago) in South Africa (the Cape fold belt), Morocco (the Anti-Atlas belt), and Mauritania (the Mauritanide belt) bordering the older cratons; voluminous basaltic volcanism some 230 to 200 million years ago in South Africa, Namibia, and East Africa, known as the Karoo System, that was probably related to the beginning of the breakup of the Gondwana supercontinent; the formation of a young mountain belt in northwestern Africa some 100 to 40 million years ago as a result of collision between the African and European plates, together with the closure of the ancestral Mediterranean Sea (the Tethys Sea); and the development of the East African Rift System during the Cenozoic Era (i.e., roughly the past 66 million years), leading to the opening of the Red Sea, the northeast drift of the Arabian Plate, and the fracturing of the ancient crust of Africa along several long rift valleys, accompanied by extensive volcanism.
Rock types and structural evolution
The Precambrian
The oldest rocks consist of gneisses, granites, metasediments, and metavolcanic rocks 3.6 to 2.5 billion years old; all are variably deformed and metamorphosed to some degree. The best-preserved assemblages occur in the Kaapvaal and Zimbabwe cratons and contain large deposits of gold and sulfide minerals. The volcanic suites are dominated by basaltic and komatiitic lavas, often interlayered with metasediments and generally referred to as greenstone belts. Those structures are often found together with layered gneisses, or they are intruded by granitoid plutons. Several generations of greenstones have been recognized. The oldest formed about 3.4 billion years ago, the second some 3 to 2.9 billion years ago, and the third some 2.7 to 2.6 billion years ago. Some of the oldest traces of life are preserved as unicellular algae in Precambrian cherts of the Barberton greenstone belt in the Transvaal region of South Africa. The end of the Archean is marked by voluminous granite intrusions, after which Africa’s cratons became tectonically stable. One of the most spectacular features marking the end of the Archean is the intrusion of the Great Dyke in Zimbabwe, a large, layered body of mafic-ultramafic rocks with substantial deposits of chromium, asbestos, and nickel. It is still not clear whether Archean evolution was characterized by the same plate tectonic processes that are seen today, and there are suggestions that the greenstone belts are remnants of ancient oceanic crust. Cratonic (essentially undeformed) sediments appear in the stratigraphic record for the first time in the late Archean and are best developed in the Kaapvaal craton of Southern Africa.
The early Proterozoic (about 2.5 to 1.6 billion years ago) is characterized by cratonic clastic sediments on the stable cratons—the best examples are the Witwatersrand-Ventersdorp-Transvaal basin of Southern Africa and the Francevillian basin in Gabon—and by metavolcanic-metasedimentary rocks and granitoids in noncratonic areas such as the extensive Birimian terrain of western Africa extending from Senegal to Ghana. Of particular interest are extensive stromatolite-bearing limestones and economically important iron formations in the Transvaal sequence of South Africa that provide evidence for an oxygen-rich atmosphere by about 2.2 billion years ago. About 2 billion years ago the Bushveld Complex—which is one of the largest differentiated igneous bodies on Earth, containing major deposits of platinum, chromium, and vanadium—was emplaced in the northern Kaapvaal craton. The middle part of the early Proterozoic was dominated by powerful orogenic (mountain-building) processes that gave rise to fold belts in which sedimentary and volcanic rocks originally deposited in deep basins along the continental margins were severely deformed, metamorphosed, intruded by granitoid plutons, and finally uplifted into mountain ranges, probably as a result of continental collision. That Eburnian event was particularly active in western Africa, where it deformed the Birimian assemblages; but it was also active in eastern Africa, where it generated the Ubendian belt in southern Tanzania, and in southwestern Africa, where it formed major rock units in Angola and northern Namibia. By the end of the early Proterozoic, the Archean crustal blocks had grown into cratons of considerable size.
The record of the middle Proterozoic (about 1.6 to 1 billion years ago) shows deposition of continental sediments and volcanic rocks on the cratons and adjacent to the earlier fold belts (molasse deposits). Undeformed or only mildly folded successions are found in Southern Africa (Waterberg and Matsap sequences), in northern Zambia, and in the Democratic Republic of the Congo. Elsewhere, sedimentary and volcanic sequences were deposited in elongate basins that were later subjected to intense deformation and metamorphism during the Kibaran event. That important thermotectonic episode gave rise to the Kibaran-Burundian fold belt in east-central Africa, the Ruwenzori belt in Uganda, and the Namaqua-Natal belt in South Africa and Namibia.
