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Transvaal Basin
The Transvaal Basin is one of three basins of the Transvaal Supergroup on the Kaapvaal craton. The evolution of this 2.65–2.05 Ga Neoarchaean– Palaeoproterozoic basin is thought to have been derived largely from magmatism, palaeoclimate and eustasy, while plate tectonics played an intermittent role. The supergroup is made up of basal ‘ protobasinal’ rocks, upon which followed the Black Reef Formation, Chuniespoort Group and the uppermost Pretoria Group. The Transvaal Supergroup displays three unconformity-bounded sequences that surface in two geographically distinct areas – the Transvaal Basin, which circumscribes the Bushveld Igneous Complex, and the Griqualand West basin, lying between Kimberley and Sishen at the western Kaapvaal craton rim, extending into southern Botswana beneath the Kalahari Sands as the Kanye Basin. The two basins are separated by the broad Vryburg Arch. Between approximately 2.640 and 2.516  Ga, two successive stromatolitic c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
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) including adjacent islands, it covers 6% of Earth's total surface area and 20% of its land area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With billion people as of , it accounts for about of the world's human population. Africa's population is the youngest amongst all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Despite a wide range of natural resources, Africa is the least wealthy continent per capita and second-least wealthy by total wealth, behind Oceania. Scholars have attributed this to different factors including geography, climate, tribalism, Scramble for Africa, colonialism, the Cold War, neocolonialism, lack of democracy, and corruption. Despite this low concentration of wealth, recent economic expansion and the large and young ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chuniespoort Group
Chuniespoort (recently Chuenespoort) is a mountain pass situated in the Limpopo Province, on the R37, the road between Polokwane and Lebowakgomo, South Africa. The river flowing through this gorge of the Strydpoort Mountains is known as the Chunies River, one of the tributaries of the Olifants River. Etymology The pass is named for an African leader, whose name would be spelled ''Tshwene'' in modern Northern Sotho orthography An orthography is a set of conventions for writing a language, including norms of spelling, hyphenation, capitalization, word breaks, emphasis, and punctuation. Most transnational languages in the modern period have a writing system, and mo .... References Populated places in the Polokwane Local Municipality Mountain passes of Limpopo {{Limpopo-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tidal Flat
Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal flat ecosystems are as extensive globally as mangroves, covering at least of the Earth's surface. / They are found in sheltered areas such as bays, bayous, lagoons, and estuaries; they are also seen in freshwater lakes and salty lakes (or inland seas) alike, wherein many rivers and creeks end. Mudflats may be viewed geologically as exposed layers of bay mud, resulting from deposition of estuarine silts, clays and aquatic animal detritus. Most of the sediment within a mudflat is within the intertidal zone, and thus the flat is submerged and exposed approximately twice daily. A recent global remote sensing analysis estimated that approximately 50% of the global extent of tidal flats occurs within eight countries (Indonesia, China, Aust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonate Rock
Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major types are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO3), and dolomite rock (also known as dolostone), which is composed of mineral dolomite (CaMg(CO3)2). Calcite can be either dissolved by groundwater or precipitated by groundwater, depending on several factors including the water temperature, pH, and dissolved ion concentrations. Calcite exhibits an unusual characteristic called retrograde solubility in which it becomes less soluble in water as the temperature increases. When conditions are right for precipitation, calcite forms mineral coatings that cement the existing rock grains together or it can fill fractures. Karst topography and caves develop in carbonate rocks because of their solubility in dilute acidic groundwater. Cooling groundwater or mixing of different groundwaters will also create conditions suitable for cave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava Flow
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is also often called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. The word ''lava'' comes from Italian and is probably derived from the Latin word ''labes' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siliciclastic
Siliciclastic (or ''siliclastic'') rocks are clastic noncarbonate sedimentary rocks that are composed primarily of silicate minerals, such as quartz or clay minerals. Siliciclasic rock types include mudrock, sandstone, and conglomerate Conglomerate or conglomeration may refer to: * Conglomerate (company) * Conglomerate (geology) * Conglomerate (mathematics) In popular culture: * The Conglomerate (American group), a production crew and musical group founded by Busta Rhymes ** Co .... Siliciclastic sediments are silica-based sediments, lacking carbon compounds, which are formed from pre-existing rocks, by breakage, transportation and redeposition to form sedimentary rock.Oilfield Glossary: siliciclastic sediment. Retrieved 23 August 2018. References ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonate Platform
