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Amundsen Basin
The Amundsen Basin, with depths up to , is the deepest abyssal plain in the Arctic Ocean, and contains the geographic North Pole. The Amundsen Basin is embraced by the Lomonosov Ridge (from to ) and the Gakkel Ridge (from to ). It is named after the polar researcher Roald Amundsen. Together with the Nansen Basin, the Amundsen Basin is often summarized as Eurasian Basin. The Russian-American cooperation Nansen and Amundsen Basin Observational SystemNABOS aims "to provide a quantitative observationally based assessment of circulation, water mass transformations, and transformation mechanisms in the Eurasian and Canadian Basins of the Arctic Ocean". Formation The Amundsen Basin formed during the Cenozoic Era from 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 Wegene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lomonosov Ridge
The Lomonosov Ridge (, ) is an unusual underwater ridge of continental crust in the Arctic Ocean. It spans between the New Siberian Islands over the central part of the ocean to Ellesmere Island of the Canadian Arctic Archipelago.CBC NewsBroken ship halts Russian expedition to claim Arctic seabed 25 July 2007. Retrieved 25 July 2007. The ridge divides the Arctic Basin into the Eurasian Basin and the Amerasian Basin. The width of the Lomonosov Ridge varies from . It rises above the deep seabed. The minimum depth of the ocean above the ridge is less than .GEUS 2014, page 12 Slopes of the ridge are relatively steep, broken up by canyons, and covered with layers of silt. It is an aseismic ridge. The Lomonosov Ridge was first discovered by the Soviet high-latitude expeditions in 1948 and is named after Mikhail Lomonosov. The name was approved by the GEBCO Sub-Committee on Undersea Feature Names ( SCUFN). 1979 LOREX expedition A Canadian scientific expedition, based out of Al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Profile Hg
The Arctic (; . ) is the polar region of Earth that surrounds the North Pole, lying within the Arctic Circle. The Arctic region, from the IERS Reference Meridian travelling east, consists of parts of northern Norway ( Nordland, Troms, Finnmark, Svalbard and Jan Mayen), northernmost Sweden ( Västerbotten, Norrbotten and Lappland), northern Finland ( North Ostrobothnia, Kainuu and Lappi), Russia ( Murmansk, Siberia, Nenets Okrug, Novaya Zemlya), the United States (Alaska), Canada ( Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), and northern Iceland ( Grímsey and Kolbeinsey), along with the Arctic Ocean and adjacent seas. Land within the Arctic region has seasonally varying snow and ice cover, with predominantly treeless permafrost under the tundra. Arctic seas contain seasonal sea ice in many places. The Arctic region is a unique area among Earth's ecosystems. The cultures in the region and the Arctic indigenous peoples have adapted t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abyssal Plain
An abyssal plain is an underwater plain on the deep ocean floor, usually found at depths between . Lying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth's surface. They are among the flattest, smoothest, and least explored regions on Earth. Abyssal plains are key geologic elements of oceanic basins, the other elements being an elevated mid-ocean ridge and flanking abyssal hills. The creation of the abyssal plain is the result of the spreading of the seafloor (plate tectonics) and the melting of the lower oceanic crust. Magma rises from above the asthenosphere (a layer of the upper mantle), and as this basaltic material reaches the surface at mid-ocean ridges, it forms new oceanic crust, which is constantly pulled sideways by spreading of the seafloor. Abyssal plains result from the blanketing of an originally uneven surface of oceanic crust by fine-grained sediments, mainly clay and silt. Much of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Ocean
The Arctic Ocean is the smallest and shallowest of the world's five oceanic divisions. It spans an area of approximately and is the coldest of the world's oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, although some oceanographers call it the Arctic Mediterranean Sea. It has also been described 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 the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographic North Pole
The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is the point in the Northern Hemisphere where the Earth's axis of rotation meets its surface. It is called the True North Pole to distinguish from the Magnetic North Pole. The North Pole is by definition the northernmost point on the Earth, lying antipodally to the South Pole. It defines geodetic latitude 90° North, as well as the direction of true north. At the North Pole all directions point south; all lines of longitude converge there, so its longitude can be defined as any degree value. No time zone has been assigned to the North Pole, so any time can be used as the local time. Along tight latitude circles, counterclockwise is east and clockwise is west. The North Pole is at the center of the Northern Hemisphere. The nearest land is usually said to be Kaffeklubben Island, off the northern coast of Greenland about away, though some perhaps semi-permanent gravel banks lie slightly clo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gakkel Ridge