The late Proterozoic (about 1 billion to 541 million years ago) is again characterized by platform deposits in stable areas, such as the West African craton (Taoudeni and Tindouf basins), the Congo craton, the Kalahari craton (Nama basin of Namibia), and the Tanzania craton (Bukoban beds). Tectonic and magmatic activity was concentrated in mobile belts surrounding the stable areas and took place throughout the late Proterozoic, during the so-called Pan-African thermotectonic event. Long, linear belts—such as the Damara-Katanga of central and southwestern Africa, the Mozambique belt of eastern Africa, and the Dahomey-Ahaggar belt of western Africa—formed during that time, and some of those belts contain diagnostic rock assemblages that indicate that they resulted from continental collisions. Many late Precambrian sequences of Africa contain one or two beds of tillites (sedimentary rocks that are composed of lithified clay and rock sediments produced by the action of ice), which are thought to have resulted from an extensive glaciation that covered much of Africa at that time. In the Arabian (Eastern) Desert of Egypt and in the Red Sea Hills of Sudan, a predominance of volcanic rocks and granitoids, together with frequent remnants of ancient oceanic crust, document an evolution similar to what is now occurring in the island-arc systems of the southwestern Pacific. Those rocks clearly demonstrate that plate tectonic processes operated in the late Precambrian.
The Paleozoic Era
Table Mountain
Table Mountain
The Paleozoic Era consists of the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian periods and includes two major mountain-building episodes. The continent of Africa may be said to have taken shape during the Paleozoic. A glacial period during the Ordovician is evidenced by widespread deposition tillites, which may be seen in southern Morocco, throughout western Africa, and in subequatorial Africa as far south as Namibia. That tillite sequence marks the transition from the end of the Precambrian to the beginning of the Cambrian Period.
Marine fossils of the Cambrian Period (about 541 to 485 million years ago) are found in southern Morocco, the Western and Mauritanian Sahara, and Namibia. In Egypt and in the Arabian Peninsula their presence has been revealed by drilling. Elsewhere they remain unknown.
During the Ordovician Period (about 485 to 444 million years ago), fossiliferous marine sandstone completely covered northern and western Africa, including the Sahara. The Table Mountain sandstone of South Africa constitutes its only other trace. That period is, in addition, remarkable for broad, large-scale deformation of the African crust, which raised the continental table of the central and western Sahara by approximately 5,000 feet (1,500 metres). Each emergence resulted in the creation of valleys that became flooded when the continent subsided. Toward the end of the period, the Sahara became glaciated, and tillites and sandstones filled the valleys. A complete change of sedimentation characterized the Silurian Period (about 444 to 419 million years ago), which is indicated by the deposits of graptolitic shales (those containing small fossil colonies of extinct marine animals of uncertain zoological affinity) in the Arabian Peninsula and in northwestern Africa.
Marine fossils of the Devonian Period (about 419 to 359 million years ago) are found in North Africa and in the Sahara. Traces also have been discovered in parts of Guinea, Ghana, and Arabia, as well as in Gabon; they also occur in the Bokkeveld Series of South Africa. Fossilized plants that include Archaeosigillaria (ancient club mosses) may be traced in formations of the earlier Devonian Period in the Sahara and in South Africa (Witteberg Series).
Mount Kenya in Mount Kenya National Park is the highest mountain in Africa. UNESCO World Heritage Site. Giant Lobelia in foreground. (Mt. Kenya; Mt. Kenya National Park; mountains; rugged mountain; African geography, African landscape, stratovolcano)
BRITANNICA QUIZ
Africa’s Physical Features
Can you identify the location of some of Africa’s noted physical features? Match the feature to the country it’s found in.
The Carboniferous Period (about 359 to 299 million years ago) was marked by the onset of several major tectonic events. Evidence of marine life that existed in the earlier part of the period comes from fossils found in North Africa, the central and western Sahara, and Egypt. During the middle and later parts of the Carboniferous, the Hercynian mountain-building episodes occurred as a result of collision between the North American and African plates. The Mauritanide mountain chain was compressed and folded at that time along the western margin of the West African craton from Morocco to Senegal. Elsewhere, major uplift or subsidence occurred, continuing until the end of the Triassic Period (i.e., about 201 million years ago). Those structures were synformal (folded with the strata dipping inward toward a central axis) in the Tindouf and Taoudeni basins of western Algeria, Mauritania, and Mali and antiformal (forming a mountainous spine or dome) at Reguibat in eastern Western Sahara.
