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32-633: The name of the province derives from that of the Cuando and Cubango rivers, which flow through the eastern and western edges of the province, respectively. Throughout much of the 1980s and 1990s, Cuando Cubango served as the location for the primary base camp of Angola's UNITA rebel movement, led by Jonas Savimbi . The rebel movement received support from the United States as part of the Cold War conflict against Angola's Marxist government, which

64-791: A water gap may occur. In these, erosion from a stream occurs faster than mountain uplift, resulting in a gorge or valley that runs through a mountain range from low-lying country on one side to similar country on the other. Examples of such water gaps include the Manawatū Gorge in New Zealand and the Cumberland Narrows in Maryland . The removal of mass from a region will be isostatically compensated by crustal rebound. If we take into consideration typical crustal and mantle densities, erosion of an average 100 meters of rock across

96-464: A broad, uniform surface will cause the crust to isostatically rebound about 85 meters and will cause only a 15-meter loss of mean surface elevation. An example of isostatic uplift is post-glacial rebound following the melting of ice sheets . The Hudson Bay region of Canada, the Great Lakes of Canada and the United States, and Fennoscandia are currently undergoing gradual rebound as a result of

128-508: A more modest uplift over a large region. Perhaps the most extreme form of orogenic uplift is a continental-continental crustal collision. In this process, two continents are sutured together, and large mountain ranges are produced. The collision of the Indian and Eurasian plates is a good example of the extent to which orogenic uplift can reach. Heavy thrust faulting (of the Indian plate beneath

160-463: A relatively small role, and high peak formation can be more attributed to tectonic processes. Direct measures of the elevation change of the land surface can only be used to estimate erosion or bedrock uplift rates when other controls (such as changes in mean surface elevation, volume of eroded material, timescales and lags of isostatic response, variations in crustal density) are known. In a few cases, tectonic uplift can be seen in coral islands . This

192-776: A seasonal lake, Lake Liambesi (map, 7), it is called the Chobe (map, 8). The river then flows into the Zambezi just above the former Kazungula Ferry (map, 9), now replaced by the Kazungula Bridge . In years when the Okavango experiences a good flood some of the water escapes east along the normally dry channel of the Magwekwana River (also known as Selinda Spillway) into the Linyanti Swamp, thus entering

224-482: Is an upper limit to vertical mountain growth). Although the raised surfaces of mountain ranges mainly result from crustal thickening, there are other forces at play that are responsible for the tectonic activity. All tectonic processes are driven by gravitational force when density differences are present. A good example of this would be the large-scale circulation of the Earth's mantle . Lateral density variations near

256-679: Is evidenced by the presence of various oceanic islands composed entirely of coral , which otherwise appear to be volcanic islands . Examples of such islands are found in the Pacific, notably the three phosphate islets of Nauru , Makatea , and Banaba , as well as Maré and Lifou in New Caledonia ; Fatu Huku in the Marquesas Islands ; and Henderson Island in the Pitcairn Islands . The uplift of these islands

288-452: Is known to be sensitive to temperature and rainfall. The magnitude of the exhumation a rock has been subjected to may be inferred from geothermobarometry (measuring previous pressure and temperature history of a rock or assemblage). Knowing the pressure and temperature history of a region can yield an estimate of the ambient geothermal gradient and bounds on the exhumation process; however, geobarometric/geothermometric studies do not produce

320-404: Is proportional to the rate of increase of average surface height. The highest rates of working against gravity are required when the thickness of the crust (not the lithosphere) changes. Lithospheric flexure is the process by which the lithosphere bends under the action of forces such as the weight of a growing orogeny or changes in ice thickness related to glaciation. The lithosphere rests on

352-450: Is specified. Molnar and England identify three kinds of displacement to which the term "uplift" is applied: This simple equation relates the three kinds of displacement: The term geoid is used above to mean mean sea level and makes a good frame of reference. A given displacement within this frame of reference allows one to quantify the amount of work being done against gravity. Measuring uplift and exhumation can be tricky. Measuring

