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Stormberg Group
The Stormberg Group is one of the four geological groups that comprises the Karoo Supergroup in South Africa. It is the uppermost geological group representing the final phase of preserved sedimentation of the Karoo Basin. The Stormberg Group rocks are considered to range between Lower Triassic (Olenekian) to Lower Jurassic ( Pliensbachian) in age. These estimates are based on means of geological dating including stratigraphic position, lithostratigraphic and biostratigraphic correlations, and palynological analyses. Background Sediment deposition of the Stormberg Group took place in a terrestrial environment that was seasonally arid. The depositional environment in the lower sections of the Stormberg was similar to that of the Katberg Formation. Both places feature coarser-grained sandstones that lack fining-upward sequences, thus pointing to an alluvial fan and braided river environment. The depositional environment changes towards the centre of the Stormberg as mudstones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Triassic
The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. The corresponding series (stratigraphy), series of rock beds is known as the Upper Triassic. The Late Triassic is divided into the Carnian, Norian and Rhaetian Geologic time scale, ages. Many of the first dinosaurs evolved during the Late Triassic, including ''Plateosaurus'', ''Coelophysis'', ''Herrerasaurus'', and ''Eoraptor''. The Triassic–Jurassic extinction event began during this epoch and is one of the five major mass extinction events of the Earth. Etymology The Triassic was named in 1834 by Friedrich August von Namoh, Friedrich von Alberti, after a succession of three distinct rock layers (Greek meaning 'triad') that are widespread in southern Germany: the lower Buntsandstein (colourful ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardap
Hardap is one of the fourteen regions of Namibia, its capital is Mariental. Hardap contains the municipality of Mariental, the towns Rehoboth and Aranos, and the self-governed villages Gibeon, Gochas, Kalkrand, Stampriet and Maltahöhe. It is home to the Hardap Dam. Geography Hardap stretches the entire width of Namibia, from the Atlantic Ocean in the west to Namibia's eastern national border. In the northeast, it borders the Kgalagadi District of Botswana, and in the southeast, it borders the Northern Cape Province of South Africa. Domestically, it borders the following regions: * Erongo – northwest * Khomas – north central *Omaheke – northeast * ǁKaras – south Politics As of 2020, Hardap had 52,534 registered voters. The region comprises eight electoral constituencies: * Gibeon * Mariental Rural * Mariental Urban * Rehoboth Rural * Rehoboth Urban East * Rehoboth Urban West * Aranos (created in 2013) * Daweb (created in 2013) As in all other reg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olenekian
In the geologic timescale, the Olenekian is an age (geology), age in the Early Triassic epoch (geology), epoch; in chronostratigraphy, it is a stage (stratigraphy), stage in the Lower Triassic series (stratigraphy), series. It spans the time between annum, Ma and Ma (million years ago). The Olenekian is sometimes divided into the Smithian and the Spathian subages or substages. The Olenekian follows the Induan and is followed by the Anisian (Middle Triassic). The Olenekian saw the deposition of a large part of the Buntsandstein in Europe. The Olenekian is roughly coeval with the regional Yongningzhenian Stage used in China. Stratigraphic definitions The Olenekian Stage was introduced into scientific literature by Russian stratigraphers in 1956. The stage is named after Olenëk in Siberia. Before the subdivision in Olenekian and Induan became established, both stages formed the Scythian Stage, which has since disappeared from the official timescale. The base of the Olenekian is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triassic
The Triassic ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is the first and shortest period of the Mesozoic Era and the seventh period of the Phanerozoic Eon. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary Rock
Sedimentary rocks are types of rock (geology), rock formed by the cementation (geology), cementation of sediments—i.e. particles made of minerals (geological detritus) or organic matter (biological detritus)—that have been accumulated or deposited at Earth's surface. Sedimentation is any process that causes these particles to settle in place. Geological detritus originates from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or Mass wasting, mass movement, which are called agents of denudation. Biological detritus is formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on the floor of water bodies (marine snow). Sedimentation may also occur when dissolved minerals precipitate from aqueous solution, water solution. The sedimentary rock cover of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karoo Basin
The Karoo Supergroup is the most widespread stratigraphic unit in Africa south of the Kalahari Desert. The supergroup consists of a sequence of units, mostly of nonmarine origin, deposited between the Late Carboniferous and Early Jurassic, a period of about 120 million years. In southern Africa, rocks of the Karoo Supergroup cover almost two thirds of the present land surface, making part of the 75% of sediments or sedimentary rocks covering the earth including all of Lesotho, almost the whole of Free State, and large parts of the Eastern Cape, Northern Cape, Mpumalanga and KwaZulu-Natal Provinces of South Africa. Karoo supergroup outcrops are also found in Namibia, Eswatini, Zambia, Zimbabwe and Malawi, as well as on other continents that were part of Gondwana. The basins in which it was deposited formed during the formation and breakup of Pangea.McCarthy, T., Rubridge, B. (2005). ''The Story of Earth and Life.'' pp. 161, 187–241. Struik Publishers, Cape Town The type area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drakensberg Group