The late Carboniferous Period is represented throughout the Sahara by layers of fossilized plants and sometimes—as in Morocco and Algeria—by seams of coal. Different phenomena may be observed, however, in the region of subequatorial Africa, including the Dwyka tillite, which covers part of South Africa, Namibia, Madagascar, an extensive portion of the Congo Basin, and Gabon. At several places in South Africa, the Dwyka strata are covered by thin marine layers that serve to demarcate the transition from the Carboniferous to the Permian Period and that form the beginning of the great Karoo System.
Marine fossils of the Permian Period (about 299 to 252 million years ago) are visible in southern Tunisia, in Egypt, in the Arabian Peninsula, on the coasts of Tanzania, and in the Mozambique Channel. Elsewhere, traces of the Permian are of continental rather than marine origin and are included in the Karoo System in South Africa. There, the lower Permian strata are known as the Ecca Series and are divided into three groups: the Lower Ecca (containing almost 1,000 feet [300 metres] of shales), the Middle Ecca (some 1,650 feet [500 metres] of sandstone, seams of coal, and fossilized plants), and the Upper Ecca (about 650 feet [200 metres] of shales again).
The upper Permian is represented by the lower part of the Beaufort Series, which continued forming into the early Triassic Period. The Beaufort Series is almost 10,000 feet (3,000 metres) thick and is famous for its amphibian and reptile fossils; a similar series is also found in southern Russia. Other Permian formations, not as rich in coal, occur in the Democratic Republic of the Congo, Tanzania, Kenya, Uganda, Zambia, Zimbabwe, Mozambique, and Madagascar.
The absence of primary marine formations throughout Southern Africa should be emphasized. It is not yet known whether that absence is due to a hiatus in deposition or to erosion.
The Mesozoic Era
The Mesozoic Era (about 252 to 66 million years ago) is divided into three periods—the Triassic, Jurassic, and Cretaceous—and is remarkable for the transgression of ancient seas and for the emergence of massive land formations containing interesting fossil remains.
Marine formations
During the Triassic Period (about 252 to 201 million years ago), ancient seas left deposits of marine formations in North Africa, the southern Sahara, Egypt, Arabia, and parts of Tanzania and northern Madagascar. Deposits from the Jurassic Period (about 201 to 145 million years ago) extend to the Atlantic basins of the Río de Oro region of Western Sahara and Senegal along the northwest coast of the continent. In the middle of the Jurassic a great transgression of the Indian Ocean extended over Somalia and much of Ethiopia. That event was followed by a series of marine transgressions in the Cretaceous Period (about 145 to 66 million years ago), including those along the coasts of equatorial Africa when Gondwana broke up and the present Atlantic and Indian oceans took shape; during one transgression a shallow sea covered much of the northern and central Sahara and Egypt as far south as Sudan; and a later one again covered the same areas, as well as western Arabia and the west coast of Madagascar.
Continental formations
In Africa north of the Equator and in Arabia, Mesozoic continental formations covered large areas. During the Triassic the Saharan Zarz
South Africa · Africa (disambiguation) · Demographics of Africa · North Africa
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Africa-1.4 Billion-Nigeria (15.38%) Ethiopia (8.37%) Egypt (7.65%)
Democratic Republic of the Congo (6.57%) Tanzania (4.55%) S
outh Africa (4.47%) Kenya (3.88%) Uganda (3.38%) Algeria (3.36%) Other
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Egypt, a country linking northeast Africa with the Middle East, dates to the time of the pharaohs. Millennia-old monuments sit along the fertile Nile River Valley, including Giza's colossal Pyramids and Great Sphinx as well as Luxor's hieroglyph-lined Karnak Temple and Valley of the Kings tombs. The capital, Cairo, is home to Ottoman landmarks like Muhammad Ali Mosque and the Egyptian Museum, a trove of antiquities. ― Google
Capital: Cairo
President: Abdel Fattah El-Sisi
Population: 102.3 million (2020) World Bank
Currency: Egyptian pound
Official language: Modern Standard Arabic
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South Africa is a country on the southernmost tip of the African continent, marked by several distinct ecosystems. Inland safari destination Kruger National Park is populated by big game. The Western Cape offers beaches, lush winelands around Stellenbosch and Paarl, craggy cliffs at the Cape of Good Hope, forest and lagoons along the Garden Route, and the city of Cape Town, beneath flat-topped Table Mountain. ― Google
President: Cyril Ramaphosa Trending
Capitals: Cape Town, Pretoria, Bloemfontein
Dialing code: +27
Currency: South African rand
Population: 59.31 million (2020) World Bank
Official languages: Afrikaans, English, Xhosa, Zulu, Southern Sotho, Northern Sotho, Tsonga, Tswana, Venda, Swati, Ndebele
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Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km² including adjacent islands, it covers 6% of Earth's total surface area and 20% of its land area. With 1.4 billion people as of 2021, it accounts for about 18% of the world's human population. Wikipedia
Area: 30.37 million km²
Population: 1.216 billion (2016)
Languages: English; French; Spanish; Portuguese; Swahili; Arabic; 1250–3000 native languages
Largest city: Lagos
Religions: Christianity (49%); Islam (42%); Traditional faiths (8%); Others (1%);
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https://en.wikipedia.org/wiki/Africa
Africa - Wikipediahttps://en.wikipedia.org › wiki › Africa
africa from en.wikipedia.org
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) ...