A carbonate platform is a sedimentary body which possesses topographic relief, and is composed of autochthonic calcareous deposits. Platform growth is mediated by sessile organisms whose skeletons build up the reef or by organisms (usually microbes) which induce carbonate precipitation through their metabolism. Therefore, carbonate platforms can not grow up everywhere: they are not present in places where limiting factors to the life of reef-building organisms exist. Such limiting factors are, among others: light, water temperature, transparency and pH-Value. For example, carbonate sedimentation along the Atlantic South American coasts takes place everywhere but at the mouth of the Amazon River, because of the intense turbidity of the water there. Spectacular examples of present-day carbonate platforms are the Bahama Banks under which the platform is roughly 8 km thick, the Yucatan Peninsula which is up to 2 km thick, the Florida platform, the platform on which the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stromatolite
Stromatolites () or stromatoliths () are layered sedimentary formations ( microbialite) that are created mainly by photosynthetic microorganisms such as cyanobacteria, sulfate-reducing bacteria, and Pseudomonadota (formerly proteobacteria). These microorganisms produce adhesive compounds that cement sand and other rocky materials to form mineral " microbial mats". In turn, these mats build up layer by layer, growing gradually over time. A stromatolite may grow to a meter or more. Although they are rare today, fossilized stromatolites provide records of ancient life on Earth. Morphology Stromatolites are layered, biochemical, accretionary structures formed in shallow water by the trapping, binding and cementation of sedimentary grains in biofilms (specifically microbial mats), through the action of certain microbial lifeforms, especially cyanobacteria. They exhibit a variety of forms and structures, or morphologies, including conical, stratiform, domal, columnar, and bran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kalahari Sands
The Kalahari Desert is a large semi-arid sandy savanna in Southern Africa extending for , covering much of Botswana, and parts of Namibia and South Africa. It is not to be confused with the Angolan, Namibian, and South African Namib coastal desert, whose name is of Khoekhoegowab origin and means "vast place". Etymology ''Kalahari'' is derived from the Tswana word ''Kgala'', meaning "the great thirst", or ''Kgalagadi'', meaning "a waterless place"; the Kalahari has vast areas covered by red sand without any permanent surface water. History The Kalahari Desert was not always a dry desert. The fossil flora and fauna from Gcwihaba Cave in Botswana indicates that the region was much wetter and cooler at least from 30 to 11 thousand BP (before present) especially after 17,500 BP. Geography Drainage of the desert is by dry black valleys, seasonally inundated pans and the large salt pans of the Makgadikgadi Pan in Botswana and Etosha Pan in Namibia. The only permanent river, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sishen
Dingleton is a town in Northern Cape, South Africa. The nearby Sishen mine is an iron ore mining activity, connected to the port of Saldanha Bay by the Sishen-Saldanha Railway Line. The line is electrified at 50 kV AC 5 (five) is a number, numeral and digit. It is the natural number, and cardinal number, following 4 and preceding 6, and is a prime number. It has attained significance throughout history in part because typical humans have five digits on eac ... and the trains using this line are amongst the heaviest trains in the world. The state-owned mining company Iscor started developing the township, originally named Sishen, in 1953 to accommodate the local miners. The houses were sold to individuals in the early 1980s. On 23 June 1990 the town's name was changed from Sishen to Dingleton. The proximity of the mining activities led to complaints from the residents of Dingleton, and expectations that the residents would be relocated. The town's infrastructure is old ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kimberley, Northern Cape
Kimberley is the Capital city, capital and largest city of the Northern Cape province of South Africa. It is located approximately 110 km east of the confluence of the Vaal River, Vaal and Orange Rivers. The city has considerable historical significance due to its diamond mining past and the Siege of Kimberley, siege during the Second Boer War, Second Anglo-Boer war. British businessmen Cecil Rhodes and Barney Barnato made their fortunes in Kimberley, and Rhodes established the De Beers diamond company in the early days of the mining town. On 2 September 1882, Kimberley was the first city in the Southern Hemisphere and the second in the world after Philadelphia, Pennsylvania in the United States of America, United States to integrate electric street lights into its infrastructure. The first stock exchange in Africa was built in Kimberley, as early as 1881. History Discovery of diamonds In 1866, Erasmus Jacobs found a small brilliant pebble on the banks of the Orange Ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Griqualand West
Griqualand West is an area of central South Africa with an area of 40,000 km2 that now forms part of the Northern Cape Province. It was inhabited by the Griqua people – a semi-nomadic, Afrikaans-speaking nation of mixed-race origin, who established several states outside the expanding frontier of the Cape Colony. It was also inhabited by the pre-existing Tswana and Khoisan peoples. In 1873 it was proclaimed as a British colony, with its capital at Kimberley, and in 1880 it was annexed by the Cape Colony. When the Union of South Africa was formed in 1910, Griqualand West was part of the Cape Province but continued to have its own "provincial" sports teams. Early history The indigenous population of the area were the Khoi-khoi and Bushmen peoples, who were hunter-gatherers or herders. Early on they were joined by the agriculturalist Batswana, who migrated into the area from the north. They comprised the majority of the population throughout the region's history, up unt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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