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384-409: Is the result of the movement of oceanic tectonic plates. Sunken islands or guyots with their coral reefs are the result of crustal subsidence as the oceanic plate carries the islands to deeper or lower oceanic crust areas. The word "uplift" refers to displacement contrary to the direction of the gravity vector, and displacement is only defined when the object being displaced and the frame of reference

416-511: The Zambian border. Along this reach it flows in a maze of channels in a swampy corridor 5–10 km wide (map 1: the border with Zambia is the eastern bank of this floodplain, not the river channel). As with all rivers in south-central Africa, its flow varies enormously between the rainy season when it floods and may be several kilometres wide, and the dry season when it may disappear into marshes. The Cuando continues in its marshy channel across

448-487: The asthenosphere , a viscous layer that in geological time scales behaves like a fluid. Thus, when loaded, the lithosphere progressively reaches an isostatic equilibrium. For example, the lithosphere on the oceanward side of an oceanic trench at a subduction zone will curve upwards due to the elastic properties of the Earth's crust. Orogenic uplift is the result of tectonic-plate collisions and results in mountain ranges or

480-524: The Eurasian plate) and folding are responsible for the suturing together of the two plates. The collision of the Indian and Eurasian plates produced the Himalayas and is also responsible for crustal thickening north into Siberia . The Pamir Mountains , Tian Shan , Altai , Hindu Kush , and other mountain belts are all examples of mountain ranges formed in response to the collision of the Indian with

512-815: The Eurasian plate. The Ozark Plateau is a broad uplifted area which resulted from the Permian Ouachita Orogeny to the south in the states of Arkansas , Oklahoma , and Texas . Another related uplift is the Llano Uplift in Texas, a geographical location named after its uplift features. The Colorado Plateau which includes the Grand Canyon is the result of broad tectonic uplift followed by river erosion . When mountains rise slowly, either due to orogenic uplift or other processes (e.g., rebound after glaciation ), an unusual feature known as

544-664: The Linyanti Swamp) dotted with alluvial islands, nearly disappearing into the Kalahari sands like the Okavango (map, 5). But instead it has diverted east and has been captured by the Zambezi. The flow turns sharply east, still forming the border with Botswana . In the dry season there are few open channels through the swamps and marshes. Beginning at this point it is known as the Linyanti (map, 6), and after it flows through

576-757: The Zambezi basin. The Selinda Spillway and the Boteti River are the only outlets of the Okavango basin . On the north side of the Chobe River are the Caprivi Swamps, on the edge of which is the ruined capital of the Kololo people who conquered Barotseland in the 19th century. So much of the water of the Cuando, Linyanti and Chobe is lost to evaporation in the various swamps that its contribution to

608-460: The chance of returning to their former state. The national parks through which it passes or on which it borders are: Tectonic uplift Tectonic uplift is the geologic uplift of Earth's surface that is attributed to plate tectonics . While isostatic response is important, an increase in the mean elevation of a region can only occur in response to tectonic processes of crustal thickening (such as mountain building events), changes in

640-410: The density distribution of the crust and underlying mantle , and flexural support due to the bending of rigid lithosphere . Tectonic uplift results in denudation (processes that wear away the earth's surface) by raising buried rocks closer to the surface. This process can redistribute large loads from an elevated region to a topographically lower area as well – thus promoting an isostatic response in

672-775: The flow of the Zambezi is very small except in occasional years when it floods excessively. The perennial river bifurcation of Selinda Spillway (or Magweggana River), on the Cuando River, connects the Kalahari Basin to the Zambezi Basin . The Cuando system is noted for its wildlife and for most of its length the land either side is protected as game reserves or wildlife management areas. Some of these suffered poaching during wars and conflict in Namibia and Angola, but with peace restored in those countries they have

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704-451: The melting of ice sheets 10,000 years ago. Crustal thickening, which for example is currently occurring in the Himalayas due to the continental collision between the Indian and the Eurasian plates, can also lead to surface uplift; but due to the isostatic sinking of thickened crust, the magnitude of surface uplift will only be about one-sixth of the amount of crustal thickening. Therefore, in most convergent boundaries , isostatic uplift plays