Population: 1,393,676,444 (2021; 2nd)
GDP per capita: $2,180 (2022 est; 6th)
Population density: 46.1/km2 (119.4/sq mi) ...
Countries: 54+2*+5** (*disputed) (**territories)
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Africa, the second largest continent (after Asia), covering about one-fifth of the total land surface of Earth. The continent is bounded on the west by the Atlantic Ocean, on the north by the Mediterranean Sea, on the east by the Red Sea and the Indian Ocean, and on the south by the mingling waters of the Atlantic and Indian oceans.
Africa’s total land area is approximately 11,724,000 square miles (30,365,000 square km), and the continent measures about 5,000 miles (8,000 km) from north to south and about 4,600 miles (7,400 km) from east to west. Its northern extremity is Al-Ghīrān Point, near Al-Abyaḍ Point (Cape Blanc), Tunisia; its southern extremity is Cape Agulhas, South Africa; its farthest point east is Xaafuun (Hafun) Point, near Cape Gwardafuy (Guardafui), Somalia; and its western extremity is Almadi Point (Pointe des Almadies), on Cape Verde (Cap Vert), Senegal. In the northeast, Africa was joined to Asia by the Sinai Peninsula until the construction of the Suez Canal. Paradoxically, the coastline of Africa—18,950 miles (30,500 km) in length—is shorter than that of Europe, because there are few inlets and few large bays or gulfs.
Off the coasts of Africa a number of islands are associated with the continent. Of these Madagascar, one of the largest islands in the world, is the most significant. Other, smaller islands include the Seychelles, Socotra, and other islands to the east; the Comoros, Mauritius, Réunion, and other islands to the southeast; Ascension, St. Helena, and Tristan da Cunha to the southwest; Cape Verde, the Bijagós Islands, Bioko, and São Tomé and Príncipe to the west; and the Azores and the Madeira and Canary islands to the northwest.
The continent is cut almost equally in two by the Equator, so that most of Africa lies within the tropical region, bounded on the north by the Tropic of Cancer and on the south by the Tropic of Capricorn. Because of the bulge formed by western Africa, the greater part of Africa’s territory lies north of the Equator. Africa is crossed from north to south by the prime meridian (0° longitude), which passes a short distance to the east of Accra, Ghana.
Mount Kenya in Mount Kenya National Park is the highest mountain in Africa. UNESCO World Heritage Site. Giant Lobelia in foreground. (Mt. Kenya; Mt. Kenya National Park; mountains; rugged mountain; African geography, African landscape, stratovolcano)
BRITANNICA QUIZ
Africa’s Physical Features
Can you identify the location of some of Africa’s noted physical features? Match the feature to the country it’s found in.
In antiquity the Greeks are said to have called the continent Libya and the Romans to have called it Africa, perhaps from the Latin aprica (“sunny”) or the Greek aphrike (“without cold”). The name Africa, however, was chiefly applied to the northern coast of the continent, which was, in effect, regarded as a southern extension of Europe. The Romans, who for a time ruled the North African coast, are also said to have called the area south of their settlements Afriga, or the Land of the Afrigs—the name of a Berber community south of Carthage.
The whole of Africa can be considered as a vast plateau rising steeply from narrow coastal strips and consisting of ancient crystalline rocks. The plateau’s surface is higher in the southeast and tilts downward toward the northeast. In general the plateau may be divided into a southeastern portion and a northwestern portion. The northwestern part, which includes the Sahara (desert) and that part of North Africa known as the Maghrib, has two mountainous regions—the Atlas Mountains in northwestern Africa, which are believed to be part of a system that extends into southern Europe, and the Ahaggar (Hoggar) Mountains in the Sahara. The southeastern part of the plateau includes the Ethiopian Plateau, the East African Plateau, and—in eastern South Africa, where the plateau edge falls downward in a scarp—the Drakensberg range. One of the most remarkable features in the geologic structure of Africa is the East African Rift System, which lies between 30° and 40° E. The rift itself begins northeast of the continent’s limits and extends southward from the Eritrean Red Sea coast to the Zambezi River basin.
