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Crag And Tail
A crag (sometimes spelled cragg, or in Scotland craig) is a rocky hill or mountain, generally isolated from other high ground. Origin Crags are formed when a glacier or ice sheet passes over an area that contains a particularly resistant rock formation (often granite, a volcanic plug or some other volcanic structure). The force of the glacier erodes the surrounding softer material, leaving the rocky block protruding from the surrounding terrain. Frequently the crag serves as a partial shelter to softer material in the wake of the glacier, which remains as a gradual fan or ridge forming a tapered ramp (called the tail) up the leeward side of the crag. In older examples, or those latterly surrounded by the sea, the tail is often missing, having been removed by post-glacial erosion. Examples Examples of crag and tail formations include: * Castle Rock (the crag, site of Edinburgh Castle) and the Royal Mile (the tail), in Edinburgh, Scotland * Salisbury Crags and Arthur's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stirling
Stirling (; ; ) is a City status in the United Kingdom, city in Central Belt, central Scotland, northeast of Glasgow and north-west of Edinburgh. The market town#Scotland, market town, surrounded by rich farmland, grew up connecting the royal Stirling Castle, citadel, the medieval old town with its merchants and tradesmen, the Stirling Old Bridge, Old Bridge and the port. Located on the River Forth, Stirling is the administrative centre for the Stirling (council area), Stirling council area, and is traditionally the county town and historic county of Stirlingshire. Stirling's key position as the lowest bridging point of the River Forth before it broadens towards the Firth of Forth made it a focal point for travel north or south. It has been said that "Stirling, like a huge brooch clasps Scottish Highlands, Highlands and Scottish Lowlands, Lowlands together". The city's status as "Gateway to the Highlands" also historically lent it great strategic importance—the credo "he who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion Landforms
Erosion is the action of surface processes (such as Surface runoff, water flow or wind) that removes soil, Rock (geology), rock, or dissolved material from one location on the Earth's crust#Crust, Earth's crust and then sediment transport, transports it to another location where it is deposit (geology), deposited. Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as ''physical'' or ''mechanical'' erosion; this contrasts with ''chemical'' erosion, where soil or rock material is removed from an area by Solvation, dissolution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres. Agents of erosion include rainfall; bedrock wear in rivers; coastal erosion by the sea and Wind wave, waves; glacier, glacial Plucking (glaciation), plucking, Abrasion (geology), abrasion, and scour; areal flooding; Aeolian processes, wind abrasion; groundwater processes; and Mass wastin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacial Landforms
Glacial landforms are landforms created by the action of glaciers. Most of today's glacial landforms were created by the movement of large ice sheets during the Quaternary glaciations. Some areas, like Fennoscandia and the southern Andes, have extensive occurrences of glacial landforms; other areas, such as the Sahara, display rare and very old fossil glacial landforms. Erosional landforms As the glaciers expand, due to their accumulating weight of snow and ice they crush, abrade, ''and'' scour surfaces such as rocks and bedrock. The resulting erosional landforms include striations, cirques, glacial horns, arêtes, trim lines, U-shaped valleys, roches moutonnées, overdeepenings and hanging valleys. * Striations: grooves and indentations in rock outcrops, formed by the scraping of small sediments on the bottom of a glacier across the Earth's surface. The direction of striations display the direction the glacier was moving. * Cirque: Starting location for mountain gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glaciology
Glaciology (; ) is the scientific study of glaciers, or, more generally, ice and natural phenomena that involve ice. Glaciology is an interdisciplinary Earth science that integrates geophysics, geology, physical geography, geomorphology, climatology, meteorology, hydrology, biology, and ecology. The impact of glaciers on people includes the fields of human geography and anthropology. The discoveries of water ice on the Moon, Mars, Europa (moon), Europa and Pluto add an extraterrestrial component to the field, which is referred to as "astroglaciology". Overview A glacier is a persistent body of dense ice, a form of rock) formed from snow falling and accumulating over a long period of time; glaciers move very slowly, either descending from high mountains, as in valley glaciers, or moving outward from centers of accumulation, as in continental glaciers. Areas of study within glaciology include glacial history and the reconstruction of past glaciation. A glaciologist is a person ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holmes, Arthur
Arthur Holmes (14 January 1890 – 20 September 1965) was an English geologist who made two major contributions to the understanding of geology. He pioneered the use of radiometric dating of minerals, and was the first earth scientist to grasp the mechanical and thermal implications of mantle convection, which led eventually to the acceptance of plate tectonics. Life He was born in Hebburn, County Durham, near Newcastle upon Tyne, the son of David Holmes, a cabinet-maker, and his wife, Emily Dickinson. As a child, he lived in Low Fell, Gateshead, and attended the Gateshead Higher Grade School (later Gateshead Grammar School). At 17, he enrolled to study physics at the Royal College of Science (now Imperial College London), but took a course in geology in his second year, which settled his future, against the advice of his tutors. After graduation, he took a job prospecting for minerals in Mozambique. After six months, with no discoveries, he became so ill with malaria that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roche Moutonnée