736-545: The most prominent conflicts of the Cold War, with both the United States and the Soviet Union depicting its outcome as important to the global balance of power. Cuando Cubango is traversed by the northwesterly line of equal latitude and longitude. It is located in the extreme south-east of Angola. To the north and north-east it is bordered with Moxico Province , and in the west - the provinces of Huila and Cunene . In

768-587: The neck of the Caprivi Strip of Namibia (map, 2) and then forms the border between Namibia and Botswana as it continues southeast. Some 10,000 years ago, the Cuando merged with the Okavango River and they flowed south to Lake Makgadikgadi (which is a seasonal wetland in current times ), but the land in that area was uplifted . As a consequence the Cuando now meets slightly higher ground (map, 4) and breaks up into many channels and swamps (called

800-626: The non-colonial spelling) is a river in south-central Africa flowing through Angola and Namibia's Caprivi Strip and into the Linyanti Swamp on the northern border of Botswana . Below the swamp, the river is called the Linyanti River and, farther east, the Chobe River , before it flows into the Zambezi River . The Cuando rises in the central plateau of Angola on the slopes of Mount Tembo , thence flowing southeast along

832-559: The other; evidence of this process can be seen in preserved ophiolitic nappes (preserved in the Himalayas ) and in rocks with an inverted metamorphic gradient . The preserved inverted metamorphic gradient indicates that nappes were actually stacked on top of each other so quickly that hot rocks did not have time to equilibrate before being thrust on top of cool rocks. The process of nappe stacking can only continue for so long, as gravity will eventually disallow further vertical growth (there

864-547: The period 1965 to 1991 during the foreign intervention years of the Angolan Civil War . In particular, the area was previously suitable habitat for the endangered painted hunting dog , Lycaon pictus , which is now deemed extirpated in the local area. Up to 1991, the official name was Provincial Commissioner 16°5′S 19°30′E  /  16.083°S 19.500°E  / -16.083; 19.500 Cuando River The Cuando River (or Kwando in

896-404: The region of denudation (which can cause local bedrock uplift). The timing, magnitude, and rate of denudation can be estimated by geologists using pressure-temperature studies. Crustal thickening has an upward component of motion and often occurs when continental crust is thrust onto continental crust. Basically nappes (thrust sheets) from each plate collide and begin to stack one on top of

928-438: The south of Cuando Cubango it borders Namibia , and to the east - Zambia . The province of Cuando Cubango contains nine municipalities ( Portuguese : municípios ): The province of Cuando Cubango contains the following communes ( Portuguese : comunas ); sorted by their respective municipalities: Considerable natural habitat previously existed within the province, although much of these areas has been destroyed during

960-417: The surface (such as the creation, cooling, and subduction of oceanic plates ) also drive plate motion. The dynamics of mountain ranges are governed by differences in the gravitational energy of entire columns of the lithosphere (see isostasy ). If a change in surface height represents an isostatically compensated change in crustal thickness, the rate of change of potential energy per unit surface area

992-690: The uplift of a point requires measuring its elevation change – usually geoscientists are not trying to determine the uplift of a singular point but rather the uplift over a specified area. Accordingly, the change in elevation of all points on the surface of that area must be measured, and the rate of erosion must be zero or minimal. Also, sequences of rocks deposited during that uplift must be preserved. Needless to say, in mountain ranges where elevations are far above sea level these criteria are not easily met. Paleoclimatic restorations though can be valuable; these studies involve inferring changes in climate in an area of interest from changes with time of flora/fauna that

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1024-539: Was supported by the Soviet Union , Cuba and other communist states. Savimbi and UNITA maintained a large and clandestine base camp in the Cubando Cubango town of Jamba . The camp was protected by anti-aircraft weapons and included an air strip, which was used for the delivery of military and other supplies, which typically arrived from neighboring Zaire . The Angolan Civil War ultimately became one of

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