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Africa contains an enormous wealth of mineral resources, including some of the world’s largest reserves of fossil fuels, metallic ores, and gems and precious metals. This richness is matched by a great diversity of biological resources that includes the intensely lush equatorial rainforests of Central Africa and the world-famous populations of wildlife of the eastern and southern portions of the continent. Although agriculture (primarily subsistence) still dominates the economies of many African countries, the exploitation of these resources became the most significant economic activity in Africa in the 20th century.
Climatic and other factors have exerted considerable influence on the patterns of human settlement in Africa. While some areas appear to have been inhabited more or less continuously since the dawn of humanity, enormous regions—notably the desert areas of northern and southwestern Africa—have been largely unoccupied for prolonged periods of time. Thus, although Africa is the second largest continent, it contains only about 10 percent of the world’s population and can be said to be underpopulated. The greater part of the continent has long been inhabited by Black peoples, but in historic times there also have occurred major immigrations from both Asia and Europe. Of all foreign settlements in Africa, that of the Arabs has made the greatest impact. The Islamic religion, which the Arabs carried with them, spread from North Africa into many areas south of the Sahara, so that many western African peoples are now largely Islamized.
This article treats the physical and human geography of Africa, followed by discussion of geographic features of special interest. For discussion of individual countries of the continent, see such articles as Egypt, Madagascar, and Sudan. African regions are treated under the titles Central Africa, eastern Africa, North Africa, Southern Africa, and western Africa; these articles also contain the principal treatment of African historical and cultural development. For discussion of major cities of the continent, see such articles as Alexandria, Cairo, Cape Town, Johannesburg, and Kinshasa. Related topics are discussed in the articles literature, African; literature, South African; architecture, African; art, African; dance, African; music, African; theatre, African; art and architecture, Egyptian; Islam; arts, Islamic; and Islamic world.
Davidson S.H.W. Nicol
The Editors of Encyclopaedia Britannica
Geologic history
General considerations
Ruwenzori Range
Ruwenzori Range
The African continent essentially consists of five ancient Precambrian cratons—Kaapvaal, Zimbabwe, Tanzania, Congo, and West African—that were formed between about 3.6 and 2 billion years ago and that basically have been tectonically stable since that time; those cratons are bounded by younger fold belts formed between 2 billion and 300 million years ago. All of those rocks have been extensively folded and metamorphosed (that is, they have been modified in composition and structure by heat and pressure). Precambrian rock outcrops appear on some 57 percent of the continent’s surface, while the rest of the surface consists of largely undeformed younger sediments and volcanic rocks.
The oldest rocks are of Archean age (i.e., about 4.6 to 2.5 billion years old) and are found in the so-called granite-gneiss-greenstone terrains of the Kaapvaal, Zimbabwe, and Congo cratons. They consist of gray, banded gneisses, various granitoids, and rather well-preserved volcanic rocks that show evidence of submarine extrusion (i.e., emission of rock material in molten form) and formation under high temperatures. The rock type komatiite is particularly diagnostic of those volcanic sequences and is almost exclusively restricted to the Archean Eon. The cratons were tectonically stabilized by voluminous granite intrusions toward the end of the Archean and were then covered by clastic sediments, some of which contain economically important gold and uranium deposits (e.g., the Witwatersrand System in South Africa).
The Proterozoic Eon (2.5 billion to about 541 million years ago) is characterized by the formation of several mobile belts, which are long, narrow zones of strongly deformed and metamorphosed rocks that occur between the cratons and probably resulted from the collision between the cratons due to plate tectonic processes. The oldest mobile belts are found in Archean rocks, such as the Limpopo belt separating the Kaapvaal from the Zimbabwe craton. Younger belts were formed during a continentwide thermotectonic event known as the Eburnian (2.2 to 1.8 billion years ago), which gave rise to the Birimian assemblage in western Africa, the Ubendian assemblage in east-central Africa, and large volumes of rocks in Angola. Still younger belts of the Kibaran thermotectonic event (1.2 billion to 950 million years ago) are found in eastern and Southern Africa.