In glaciology, a roche moutonnée (or sheepback) is a rock formation created by the passing of a glacier. The passage of glacial ice over underlying bedrock often results in asymmetric erosional forms as a result of abrasion on the "stoss" (upstream) side of the rock, and plucking (i.e. pieces cracked off) on the "lee" (downstream) side. Some geologists limit the term to features on scales of a metre to several hundred metresDouglas Benn and David Evans, ''Glaciers & Glaciation,'' Arnold, London, 1st ed. 1998 and refer to larger features as crag and tail, though they are formed in essentially the same way. Etymology The 18th-century Alpine explorer Horace-Bénédict de Saussure coined the term ''roches moutonnées'' in 1786. He saw in these rocks a resemblance to the wigs that were fashionable amongst French gentry in his era and which were smoothed over with mutton fat (hence ''moutonnée'') so as to keep the hair in place. The French term is often incorrectly interpreted as " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drumlin
A drumlin, from the Irish word ("little ridge"), first recorded in 1833, in the classical sense is an elongated hill in the shape of an inverted spoon or half-buried egg formed by glacial ice acting on underlying unconsolidated till or ground moraine. Assemblages of drumlins are referred to as fields or swarms; they can create a landscape which is often described as having a 'basket of eggs topography'. Morphology Drumlins occur in various shapes and sizes, including symmetrical (about the long axis), spindle, parabolic forms, and transverse asymmetrical forms. Generally, they are elongated, oval-shaped hills, with a long axis parallel to the orientation of ice flow and with an up-ice (stoss) face that is generally steeper than the down-ice (lee) face. Drumlins are typically between long and between wide. Drumlins generally have a length to width ratio of between 1.7 and 4.1 and it has been suggested that this ratio can indicate the velocity of the glacier. That is, since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West Antarctica
West Antarctica, or Lesser Antarctica, one of the two major regions of Antarctica, is the part of that continent that lies within the Western Hemisphere, and includes the Antarctic Peninsula. It is separated from East Antarctica by the Transantarctic Mountains and is covered by the West Antarctic Ice Sheet. It lies between the Ross Sea (partly covered by the Ross Ice Shelf), and the Weddell Sea (largely covered by the Filchner-Ronne Ice Shelf). It may be considered a giant peninsula, stretching from the South Pole towards the tip of South America. West Antarctica is largely covered by the Antarctic ice sheet, but there have been signs that climate change is having some effect and that this ice sheet may have started to shrink slightly. Over the past 50 years, the west coast of the Antarctic Peninsula has been – and still is – one of the most rapidly warming parts of the planet, and the coasts of the Peninsula are the only parts of West Antarctica that become (in summer) i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amundsen Sea
The Amundsen Sea is an arm of the Southern Ocean off Marie Byrd Land in western Antarctica. It lies between Cape Flying Fish (the northwestern tip of Thurston Island) 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. The sea is mostly ice-covered, and the Thwaites Ice Tongue protrudes into it. The ice sheet which drains into the Amundsen Sea averages about in thickness; roughly the size of the state of Texas, this area is known as the Amundsen Sea Embayment (ASE); it forms one of the three major ice-drainage basins of the West Antarctic Ice Sheet. Embayment The ice sheet that drains in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ailsa Craig
Ailsa Craig (; ) is an island of in the outer Firth of Clyde, west of mainland Scotland, upon which microgranite has long been quarried to make curling stones. The now-uninhabited island comprises the remains of a magmatic pluton formed during the same period of igneous activity as magmatic rocks on the nearby Isle of Arran. The island, colloquially known as " Paddy's Milestone" because it is halfway between Belfast and Glasgow, was a haven for Catholics during the Scottish Reformation in the 16th century, but is today a bird sanctuary, providing a home for huge numbers of gannets and an increasing number of puffins. Etymology The name ''Ailsa'' comes from the Gaelic ''Allasa(n)'', earlier ''Aldasain'', which is of obscure origin. It has been suggested that it represents a contraction of ''allt Shasann'', meaning "cliff of the Saxons" (cf. ''airer Saxan'', "coastland of the Saxon", a name applied to southwestern Scotland in an early Gaelic text). The "Saxons" in questio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scrabo Tower
Scrabo Tower is a high 19th-century lookout tower or folly that stands on Scrabo Hill near Newtownards in County Down, Northern Ireland. It provides wide views and is a landmark that can be seen from afar. It was built as a memorial to Charles Vane, 3rd Marquess of Londonderry and was originally known as the Londonderry Monument. Its architectural style is Scottish baronial architecture#Scottish Baronial Revival, Scottish Baronial Revival. Name and location Nowadays, the tower on Scrabo Hill is usually just called Scrabo Tower and is visited for its views and surroundings. However, its original name was Londonderry Monument or Memorial. That name referred to the Marquess of Londonderry, Marquesses of Londonderry and only indirectly to the city or county of that name, which is away. The marquesses owned much ground around the hill. The hill and tower rise over the town of Newtownards, east of Belfast. As the tower dominates the town, it is often used as an emblem for Newtowna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
