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Noronha Hotspot
Noronha hotspot is a hypothesized hotspot in the Atlantic Ocean. It has been proposed as the candidate source for volcanism in the Fernando de Noronha archipelago of Brazil, as well as of other volcanoes also in Brazil and even the Bahamas and the Central Atlantic Magmatic Province. The presence of a mantle plume is controversial owing to equivocal seismic tomography images of the mantle and the inconsistent age progression in the volcanoes, especially the Brazilian ones. General The Noronha hotspot is also known as the Fernando hotspot. The hotspot is located over the South America Plate, which moves west-southwestward at a rate of , and is considered to be part of a West African superplume. Candidate volcanoes Fernando de Noronha The Noronha hotspot is considered to be currently located beneath the Fernando de Noronha islands, and age trends in the archipelago are consistent with a hotspot pattern. Such a hotspot would presently be centered beneath the eastern part o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hotspots
Hotspot, Hot Spot or Hot spot may refer to: Places * Hot Spot, Kentucky, a community in the United States Arts, entertainment, and media Fictional entities * Hot Spot (comics), a name for the DC Comics character Isaiah Crockett * Hot Spot (Transformers), any of several characters Films * ''Hot Spot'' (1941 film), later retitled ''I Wake Up Screaming'' * ''Hot Spot'' (1945 film), a Private Snafu film * ''The Hot Spot'', a 1990 neo-noir film Other uses in arts, entertainment, and media * ''Hot Spot'' (board game), a 1979 board game published by Metagaming Concepts * "Hot Spot" (''Burn Notice''), a television episode * ''Hot Spot'' (musical), 1963 * "Hot Spot" (song), by Foxy Brown * ''Hotspot'' (album), a 2020 album by Pet Shop Boys * ''The Hot Spot'' (Podcast), a GameSpot podcast Computing * Hot spot (computer programming), a compute-intensive region of a program * Hot spot, an area which is customizable by users in software frameworks * Hotspot (Wi-Fi), a wireless n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seamount
A seamount is a large geologic landform that rises from the ocean floor that does not reach to the water's surface (sea level), and thus is not an island, islet or cliff-rock. Seamounts are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to in height. They are defined by oceanographers as independent features that rise to at least above the seafloor, characteristically of conical form.IHO, 2008. Standardization of Undersea Feature Names: Guidelines Proposal form Terminology, 4th ed. International Hydrographic Organization and Intergovernmental Oceanographic Commission, Monaco. The peaks are often found hundreds to thousands of meters below the surface, and are therefore considered to be within the deep sea. During their evolution over geologic time, the largest seamounts may reach the sea surface where wave action erodes the summit to form a flat surface. After they have subsided and sunk below the sea surface such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louisiana
Louisiana , group=pronunciation (French: ''La Louisiane'') is a U.S. state, state in the Deep South and South Central United States, South Central regions of the United States. It is the List of U.S. states and territories by area, 20th-smallest by area and the List of U.S. states and territories by population, 25th most populous of the List of U.S. states, 50 U.S. states. Louisiana is bordered by the state of Texas to the west, Arkansas to the north, Mississippi to the east, and the Gulf of Mexico to the south. A large part of its eastern boundary is demarcated by the Mississippi River. Louisiana is the only U.S. state with political subdivisions termed List of parishes in Louisiana, parishes, which are equivalent to County (United States), counties, making it one of only two U.S. states not subdivided into counties (the other being Alaska and its List of boroughs and census areas in Alaska, boroughs). The state's capital is Baton Rouge, Louisiana, Baton Rouge, and its larges ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithospheric
A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the portion of the upper mantle that behaves elastically on time scales of up to thousands of years or more. The crust and upper mantle are distinguished on the basis of chemistry and mineralogy. Earth's lithosphere Earth's lithosphere, which constitutes the hard and rigid outer vertical layer of the Earth, includes the crust and the uppermost mantle. The lithosphere is underlain by the asthenosphere which is the weaker, hotter, and deeper part of the upper mantle. The lithosphere–asthenosphere boundary is defined by a difference in response to stress. The lithosphere remains rigid for very long periods of geologic time in which it deforms elastically and through brittle failure, while the asthenosphere deforms viscously and accommodates strain through plastic deformation. The thickness of the lithosphere is thus considered to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotope Ratio
The term stable isotope has a meaning similar to stable nuclide, but is preferably used when speaking of nuclides of a specific element. Hence, the plural form stable isotopes usually refers to isotopes of the same element. The relative abundance of such stable isotopes can be measured experimentally (isotope analysis), yielding an isotope ratio that can be used as a research tool. Theoretically, such stable isotopes could include the radiogenic daughter products of radioactive decay, used in radiometric dating. However, the expression stable-isotope ratio is preferably used to refer to isotopes whose relative abundances are affected by isotope fractionation in nature. This field is termed stable isotope geochemistry. Stable-isotope ratios Measurement of the ratios of naturally occurring stable isotopes (isotope analysis) plays an important role in isotope geochemistry, but stable isotopes (mostly hydrogen, carbon, nitrogen, oxygen and sulfur) are also finding uses in ecological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magma
Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma is found beneath the surface of the Earth, and evidence of magmatism has also been discovered on other terrestrial planets and some natural satellites. Besides molten rock, magma may also contain suspended crystals and gas bubbles. Magma is produced by melting of the mantle or the crust in various tectonic settings, which on Earth include subduction zones, continental rift zones, mid-ocean ridges and hotspots. Mantle and crustal melts migrate upwards through the crust where they are thought to be stored in magma chambers or trans-crustal crystal-rich mush zones. During magma's storage in the crust, its composition may be modified by fractional crystallization, contamination with crustal melts, magma mixing, and degassing. Following its ascent through the crust, magma may feed a volcano and be extruded as lava, or it may solidify underground to form an intrusion, su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope 13C in the atmosphere was exceptionally low in comparison with the more common isotope 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ... Epoch. The Oligocene is the third and final epoch of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geothermal Gradient
Geothermal gradient is the rate of temperature change with respect to increasing depth in Earth's interior. As a general rule, the crust temperature rises with depth due to the heat flow from the much hotter mantle; away from tectonic plate boundaries, temperature rises in about 25–30 °C/km (72–87 °F/mi) of depth near the surface in most of the world. However, in some cases the temperature may drop with increasing depth, especially near the surface, a phenomenon known as ''inverse'' or ''negative'' geothermal gradient. The effects of weather, sun, and season only reach a depth of approximately 10-20 metres. Strictly speaking, ''geo''-thermal necessarily refers to Earth but the concept may be applied to other planets. In SI units, the geothermal gradient is expressed as °C/km, K/km, or mK/m. These are all equivalent. Earth's internal heat comes from a combination of residual heat from planetary accretion, heat produced through radioactive decay, latent hea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northeastern Brazil
The Northeast Region of Brazil ( pt, Região Nordeste do Brasil; ) is one of the five official and political regions of the country according to the Brazilian Institute of Geography and Statistics. Of Brazil's twenty-six states, it comprises nine: Maranhão, Piauí, Ceará, Rio Grande do Norte, Paraíba, Pernambuco, Alagoas, Sergipe and Bahia, along with the Fernando de Noronha archipelago (formerly a separate territory, now part of Pernambuco). Chiefly known as ''Nordeste'' ("Northeast") in Brazil, this region was the first to be colonized by the Portuguese and other European peoples, playing a crucial role in the country's history. ''Nordestes dialects and rich culture, including its folklore, cuisines, music and literature, became the most easily distinguishable across the country. To this day, ''Nordeste'' is known for its history and culture, as well as for its natural environment and its hot weather. ''Nordeste'' stretches from the Atlantic seaboard in the northeast a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fortaleza
Fortaleza (, locally , Portuguese for ''Fortress'') is the state capital of Ceará, located in Northeastern Brazil. It belongs to the Metropolitan mesoregion of Fortaleza and microregion of Fortaleza. It is Brazil's 5th largest city and the twelfth richest city in the country in GDP. It also has the third richest metropolitan area in the North and Northeast regions. It is an important industrial and commercial center of Brazil, the nation's eighth largest municipality in purchasing power. According to the Ministry of Tourism, the city reached the mark of second most desired destination of Brazil and fourth among Brazilian cities in tourists received. The BR-116, the most important highway of the country, starts in Fortaleza. The municipality is part of the Common Market of Mercosur Cities, and also the Brazilian state capital which is closest to Europe, from Lisbon, Portugal. To the north of the city lies the Atlantic Ocean; to the south are the municipalities of Pacat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pico Do Cabugi
The Pico do Cabugi, also known as the Serra do Cabuji or Serrote da Itaretama, is the only extinct volcano in Brazil which preserves its original form. It is 590 meters high and is located in the Cabugi Ecological State Park in the municipality of Angicos in the state of Rio Grande do Norte. Composed mainly of basaltic alkaline intrusive rocks, this volcano was the result of a major geological upheaval in the tertiary era which were responsible for various volcanic cones in the rocky state of Rio Grande do Norte. They have been dated using radioactive isotopes as the most recent of Brazilian igneous rocks (± 19 million years). The presence of small xenoliths indicate that these rocks have originated at a great depth (about 60 km). The researcher Lenine Pinto argues that when Brazil was first discovered by Pedro Álvares Cabral, it was Pico do Cabugi that he first saw and not Monte Pascoal Monte Pascoal is a mountain to the south of the city of Porto Seguro, in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