The end of the Precambrian was marked by a major event of mobile-belt formation known as the Pan-African episode (about 950 to 550 million years ago), which generated long fold belts, such as the Mozambique belt along the east coast of Africa, the Damara and Katanga belts extending from Namibia into the Democratic Republic of the Congo and Zambia, the West Congo belt between Angola and Gabon, the Dahomey-Ahaggar belt between Ghana and Algeria, and the Mauritanide belt from Senegal to Morocco.
A unique late Precambrian evolution is recorded in the so-called Arabian-Nubian Shield of northeastern Africa and Arabia. There, large volumes of volcanic and granitoid rocks were generated in an island-arc, marginal-basin setting—an environment similar to that of the present southwestern Pacific Ocean. Rocks were accreted onto the ancient African continent, the margin of which was then near the present Nile River, by subduction processes identical to those observed today. (Subduction involves the descent of the edge of one lithospheric plate beneath that of another where two such plates collide.)
The interiors of the ancient cratons were not affected by the above tectonic events, and intracratonic sedimentary and volcanic sequences accumulated in large basins. The most important of those are the Transvaal basin on the Kaapvaal craton that contains economically important iron ore deposits; the Congo basin; and the West African basin, with its thick late Proterozoic sediments including a prominent tillite horizon that marks a major glaciation event at the end of the Precambrian.
Little Karoo
Little Karoo
After the Precambrian, Africa’s geologic history is characterized by the following events: the formation of fold belts in the Paleozoic Era (about 541 to 252 million years ago) in South Africa (the Cape fold belt), Morocco (the Anti-Atlas belt), and Mauritania (the Mauritanide belt) bordering the older cratons; voluminous basaltic volcanism some 230 to 200 million years ago in South Africa, Namibia, and East Africa, known as the Karoo System, that was probably related to the beginning of the breakup of the Gondwana supercontinent; the formation of a young mountain belt in northwestern Africa some 100 to 40 million years ago as a result of collision between the African and European plates, together with the closure of the ancestral Mediterranean Sea (the Tethys Sea); and the development of the East African Rift System during the Cenozoic Era (i.e., roughly the past 66 million years), leading to the opening of the Red Sea, the northeast drift of the Arabian Plate, and the fracturing of the ancient crust of Africa along several long rift valleys, accompanied by extensive volcanism.
Rock types and structural evolution
The Precambrian
The oldest rocks consist of gneisses, granites, metasediments, and metavolcanic rocks 3.6 to 2.5 billion years old; all are variably deformed and metamorphosed to some degree. The best-preserved assemblages occur in the Kaapvaal and Zimbabwe cratons and contain large deposits of gold and sulfide minerals. The volcanic suites are dominated by basaltic and komatiitic lavas, often interlayered with metasediments and generally referred to as greenstone belts. Those structures are often found together with layered gneisses, or they are intruded by granitoid plutons. Several generations of greenstones have been recognized. The oldest formed about 3.4 billion years ago, the second some 3 to 2.9 billion years ago, and the third some 2.7 to 2.6 billion years ago. Some of the oldest traces of life are preserved as unicellular algae in Precambrian cherts of the Barberton greenstone belt in the Transvaal region of South Africa. The end of the Archean is marked by voluminous granite intrusions, after which Africa’s cratons became tectonically stable. One of the most spectacular features marking the end of the Archean is the intrusion of the Great Dyke in Zimbabwe, a large, layered body of mafic-ultramafic rocks with substantial deposits of chromium, asbestos, and nickel. It is still not clear whether Archean evolution was characterized by the same plate tectonic processes that are seen today, and there are suggestions that the greenstone belts are remnants of ancient oceanic crust. Cratonic (essentially undeformed) sediments appear in the stratigraphic record for the first time in the late Archean and are best developed in the Kaapvaal craton of Southern Africa.