The Gakkel Ridge (formerly known as the Nansen Cordillera and Arctic Mid-Ocean Ridge) is a mid-oceanic ridge, a divergent tectonic plate boundary between the North American Plate and the Eurasian Plate. It is located in the Eurasian Basin of the Arctic Ocean, between Greenland and Siberia. Geologically, it connects the northern end of the Mid-Atlantic Ridge with the Laptev Sea Rift. History The existence and approximate location of the Gakkel Ridge were predicted by Soviet polar explorer Yakov Yakovlevich Gakkel and confirmed on Soviet expeditions in the Arctic around 1950. The Ridge is named after him, and the name was recognized in April 1987 by SCUFN (under that body's old name, the Sub-Committee on Geographical Names and Nomenclature of Ocean Bottom Features). Until 1999, it was believed to be non-volcanic; that year, scientists operating from a nuclear submarine discovered active volcanoes along it. The largest, the Gakkel Ridge Caldera, is a supervolcano that erupte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roald Amundsen
Roald Engelbregt Gravning Amundsen (, ; ; 16 July 1872 – ) was a Norwegians, Norwegian explorer of polar regions. He was a key figure of the period known as the Heroic Age of Antarctic Exploration. Born in Borge, Østfold, Norway, Amundsen began his career as a polar explorer as first mate on Adrien de Gerlache's Belgian Antarctic Expedition of 1897–1899. From 1903 to 1906, he led the first expedition to successfully traverse the Northwest Passage on the sloop ''Gjøa''. In 1909, Amundsen began planning for a Amundsen's South Pole expedition, South Pole expedition. He left Norway in June 1910 on the ship ''Fram (ship), Fram'' and reached Antarctica in January 1911. His party established a Framheim, camp at the Bay of Whales and a series of supply depots on the Barrier (now known as the Ross Ice Shelf) before setting out for the pole in October. The party of five, led by Amundsen, became the first to reach the South Pole on 14 December 1911. Following a failed attemp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nansen Basin
The Nansen Basin (also Central Basin, formerly Fram Basin) is an abyssal plain with water-depths of around 3 km in the Arctic Ocean and (together with the deeper Amundsen Basin) part of the Eurasian Basin. It is named after Fridtjof Nansen. The Nansen Basin is bounded by the Gakkel Ridge on the one side and by the Barents Sea continental shelf on the other. The lowest point of the Arctic Ocean lies within the Nansen Basin and has a depth of 4,665 m. The Barents Abyssal Plain is located at the center of the Fram Basin. Oceanographic situation The Russian-American cooperation Nansen and Amundsen Basin Observational SystemNABOS aims "to provide a quantitative observationally based assessment of circulation, water mass transformations, and transformation mechanisms in the Eurasian and Canadian Basins of the Arctic Ocean". See also * Fram Strait The Fram Strait is the passage between Greenland and Svalbard, located roughly between 77th parallel north, 77°N and 81st paral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurasian Basin
The Eurasian Basin, or Eurasia Basin, is one of the two major basins into which the Arctic Basin of the Arctic Ocean is split by the Lomonosov Ridge (other being the Amerasia Basin). The Eurasia Basin may be seen as an extension of the North Atlantic Basin through Fram Strait. It is further split by the mid-ocean Gakkel Ridge into the Nansen Basin and the Amundsen Basin. The latter basin is the deepest one of the Arctic Ocean and the geographic North Pole is located there. The Eurasian Basin is bounded by Greenland, the Lomonosov Ridge, and the shelves of the Laptev Sea, Kara Sea and Barents Sea. The maximum depth within the Eurasian Basin is reached at the Litke Deep with 5449 m depth. Today, the Gakkel Ridge is the site of some of the slowest seafloor spreading on the Earth, with 10 mm/yr near the Fram Strait and 6 mm/yr near the Laptev Sea. Initial opening of the Eurasian Basin is constrained by magnetic anomaly and geologic information to the Cenozoic The Cenozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenozoic
The Cenozoic Era ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterized by the dominance of mammals, insects, birds and angiosperms (flowering plants). It is the latest of three geological eras of the Phanerozoic Eon, preceded by the Mesozoic and Paleozoic. The Cenozoic started with the Cretaceous–Paleogene extinction event, when many species, including the non-avian dinosaurs, became extinct in an event attributed by most experts to the impact of a large asteroid or other celestial body, the Chicxulub impactor. The Cenozoic is also known as the Age of Mammals because the terrestrial animals that dominated both hemispheres were mammalsthe eutherians ( placentals) in the Northern Hemisphere and the metatherians (marsupials, now mainly restricted to Australia and to some extent South America) in the Southern Hemisphere. The extinction of many groups allowed mammals and birds to greatly diversify so that large m ... [...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 i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilkes Basin
The Wilkes Basin is a large subglacial basin situated generally southward of George V Coast and westward of Prince Albert Mountains in East Antarctica. The feature is approximately 1400 km long and 400 km wide. The Wilkes Basin is considered to be the largest marine-based drainage basin in East Antarctica, and may be in a state of marine ice sheet instability, caused by warm water intrusion into the shelf cavities. History It was discovered by the United States Victoria Land Traverse of 1959–1960. It was named by the Advisory Committee on Antarctic Names (US-ACAN) (1961) for the proximity of the western portion of this feature to Wilkes Land, and for the explorations along George V Coast by the United States Exploring Expedition (1838–42) under Lieutenant Charles Wilkes, USN. Deglaciation A study reported in ''Nature Climate Change'' on May 5, 2014 says the marine ice trapped in the basin is at risk of melting over the next 200 years. If unstopped, the East Antar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
