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Amphibolite Point
Amphibolite Point () is a conspicuous, pyramidal point northwest of Saunders Point on the south coast of Coronation Island, in the South Orkney Islands. It was named by the Falkland Islands Dependencies Survey following their survey of 1948–49; there is a large amount of amphibolite on this point. Avalanche Corrie is an ice-filled cirque A (; from the Latin word ') is an amphitheatre-like valley formed by glacial erosion. Alternative names for this landform are corrie (from Scottish Gaelic , meaning a pot or cauldron) and (; ). A cirque may also be a similarly shaped landform ..., or corrie, close north of Amphibolite Point. It was so named by the Falkland Islands Dependencies Survey, because of the continuous avalanches from the hanging glaciers above the corrie. References Headlands of the South Orkney Islands {{SouthOrkneys-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Headland
A headland, also known as a head, is a coastal landform, a point of land usually high and often with a sheer drop, that extends into a body of water. It is a type of promontory. A headland of considerable size often is called a cape.Whittow, John (1984). ''Dictionary of Physical Geography''. London: Penguin, 1984, pp. 80, 246. . Headlands are characterised by high, breaking waves, rocky shores, intense erosion, and steep sea cliff. Headlands and bays are often found on the same coastline. A bay is flanked by land on three sides, whereas a headland is flanked by water on three sides. Headlands and bays form on discordant coastlines, where bands of rock of alternating resistance run perpendicular to the coast. Bays form when weak (less resistant) rocks (such as sands and clays) are eroded, leaving bands of stronger (more resistant) rocks (such as chalk, limestone, and granite) forming a headland, or peninsula. Through the deposition of sediment within the bay and the erosion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saunders Point
Saunders Point () is the southern extremity of the small island lying between Amphibolite Point and Tophet Bastion, off the south coast of Coronation Island in the South Orkney Islands. Charted by DI personnel from the ''Discovery II ''Discovery II'', built in 1971, is the second of three Discovery sternwheel riverboats operated by the Riverboat Discovery company. ''Discovery II'' is still in use as a tour vessel on the Chena and Tanana rivers near Fairbanks, Alaska. Hist ...'' in 1933. Named for A. Saunders who was aboard Discovery II and photographed the South Orkney Islands. Headlands of the South Orkney Islands {{SouthOrkneys-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coronation Island
Coronation Island is the largest of the South Orkney Islands, long and from wide. The island extends in a general east–west direction, is mainly ice-covered and comprises numerous bays, glaciers and peaks, the highest rising to . History The island was discovered in December 1821, in the course of the joint cruise by Captain Nathaniel Palmer, an American sealer, and Captain George Powell, a British sealer. Powell named the island in honour of the coronation of George IV, who had become king of the United Kingdom in 1820. Antarctic Specially Protected Area An area of some 92 km2 of north-central Coronation Island has been designated an Antarctic Specially Protected Area (ASPA 114), mainly for use as a relatively pristine reference site for use in comparative studies with more heavily impacted sites. It extends northwards from Brisbane Heights and Wave Peak in the central mountains to the coast between Conception Point in the west to Foul Point in the east. Most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Orkney Islands
The South Orkney Islands are a group of islands in the Southern Ocean, about north-east of the tip of the Antarctic Peninsula''Antarctica: Secrets of the Southern Continent'' p. 122 David McGonigal, 2009 and south-west of . They have a total area of about . The islands are claimed both by Britain (as part of the since 1962, previously as a [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falkland Islands Dependencies Survey
The British Antarctic Survey (BAS) is the United Kingdom's national polar research institute. It has a dual purpose, to conduct polar science, enabling better understanding of global issues, and to provide an active presence in the Antarctic on behalf of the UK. It is part of the Natural Environment Research Council (NERC). With over 400 staff, BAS takes an active role in Antarctic affairs, operating five research stations, one ship and five aircraft in both polar regions, as well as addressing key global and regional issues. This involves joint research projects with over 40 UK universities and more than 120 national and international collaborations. Having taken shape from activities during World War II, it was known as the Falkland Islands Dependencies Survey until 1962. History Operation Tabarin was a small British expedition in 1943 to establish permanently occupied bases in the Antarctic. It was a joint undertaking by the British Admiralty, Admiralty and the Secretary of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphibolite
Amphibolite () is a metamorphic rock that contains amphibole, especially hornblende and actinolite, as well as plagioclase feldspar, but with little or no quartz. It is typically dark-colored and dense, with a weakly foliated or schistose (flaky) structure. The small flakes of black and white in the rock often give it a salt-and-pepper appearance. Amphibolite frequently forms by metamorphism of mafic igneous rocks, such as basalt. However, because metamorphism creates minerals entirely based upon the chemistry of the protolith, certain 'dirty marls' and volcanic sediments may also metamorphose to an amphibolite assemblage. Deposits containing dolomite and siderite also readily yield amphibolite (tremolite-schist, grunerite-schist, and others) especially where there has been a certain amount of contact metamorphism by adjacent granitic masses. Metamorphosed basalt (metabasalt) creates ''ortho-amphibolite'' and other chemically appropriate lithologies create ''para-amphibolite' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cirque
A (; from the Latin word ') is an amphitheatre-like valley formed by glacial erosion. Alternative names for this landform are corrie (from Scottish Gaelic , meaning a pot or cauldron) and (; ). A cirque may also be a similarly shaped landform arising from fluvial erosion. The concave shape of a glacial cirque is open on the downhill side, while the cupped section is generally steep. Cliff-like slopes, down which ice and glaciated debris combine and converge, form the three or more higher sides. The floor of the cirque ends up bowl-shaped, as it is the complex convergence zone of combining ice flows from multiple directions and their accompanying rock burdens. Hence, it experiences somewhat greater erosion forces and is most often overdeepened below the level of the cirque's low-side outlet (stage) and its down-slope (backstage) valley. If the cirque is subject to seasonal melting, the floor of the cirque most often forms a tarn (small lake) behind a dam, which marks the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avalanche
An avalanche is a rapid flow of snow down a slope, such as a hill or mountain. Avalanches can be set off spontaneously, by such factors as increased precipitation or snowpack weakening, or by external means such as humans, animals, and earthquakes. Primarily composed of flowing snow and air, large avalanches have the capability to capture and move ice, rocks, and trees. Avalanches occur in two general forms, or combinations thereof: slab avalanches made of tightly packed snow, triggered by a collapse of an underlying weak snow layer, and loose snow avalanches made of looser snow. After being set off, avalanches usually accelerate rapidly and grow in mass and volume as they capture more snow. If an avalanche moves fast enough, some of the snow may mix with the air, forming a powder snow avalanche. Though they appear to share similarities, avalanches are distinct from slush flows, Mudflow, mudslides, Landslide#Debris landslide, rock slides, and serac collapses. They are also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hanging Glacier
A hanging glacier originates high on the wall of a glacial valley and descends only part of the way to the surface of the main glacier and abruptly stops, typically at a cliff. Avalanching and icefall An icefall is a portion of certain glaciers characterized by relatively rapid flow and chaotic crevassed surface, caused in part by gravity. The term ''icefall'' is formed by analogy with the word ''waterfall'', which is a similar phenomenon of t ...s are the mechanisms for ice and snow transfer to the valley floor below. Rock and icefall from a hanging glacier was responsible for triggering the Kolka-Karmadon rock ice slide in 2002, which killed 125 people. References Glaciology {{Glaciology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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