The early Proterozoic (about 2.5 to 1.6 billion years ago) is characterized by cratonic clastic sediments on the stable cratons—the best examples are the Witwatersrand-Ventersdorp-Transvaal basin of Southern Africa and the Francevillian basin in Gabon—and by metavolcanic-metasedimentary rocks and granitoids in noncratonic areas such as the extensive Birimian terrain of western Africa extending from Senegal to Ghana. Of particular interest are extensive stromatolite-bearing limestones and economically important iron formations in the Transvaal sequence of South Africa that provide evidence for an oxygen-rich atmosphere by about 2.2 billion years ago. About 2 billion years ago the Bushveld Complex—which is one of the largest differentiated igneous bodies on Earth, containing major deposits of platinum, chromium, and vanadium—was emplaced in the northern Kaapvaal craton. The middle part of the early Proterozoic was dominated by powerful orogenic (mountain-building) processes that gave rise to fold belts in which sedimentary and volcanic rocks originally deposited in deep basins along the continental margins were severely deformed, metamorphosed, intruded by granitoid plutons, and finally uplifted into mountain ranges, probably as a result of continental collision. That Eburnian event was particularly active in western Africa, where it deformed the Birimian assemblages; but it was also active in eastern Africa, where it generated the Ubendian belt in southern Tanzania, and in southwestern Africa, where it formed major rock units in Angola and northern Namibia. By the end of the early Proterozoic, the Archean crustal blocks had grown into cratons of considerable size.
The record of the middle Proterozoic (about 1.6 to 1 billion years ago) shows deposition of continental sediments and volcanic rocks on the cratons and adjacent to the earlier fold belts (molasse deposits). Undeformed or only mildly folded successions are found in Southern Africa (Waterberg and Matsap sequences), in northern Zambia, and in the Democratic Republic of the Congo. Elsewhere, sedimentary and volcanic sequences were deposited in elongate basins that were later subjected to intense deformation and metamorphism during the Kibaran event. That important thermotectonic episode gave rise to the Kibaran-Burundian fold belt in east-central Africa, the Ruwenzori belt in Uganda, and the Namaqua-Natal belt in South Africa and Namibia.
The late Proterozoic (about 1 billion to 541 million years ago) is again characterized by platform deposits in stable areas, such as the West African craton (Taoudeni and Tindouf basins), the Congo craton, the Kalahari craton (Nama basin of Namibia), and the Tanzania craton (Bukoban beds). Tectonic and magmatic activity was concentrated in mobile belts surrounding the stable areas and took place throughout the late Proterozoic, during the so-called Pan-African thermotectonic event. Long, linear belts—such as the Damara-Katanga of central and southwestern Africa, the Mozambique belt of eastern Africa, and the Dahomey-Ahaggar belt of western Africa—formed during that time, and some of those belts contain diagnostic rock assemblages that indicate that they resulted from continental collisions. Many late Precambrian sequences of Africa contain one or two beds of tillites (sedimentary rocks that are composed of lithified clay and rock sediments produced by the action of ice), which are thought to have resulted from an extensive glaciation that covered much of Africa at that time. In the Arabian (Eastern) Desert of Egypt and in the Red Sea Hills of Sudan, a predominance of volcanic rocks and granitoids, together with frequent remnants of ancient oceanic crust, document an evolution similar to what is now occurring in the island-arc systems of the southwestern Pacific. Those rocks clearly demonstrate that plate tectonic processes operated in the late Precambrian.
The Paleozoic Era
Table Mountain
Table Mountain
The Paleozoic Era consists of the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian periods and includes two major mountain-building episodes. The continent of Africa may be said to have taken shape during the Paleozoic. A glacial period during the Ordovician is evidenced by widespread deposition tillites, which may be seen in southern Morocco, throughout western Africa, and in subequatorial Africa as far south as Namibia. That tillite sequence marks the transition from the end of the Precambrian to the beginning of the Cambrian Period.
Marine fossils of the Cambrian Period (about 541 to 485 million years ago) are found in southern Morocco, the Western and Mauritanian Sahara, and Namibia. In Egypt and in the Arabian Peninsula their presence has been revealed by drilling. Elsewhere they remain unknown.
During the Ordovician Period (about 485 to 444 million years ago), fossiliferous marine sandstone completely covered northern and western Africa, including the Sahara. The Table Mountain sandstone of South Africa constitutes its only other trace. That period is, in addition, remarkable for broad, large-scale deformation of the African crust, which raised the continental table of the central and western Sahara by approximately 5,000 feet (1,500 metres). Each emergence resulted in the creation of valleys that became flooded when the continent subsided. Toward the end of the period, the Sahara became glaciated, and tillites and sandstones filled the valleys. A complete change of sedimentation characterized the Silurian Period (about 444 to 419 million years ago), which is indicated by the deposits of graptolitic shales (those containing small fossil colonies of extinct marine animals of uncertain zoological affinity) in the Arabian Peninsula and in northwestern Africa.