The Drakensberg Group is a geological group named after the Drakensberg mountain range where in its uppermost sections the rocks are found. The Drakensberg Group lies over most of Lesotho and localities in the Eastern Cape, KwaZulu-Natal, and Free State (province), Free State provinces of South Africa. It forms part of the greater Karoo Igneous Province, which occurs over an extensive area of southern Africa. Background The Drakensberg Group was formed approximately 182 million years ago during the early Jurassic period. Rifting tectonics in response to the breakup of the supercontinent Gondwana are believed to have been the cause for the formation of the Drakensberg Group. Networks of hyperbyssal (shallow Intrusive rock, intrusives) Dike (geology), dikes and Sill (geology), sills represent the conduits through the Crust (geology), crust that brought basaltic and Andesite, andesitic lava to the surface, and caused the formation of the Extrusive rock, extrusive flood basalts o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beaufort Group
The Beaufort Group is the third of the main subdivisions of the Karoo Supergroup in South Africa. It is composed of a lower Adelaide Subgroup and an upper Tarkastad Subgroup. It follows conformably after the Ecca Group and unconformably underlies the Stormberg Group. Based on stratigraphic position, lithostratigraphic and biostratigraphic correlations, palynological analyses, and other means of geological dating, the Beaufort Group rocks are considered to range between Middle Permian ( Wordian) to Early Triassic (Anisian) in age. Background During the period when sedimentation of the Beaufort Group rocks took place, the Ecca sea had retreated to the northeastern Karoo Basin. All sediment deposition at this time took place in a terrestrial, although in a predominantly fluvial or alluvial environment that was seasonally arid. This environment covered a vast area and deposition was influenced by a retroarc foreland basin. This foreland system was caused by crustal uplif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clarens Formation
The Clarens Formation is a geological formation found in several localities in Lesotho and in the Free State, KwaZulu-Natal, and Eastern Cape provinces in South Africa. It is the uppermost of the three formations found in the Stormberg Group of the greater Karoo Supergroup rocks and represents the final phase of preserved sedimentation of the Karoo Basin. Geology The Clarens Formation is composed nearly entirely of fine to medium-grained, thickly-bedded sandstones that range from pale orange or pinkish to cream in color. It is characterized by its remarkable gross lithological uniformity and that its deposits mainly outcrop as high cliffs. These Clarens Formation cliffs frequently contain shallow caves and overhangs at the contact of the underlying Upper Elliot Formation (UEF) due to processes of erosion. This particular feature of the Clarens Formation lead to the initial naming of these rocks the “Cave Sandstone” in older literature. It is thought that the geographical ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elliot Formation
The Elliot Formation is a geological formation and forms part of the Stormberg Group, the uppermost geological group that comprises the greater Karoo Supergroup. Outcrops of the Elliot Formation have been found in the northern Eastern Cape, southern Free State, and in the eastern KwaZulu-Natal provinces of South Africa. Outcrops and exposures are also found in several localities in Lesotho such as Qacha's Neck, Hill Top, Quthing, and near the capital, Maseru. The Elliot Formation is further divided into the lower (LEF) and upper (UEF) Elliot formations to differentiate significant sedimentological differences between these layers. The LEF is dominantly Late Triassic (Norian-Hettangian) in age while the UEF is mainly Early Jurassic (Sinemurian- Pliensbachian) and is tentatively regarded to preserve a continental record of the Triassic-Jurassic boundary in southern Africa. This geological formation is named after the town of Elliot in the Eastern Cape, and its stratotype l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molteno Formation
The Molteno Formation is a geological formation found in several localities in Lesotho and South Africa. It lies mainly south of Maseru, near Burgersdorp, Aliwal North, Dordrecht, Molteno, and Elliot. It extends as far north as Matatiele in the Eastern Cape. The formation's localities lie along the Drakensberg Mountains in Kwazulu-Natal, and near Ladybrand in the Free State of South Africa. The Molteno Formation is the lowermost of the three formations in the Stormberg Group of the greater Karoo Supergroup. The Molteno Formation represents the initial phase of preserved sedimentation of the Stormberg Group. Geology The Molteno Formation is the lowermost geological formation of the Stormberg Group. It overlies the Burgersdorp Formation of the Beaufort Group, and underlies the lower Elliot Formation (LEF). Containing alternating finely-grained, medium-grained, and coarse-grained sandstones, the formation features greyish mudstone layers with the coarser sandstones exhibiting tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karoo Supergroup
The Karoo Supergroup is the most widespread stratigraphic unit in Africa south of the Kalahari Desert. The supergroup consists of a sequence of units, mostly of nonmarine origin, deposited between the Late Carboniferous and Early Jurassic, a period of about 120 million years. In southern Africa, rocks of the Karoo Supergroup cover almost two thirds of the present land surface, making part of the 75% of sediments or sedimentary rocks covering the earth including all of Lesotho, almost the whole of Free State, and large parts of the Eastern Cape, Northern Cape, Mpumalanga and KwaZulu-Natal Provinces of South Africa. Karoo supergroup outcrops are also found in Namibia, Eswatini, Zambia, Zimbabwe and Malawi, as well as on other continents that were part of Gondwana. The basins in which it was deposited formed during the formation and breakup of Pangea.McCarthy, T., Rubridge, B. (2005). ''The Story of Earth and Life.'' pp. 161, 187–241. Struik Publishers, Cape Town The type area o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
