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South Africa Physical Setting
South Africa occupies the southern tip of the African continent, stretching from 22°S to 35°S latitude and from 17°E to 33°E longitude. The northeastern corner of the country lies within the tropics, astride the Tropic of Capricorn. So
uth Africa covers 1.2 million square kilometers of land, one-seventh the area of the United States, or roughly twice the area of Texas. Nearly 4,900 kilometers of international boundaries separate South Africa from Namibia, Botswana, Zimbabwe, Mozambique,
and Swaziland--from northwest to northeast--and South Africa completely surrounds the small nation of Lesotho. In addition, the 2,881-kilometer coastline borders the Atlantic Ocean on the west and the Indian Ocean on the south and east. South Africa's ex
traterritorial holdings include Robben Island, Dassen Island, and Bird Island in the Atlantic Ocean, and Prince Edward Island and Marion Island about 1,920 kilometers southeast of Cape Town in the Indian Ocean. Marion Island, at 46°S latitude, is the
site of an important weather research station.
South Africa forms a distinct region, or subcontinent, divided from the rest of Africa by the rivers that mark its northern border. In the northwest, the Orange River cuts through the Namib Desert and divides South Africa from Namibia. In the east, th
e Limpopo River traverses large areas of arid grassland along the common border with Zimbabwe and southeastern Botswana. Between these two, the Molopo River winds through the southern basin of the Kalahari Desert, also dividing South Africa from Botswana.
Populations have moved across these rivers almost continuously over the centuries, but, in general, the northern border region of South Africa is sparsely populated.
The geological substratum of the subcontinent was formed at least 3.8 billion years ago, according to geologists, and most of the country's natural features evolved into their present form more than 200 million years ago. Especially since the early tw
entieth-century writings of Alfred Wegener, geologists have hypothesized that South Africa was once part of a large land mass, now known as Gondwana, or Gondwanaland, that slowly fractured along the African coastline millions of years ago. Theories of suc
h a supercontinent are bolstered by geological continuities and mineral similarities between South Africa and South America, by fossil similarities between South Africa and the Indian Ocean island of Madagascar, and by the sharp escarpments, or geological
fractures, that encircle most of southern Africa near the coast.
The ancient rock substratum is overlain by sedimentary and volcanic rock formations. Because ground cover is sparse, only about 11 percent of the land in South Africa is arable. More than 20 percent of the land is too arid or the soil is too poor for
any agricultural activity without irrigation; roughly 66 percent is suitable only for livestock grazing. Even the thin soil cover has been severely eroded, especially in the country's most overpopulated and impoverished rural areas. The relatively poor la
nd conceals enormous wealth in minerals, however, including gold, diamonds, copper, platinum, asbestos, and coal.
Geographic Regions
Like much of the African continent, South Africa's landscape is dominated by a high plateau in the interior, surrounded by a narrow strip of coastal lowlands. Unlike most of Africa, however, the perimeter of South Africa's inland plateau rises abruptl
y to form a series of mountain ranges before dropping to sea level. These mountains, known as the Great Escarpment, vary between 2,000 meters and 3,300 meters in elevation. The coastline is fairly regular and has few natural harbors. Each of the dominant
land features--the inland plateau, the encircling mountain ranges, and the coastal lowlands--exhibits a wide range of variation in topography and in natural resources (see fig. 7).
The interior plateau consists of a series of rolling grasslands ("veld," in Afrikaans), arising out of the Kalahari Desert in the north. The largest subregion in the plateau is the 1,200-meter to 1,800-meter-high central area known as the Highveld. Th
e Highveld stretches from Western Cape province to the northeast, encompassing the entire Free State (formerly, Orange Free State). In the north, it rises into a series of rock formations known as the Witwatersrand (literally, "Ridge of White Waters" in A
frikaans, commonly shortened to Rand--see Glossary). The Rand is a ridge of gold-bearing rock, roughly 100 kilometers by thirty-seven kilometers, that serves as a watershed for numerous rivers and streams. It is also the site of the world's largest proven
gold deposits and the country's leading industrial city, Johannesburg.
North of the Witwatersrand is a dry savanna subregion, known as the Bushveld, characterized by open grasslands with scattered trees and bushes. Elevation varies between 600 meters and about 900 meters above sea level. The Bushveld, like the Rand, hous
es a virtual treasure chest of minerals, one of the largest and best known layered igneous (volcanic) mineral complexes in the world. Covering an area roughly 350 kilometers by 150 kilometers, the Bushveld has extensive deposits of platinum and chromium a
nd significant reserves of copper, fluorspar, gold, nickel, and iron.
Along the northern edge of the Bushveld, the plains rise to a series of high plateaus and low mountain ranges, which form the southern edge of the Limpopo River Valley in Northern Province. These mountains include the Waterberg and the Strypoortberg r
anges, and, in the far north, the Soutpansberg Mountains. The Soutpansberg range reaches an elevation of 1,700 meters before dropping off into the Limpopo River Valley and the border between South Africa and Zimbabwe. The Kruger National Park, which is kn
own for its diverse terrain and wildlife, abuts most of the north-south border with Mozambique.
West of the Bushveld is the southern basin of the Kalahari Desert, which borders Namibia and Botswana at an elevation of 600 meters to 900 meters. Farther south, the Southern Namib Desert stretches south from Namibia along the Atlantic coastline. Betw
een these two deserts lies the Cape Middleveld subregion, an arid expanse of undulating plains that sometimes reaches an elevation of 900 meters. The Cape Middleveld is also characterized by large depressions, or "pans," where rainfall collects, providing
sustenance for a variety of plants and animals.
The southern border of the Highveld rises to form the Great Escarpment, the semicircle of mountain ranges roughly paralleling South Africa's coastline. The Drakensberg Mountains, the country's largest mountain range, dominate the southern and the eas
tern border of the Highveld from the Eastern Cape province to the border with Swaziland. The highest peaks of the Drakensberg Mountains in KwaZulu-Natal exceed 3,300 meters and are even higher in Lesotho, which is known as the "Mountain Kingdom."
In the west and the southwest, the Cape Ranges, the country's only "fold mountains"--formed by the folding of the continental crust--form an "L," where the north-south ranges meet several east-west ranges. The north-south Cape Ranges, paralleling the
Atlantic coastline, include the Cedarberg Mountains, the Witsenberg Mountains, and the Great Winterhoek Mountains, and have peaks close to 2,000 meters high. The east-west ranges, paralleling the southern coastline, include the Swartberg Mountains and the
Langeberg Mountains, with peaks exceeding 2,200 meters.
The Cape Ranges are separated from the Highveld by a narrow strip of semidesert, known as the Great Karoo (Karoo is a Khoisan term for "land of thirst"). Lying between 450 meters and 750 meters above sea level, the Great Karoo is crossed by several ri
vers that have carved canyons and valleys in their southward descent from the Highveld into the ocean. Another narrow strip of arid savanna lies south of the Great Karoo, between the Swartberg Mountains and the Langeberg Mountains. This high plain, known
as the Little Karoo, has a more temperate climate and more diverse flora and fauna than the Great Karoo.
The narrow coastal strip between the Great Escarpment and the ocean, called the Lowveld, varies in width from about sixty kilometers to more than 200 kilometers. Beyond the coastline, the continental shelf is narrow in the west but widens along the so
uth coast, where exploitable deposits of oil and natural gas have been found. The south coast is also an important spawning ground for many species of fish that eventually migrate to the Atlantic Ocean fishing zones.
Data as of May 1996
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