Marine fossils of the Devonian Period (about 419 to 359 million years ago) are found in North Africa and in the Sahara. Traces also have been discovered in parts of Guinea, Ghana, and Arabia, as well as in Gabon; they also occur in the Bokkeveld Series of South Africa. Fossilized plants that include Archaeosigillaria (ancient club mosses) may be traced in formations of the earlier Devonian Period in the Sahara and in South Africa (Witteberg Series).
Mount Kenya in Mount Kenya National Park is the highest mountain in Africa. UNESCO World Heritage Site. Giant Lobelia in foreground. (Mt. Kenya; Mt. Kenya National Park; mountains; rugged mountain; African geography, African landscape, stratovolcano)
BRITANNICA QUIZ
Africa’s Physical Features
Can you identify the location of some of Africa’s noted physical features? Match the feature to the country it’s found in.
The Carboniferous Period (about 359 to 299 million years ago) was marked by the onset of several major tectonic events. Evidence of marine life that existed in the earlier part of the period comes from fossils found in North Africa, the central and western Sahara, and Egypt. During the middle and later parts of the Carboniferous, the Hercynian mountain-building episodes occurred as a result of collision between the North American and African plates. The Mauritanide mountain chain was compressed and folded at that time along the western margin of the West African craton from Morocco to Senegal. Elsewhere, major uplift or subsidence occurred, continuing until the end of the Triassic Period (i.e., about 201 million years ago). Those structures were synformal (folded with the strata dipping inward toward a central axis) in the Tindouf and Taoudeni basins of western Algeria, Mauritania, and Mali and antiformal (forming a mountainous spine or dome) at Reguibat in eastern Western Sahara.
The late Carboniferous Period is represented throughout the Sahara by layers of fossilized plants and sometimes—as in Morocco and Algeria—by seams of coal. Different phenomena may be observed, however, in the region of subequatorial Africa, including the Dwyka tillite, which covers part of South Africa, Namibia, Madagascar, an extensive portion of the Congo Basin, and Gabon. At several places in South Africa, the Dwyka strata are covered by thin marine layers that serve to demarcate the transition from the Carboniferous to the Permian Period and that form the beginning of the great Karoo System.
Marine fossils of the Permian Period (about 299 to 252 million years ago) are visible in southern Tunisia, in Egypt, in the Arabian Peninsula, on the coasts of Tanzania, and in the Mozambique Channel. Elsewhere, traces of the Permian are of continental rather than marine origin and are included in the Karoo System in South Africa. There, the lower Permian strata are known as the Ecca Series and are divided into three groups: the Lower Ecca (containing almost 1,000 feet [300 metres] of shales), the Middle Ecca (some 1,650 feet [500 metres] of sandstone, seams of coal, and fossilized plants), and the Upper Ecca (about 650 feet [200 metres] of shales again).
The upper Permian is represented by the lower part of the Beaufort Series, which continued forming into the early Triassic Period. The Beaufort Series is almost 10,000 feet (3,000 metres) thick and is famous for its amphibian and reptile fossils; a similar series is also found in southern Russia. Other Permian formations, not as rich in coal, occur in the Democratic Republic of the Congo, Tanzania, Kenya, Uganda, Zambia, Zimbabwe, Mozambique, and Madagascar.
The absence of primary marine formations throughout Southern Africa should be emphasized. It is not yet known whether that absence is due to a hiatus in deposition or to erosion.
The Mesozoic Era
The Mesozoic Era (about 252 to 66 million years ago) is divided into three periods—the Triassic, Jurassic, and Cretaceous—and is remarkable for the transgression of ancient seas and for the emergence of massive land formations containing interesting fossil remains.
Marine formations
During the Triassic Period (about 252 to 201 million years ago), ancient seas left deposits of marine formations in North Africa, the southern Sahara, Egypt, Arabia, and parts of Tanzania and northern Madagascar. Deposits from the Jurassic Period (about 201 to 145 million years ago) extend to the Atlantic basins of the Río de Oro region of Western Sahara and Senegal along the northwest coast of the continent. In the middle of the Jurassic a great transgression of the Indian Ocean extended over Somalia and much of Ethiopia. That event was followed by a series of marine transgressions in the Cretaceous Period (about 145 to 66 million years ago), including those along the coasts of equatorial Africa when Gondwana broke up and the present Atlantic and Indian oceans took shape; during one transgression a shallow sea covered much of the northern and central Sahara and Egypt as far south as Sudan; and a later one again covered the same areas, as well as western Arabia and the west coast of Madagascar.
Continental formations
In Africa north of the Equator and in Arabia, Mesozoic continental formations covered large areas. During the Triassic the Saharan Zarz
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