|
North Atlantic Igneous Province
The North Atlantic Igneous Province (NAIP) is a large igneous province in the North Atlantic, centered on Iceland. In the Paleogene, the province formed the Thulean Plateau, a large basaltic lava plain, which extended over at least in area and in volume. The plateau was broken up during the opening of the North Atlantic Ocean leaving remnants preserved in north Ireland, west Scotland, the Faroe Islands, northwest Iceland, east Greenland, western Norway and many of the islands located in the north eastern portion of the North Atlantic Ocean. The igneous province is the origin of the Giant's Causeway and Fingal's Cave. The province is also known as Brito–Arctic province (also known as the North Atlantic Tertiary Volcanic Province) and the portion of the province in the British Isles is also called the British Tertiary Volcanic Province or British Tertiary Igneous Province. Formation Isotopic dating indicates the most active magmatic phase of the NAIP was between and c. 54.5 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Large Igneous Province
A large igneous province (LIP) is an extremely large accumulation of igneous rocks, including intrusive (sills, dikes) and extrusive (lava flows, tephra deposits), arising when magma travels through the crust towards the surface. The formation of LIPs is variously attributed to mantle plumes or to processes associated with divergent plate tectonics. The formation of some of the LIPs in the past 500 million years coincide in time with mass extinctions and rapid climatic changes, which has led to numerous hypotheses about causal relationships. LIPs are fundamentally different from any other currently active volcanoes or volcanic systems. Definition In 1992 researchers first used the term ''large igneous province'' to describe very large accumulations—areas greater than 100,000 square kilometers (approximately the area of Iceland)—of mafic igneous rocks that were erupted or emplaced at depth within an extremely short geological time interval: a few million years or less. Maf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mya (unit)
Mya may refer to: Brands and product names * Mya (program), an intelligent personal assistant created by Motorola * Mya (TV channel), an Italian Television channel * Midwest Young Artists, a comprehensive youth music program Codes * Burmese language, ISO 639-3 code is * Moruya Airport's IATA code * The IOC, license plate, and UNDP country code for Myanmar ("MYA") People * Mya (given name) * Mya (singer) (Mya Marie Harrison, born 1979), an American R&B singer-songwriter and actress * Bo Mya (1927–2006), nom de guerre of a Myanmar rebel leader, chief rapist of the Karen National Union Other uses * ''Mýa'' (album), a 1998 album by Mýa * ''Mya'' (bivalve), a genus of soft-shell clams * MYA (unit) for "million years ago", a science-related unit of time used in astronomy, geology and biology See also * A (motor yacht) (M/Y A), a superyacht * Maia (other) * Maya (other) Maya may refer to: Civilizations * Maya peoples, of southern Mexico and norther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ellesmere Island
Ellesmere Island ( iu, script=Latn, Umingmak Nuna, lit=land of muskoxen; french: île d'Ellesmere) is Canada's northernmost and List of Canadian islands by area, third largest island, and the List of islands by area, tenth largest in the world. It comprises an area of , slightly smaller than Great Britain, and the total length of the island is . Lying within the Arctic Archipelago, Ellesmere Island is considered part of the Queen Elizabeth Islands. Cape Columbia at 83°06′ is the northernmost point of land in Canada and one of the northernmost points of land on the planet (the northernmost point of land on Earth is the nearby Kaffeklubben Island of Greenland). The Arctic Cordillera mountain system covers much of Ellesmere Island, making it the most mountainous in the Arctic Archipelago. More than one-fifth of the island is protected as Quttinirpaaq National Park. In 2021, the population of Ellesmere Island was recorded at 144. There are three settlements: Alert, Nunavut, Aler ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Ocean
The Arctic Ocean is the smallest and shallowest of the world's five major oceans. It spans an area of approximately and is known as the coldest of all the oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, although some oceanographers call it the Arctic Mediterranean Sea. It has been described approximately as an estuary of the Atlantic Ocean. It is also seen as the northernmost part of the all-encompassing World Ocean. The Arctic Ocean includes the North Pole region in the middle of the Northern Hemisphere and extends south to about 60°N. The Arctic Ocean is surrounded by Eurasia and North America, and the borders follow topographic features: the Bering Strait on the Pacific side and the Greenland Scotland Ridge on the Atlantic side. It is mostly covered by sea ice throughout the year and almost completely in winter. The Arctic Ocean's surface temperature and salinity vary seasonally as the ice cover melts and freezes; its salinity is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Ridge
The Alpha Ridge is a major volcanic ridge under the Arctic Ocean between the Canada Basin (off Ellesmere Island) and the Lomonosov Ridge. It was active during the formation of the Amerasian Basin. It was discovered in 1963. The highest elevation is about 2,700 m over the ocean floor. It is 200 to 450 km wide. The Alpha Ridge, Lomonosov Ridge, and Nansen-Gakkel Ridge are the three major ranges that divide the Arctic Ocean floor, running generally parallel to each other. The 1983 Canadian Expedition to Study the Alpha Ridge (CESAR) seemed to establish that the Alpha Ridge is an extension of the continent from Ellesmere Island and hence there is a possibility that Canada may lay claim to the resource rights for the region, in particular for petroleum, according to the United Nations' Law of the Sea. There is no final conclusion to the issue so far, and part of the research planned for the European Drilling Research Icebreaker (''Aurora Borealis'') was drilling of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogeography
Palaeogeography (or paleogeography) is the study of historical geography, generally physical landscapes. Palaeogeography can also include the study of human or cultural environments. When the focus is specifically on landforms, the term paleogeomorphology is sometimes used instead. Paleomagnetism, paleobiogeography, and tectonic history are among its main tools. Palaeogeography yields information that is crucial to scientific understanding in a variety of contexts. For example, palaeogeographical analysis of sedimentary basins plays a key role in the field of petroleum geology, because ancient geomorphological environments of the Earth's surface are preserved in the stratigraphic record. Palaeogeographers also study the sedimentary environment associated with fossils for clues to the evolutionary development of extinct species. Palaeogeography is furthermore crucial to the understanding of palaeoclimatology, due to the impact of the positions of continents and oceans on infl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotope Geochemistry
Isotope geochemistry is an aspect of geology based upon the study of natural variations in the relative abundances of isotopes of various elements. Variations in isotopic abundance are measured by isotope ratio mass spectrometry, and can reveal information about the ages and origins of rock, air or water bodies, or processes of mixing between them. Stable isotope geochemistry is largely concerned with isotopic variations arising from mass-dependent isotope fractionation, whereas radiogenic isotope geochemistry is concerned with the products of natural radioactivity. Stable isotope geochemistry For most stable isotopes, the magnitude of fractionation from kinetic and equilibrium fractionation is very small; for this reason, enrichments are typically reported in "per mil" (‰, parts per thousand). These enrichments (δ) represent the ratio of heavy isotope to light isotope in the sample over the ratio of a standard. That is, :\delta \ce = \left( \frac -1 \right) \times 1000 â ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iceland Hotspot
The Iceland hotspot is a hotspot which is partly responsible for the high volcanic activity which has formed the Iceland Plateau and the island of Iceland. Iceland is one of the most active volcanic regions in the world, with eruptions occurring on average roughly every three years (in the 20th century there were 39 volcanic eruptions on and around Iceland). About a third of the basaltic lavas erupted in recorded history have been produced by Icelandic eruptions. Notable eruptions have included that of Eldgjá, a fissure of Katla, in 934 (the world's largest basaltic eruption ever witnessed), Laki in 1783 (the world's second largest), and several eruptions beneath ice caps, which have generated devastating glacial bursts, most recently in 2010 after the eruption of Eyjafjallajökull. Iceland's location astride the Mid-Atlantic Ridge, where the Eurasian and North American Plates are moving apart, is partly responsible for this intense volcanic activity, but an additional c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labrador
, nickname = "The Big Land" , etymology = , subdivision_type = Country , subdivision_name = Canada , subdivision_type1 = Province , subdivision_name1 = Newfoundland and Labrador , subdivision_type2 = , subdivision_name2 = , subdivision_type3 = , subdivision_name3 = , subdivision_type4 = , subdivision_name4 = , image_map = File:Labrador-Region.PNG , map_caption = Labrador (red) within Canada , pushpin_map = , pushpin_relief = , pushpin_map_caption = , coordinates = , coordinates_footnotes = , established_title = Founded , established_date = 1763 , area_footnotes = , area_total_km2 = ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seafloor Spreading
Seafloor spreading or Seafloor spread is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. History of study Earlier theories by Alfred Wegener and Alexander du Toit of continental drift postulated that continents in motion "plowed" through the fixed and immovable seafloor. The idea that the seafloor itself moves and also carries the continents with it as it spreads from a central rift axis was proposed by Harold Hammond Hess from Princeton University and Robert Dietz of the U.S. Naval Electronics Laboratory in San Diego in the 1960s. The phenomenon is known today as plate tectonics. In locations where two plates move apart, at mid-ocean ridges, new seafloor is continually formed during seafloor spreading. Significance Seafloor spreading helps explain continental drift in the theory of plate tectonics. When oceanic plates diverge, tensional stress causes fractures to occur in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rifting
In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben with normal faulting and rift-flank uplifts mainly on one side. Where rifts remain above sea level they form a rift valley, which may be filled by water forming a rift lake. The axis of the rift area may contain volcanic rocks, and active volcanism is a part of many, but not all, active rift systems. Major rifts occur along the central axis of most mid-ocean ridges, where new oceanic crust and lithosphere is created along a divergent boundary between two tectonic plates. ''Failed rifts'' are the result of continental rifting that failed to continue to the point of break-up. Typically the transition from rifting to spreading develops at a triple junction where three converging rifts meet over a hotspot. Two of these evolve to the poin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
