Prydz Bay | |
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Location of Prydz Bay in Antarctica | |
Location | Princess Elizabeth Land |
Coordinates | 69°0′S75°0′E / 69.000°S 75.000°E |
Prydz Bay is a deep embayment of Antarctica between the Lars Christensen Coast and Ingrid Christensen Coast. The Bay is at the downstream end of a giant glacial drainage system that originates in the East Antarctic interior. The Lambert Glacier flows from Lambert Graben into the Amery Ice Shelf on the south-west side of Prydz Bay. Other major glaciers drain into the southern end of the Amery Ice Shelf at 73° S where the marine part of the system starts at the modern grounding zone.
The Amery Ice Shelf extends about 550 km north of the Lambert Glacier grounding zone and occupies a valley between 80 and 200 km wide. [1] Depths to the bed beneath the Amery Ice Shelf are poorly known in detail but it is clearly over-deepened, reaching around -2500 m MSL close to the grounding zone. [2] The Amery Ice Shelf occupies a very large U-shaped valley with exposed nunataks along the flanks reaching 1500 m in elevation and total relief as high as 3000 m.
Seaward of the Amery Ice Shelf, Prydz Bay shows bathymetry typical of glaciated margins with deeper water near the coast with a broad topographic basin, the Amery Depression that is around -700 m MSL along the front of the Amery Ice Shelf. The Amery Depression shoals gently to outer shelf banks around 100–200 m deep. The shelf break is at around 400–500 m. The western side of Prydz Bay features a broad trough crossing from the inner shelf to the shelf edge, Prydz Channel. It is around 100 km wide and is 500 m deep at the shelf break. It is a typical example of a cross-shelf glacial trough that occupy 40.2% of the area of the Antarctic continental shelf [3] and that are formed by fast-flowing ice streams. [4]
During the late Neogene, the Lambert Glacier–Amery Ice Shelf drainage system flowed across Prydz Bay in an ice stream that reached the shelf edge and built a trough mouth fan on the upper continental slope. The fan consists mostly of debris flow deposits derived from the melting out of subglacial debris at the grounding line at the continental shelf edge. Ocean Drilling Program Site 1167 indicates that thick debris flow intervals are separated by thin mudstone horizons deposited when the ice had retreated from the shelf edge. The bulk of the trough mouth fan was deposited prior to ~780,000 years ago with as few as three debris flow intervals deposited since then. [5]
Portions of the bay were sighted in January and February 1931 by Norwegian whalers and the British Australian New Zealand Antarctic Research Expedition (BANZARE). It was explored in February 1935 by Norwegian whaler Captain Klarius Mikkelsen in the ship Thorshavn, and was mapped in considerable detail from aerial photographs taken by the Lars Christensen Expedition of 1936–37. Named for Olaf Prydz, general manager of the Hvalfangernes Assuranceforening in Sandefjord, Norway.
Australia's Davis Station, Russian Progress, Romanian Law-Racoviță-Negoiță, Chinese Zhongshan Stations, and Indian Bharati station are located on Prydz Bay at the Larsemann Hills Oasis.
The geography of Antarctica is dominated by its south polar location and, thus, by ice. The Antarctic continent, located in the Earth's southern hemisphere, is centered asymmetrically around the South Pole and largely south of the Antarctic Circle. It is washed by the Southern Ocean or, depending on definition, the southern Pacific, Atlantic, and Indian Oceans. It has an area of more than 14.2 million km2. Antarctica is the largest ice desert in the world.
The Ross Sea is a deep bay of the Southern Ocean in Antarctica, between Victoria Land and Marie Byrd Land and within the Ross Embayment, and is the southernmost sea on Earth. It derives its name from the British explorer James Clark Ross who visited this area in 1841. To the west of the sea lies Ross Island and Victoria Land, to the east Roosevelt Island and Edward VII Peninsula in Marie Byrd Land, while the southernmost part is covered by the Ross Ice Shelf, and is about 200 miles (320 km) from the South Pole. Its boundaries and area have been defined by the New Zealand National Institute of Water and Atmospheric Research as having an area of 637,000 square kilometres (246,000 sq mi).
The Ross Ice Shelf is the largest ice shelf of Antarctica. It is several hundred metres thick. The nearly vertical ice front to the open sea is more than 600 kilometres (370 mi) long, and between 15 and 50 metres high above the water surface. Ninety percent of the floating ice, however, is below the water surface.
The Amundsen Sea is an arm of the Southern Ocean off Marie Byrd Land in western Antarctica. It lies between Cape Flying Fish to the east and Cape Dart on Siple Island to the west. Cape Flying Fish marks the boundary between the Amundsen Sea and the Bellingshausen Sea. West of Cape Dart there is no named marginal sea of the Southern Ocean between the Amundsen and Ross Seas. The Norwegian expedition of 1928–1929 under Captain Nils Larsen named the body of water for the Norwegian polar explorer Roald Amundsen while exploring this area in February 1929.
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Denman Glacier is a glacier 11 to 16 km wide, descending north some 110 km (70 mi), which debouches into the Shackleton Ice Shelf east of David Island, Queen Mary Land. It was discovered in November 1912 by the Western Base party of the Australasian Antarctic Expedition under Sir Douglas Mawson. Mawson named the glacier for Lord Denman, Governor-General of Australia in 1911, a patron of the expedition.
Pine Island Glacier (PIG) is a large ice stream, and the fastest melting glacier in Antarctica, responsible for about 25% of Antarctica's ice loss. The glacier ice streams flow west-northwest along the south side of the Hudson Mountains into Pine Island Bay, Amundsen Sea, Antarctica. It was mapped by the United States Geological Survey (USGS) from surveys and United States Navy (USN) air photos, 1960–66, and named by the Advisory Committee on Antarctic Names (US-ACAN) in association with Pine Island Bay.
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This article incorporates public domain material from "Prydz Bay". Geographic Names Information System . United States Geological Survey.