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Pridhamsleigh Cavern
Pridhamsleigh Cavern is a cave on the outskirts of Ashburton, Devon, England. It is approximately 1.1 kilometres in length with a total depth of just over 50 metres including Prid II. Pridhamsleigh is a good site for novice cavers, making it quite muddy throughout. It has a large variety of passages which lends itself to longer explorations. Due to the nature of the connecting and unconnecting overlapping phreatic passages in the cave, surveys (maps) of the cave are hard to interpret. The cave contains 'Bishops Chamber', a wide chamber close to the entrance from where most routes lead, and 'The Lake'. This elongated pool is over 100 feet deep. In the early 1970s divers with SCUBA gear discovered, at a depth of about 80 feet, a window into second partially air-filled chamber, with no passages leading off it. This chamber is the biggest in Devon and is named Gerry's Chamber after its discoverer, the late Gerry Pritchard. An accurate, hand-drawn, plan of the cave is held ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ashburton, Devon
Ashburton is a town on the south-southeastern edge of Dartmoor in Devon, England, adjacent to the A38. The town is 20 miles (32 km) northeast of Plymouth and 17 miles (27 km) southwest of Exeter. It was formerly important as a stannary town (a centre for the administration of tin-mining), and remains the largest town within the national park. Ashburton has five pubs within the centre of town and five restaurants/cafés. The town is also part of the electoral ward named ''Ashburton and Buckfastleigh'', the population of which at the 2011 census was 7,718. History The town's name derives from the Old English ''æsc-burna-tun'' meaning 'farm/settlement with a stream frequented by ash trees'. The name is recorded in the Domesday Book (1086) as ''Essebretone''. Ashburton was then the main town of the Parish of Ashburton, in Teignbridge Hundred. During the English Civil War, Ashburton was a temporary refuge for Royalist troops fleeing after their defeat by General Fairf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite, a closely related rock, which contains a high percentage of the mineral dolomite, . ''Magnesian limestone'' is an obsolete and poorly-defined term used variously for dolomite, for limes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cave
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea caves, rock shelters, and grottos, that extend a relatively short distance into the rock and they are called ''exogene'' caves. Caves which extend further underground than the opening is wide are called ''endogene'' caves. Speleology is the science of exploration and study of all aspects of caves and the cave environment. Visiting or exploring caves for recreation may be called ''caving'', ''potholing'', or ''spelunking''. Formation types The formation and development of caves is known as ''speleogenesis''; it can occur over the course of millions of years. Caves can range widely in size, and are formed by various geological processes. These may involve a combination of chemical processes, erosion by water, tectonic forces, microorgani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devon
Devon ( , historically known as Devonshire , ) is a ceremonial and non-metropolitan county in South West England. The most populous settlement in Devon is the city of Plymouth, followed by Devon's county town, the city of Exeter. Devon is a coastal county with cliffs and sandy beaches. Home to the largest open space in southern England, Dartmoor (), the county is predominately rural and has a relatively low population density for an English county. The county is bordered by Somerset to the north east, Dorset to the east, and Cornwall to the west. The county is split into the non-metropolitan districts of East Devon, Mid Devon, North Devon, South Hams, Teignbridge, Torridge, West Devon, Exeter, and the unitary authority areas of Plymouth, and Torbay. Combined as a ceremonial county, Devon's area is and its population is about 1.2 million. Devon derives its name from Dumnonia (the shift from ''m'' to ''v'' is a typical Celtic consonant shift). During the Briti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
England
England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe by the North Sea to the east and the English Channel to the south. The country covers five-eighths of the island of Great Britain, which lies in the North Atlantic, and includes over 100 smaller islands, such as the Isles of Scilly and the Isle of Wight. The area now called England was first inhabited by modern humans during the Upper Paleolithic period, but takes its name from the Angles, a Germanic tribe deriving its name from the Anglia peninsula, who settled during the 5th and 6th centuries. England became a unified state in the 10th century and has had a significant cultural and legal impact on the wider world since the Age of Discovery, which began during the 15th century. The English language, the Anglican Church, and Engli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phreatic
''Phreatic'' is a term used in hydrology to refer to aquifers, in speleology to refer to cave passages, and in volcanology to refer to a type of volcanic eruption. Hydrology The term phreatic (the word originates from the Greek , meaning "well" or "spring") is used in hydrology and the earth sciences to refer to matters relating to ground water (an aquifer) below the water table. The term 'phreatic surface' indicates the location where the pore water pressure is under atmospheric conditions (i.e. the pressure head is zero). This surface normally coincides with the water table. The slope of the phreatic surface is assumed to indicate the direction of ground water movement in an unconfined aquifer. The phreatic zone, below the phreatic surface where rock and soil is saturated with water, is the counterpart of the vadose zone, or unsaturated zone, above. Unconfined aquifers are also referred to as phreatic aquifers because their upper boundary is provided by the phreatic surface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niphargus
''Niphargus'' is by far the largest genus of its family, the Niphargidae, and the largest of all freshwater amphipod genera. Usually, these animals inhabit caves or groundwater. They occur in western Eurasia, in regions that were not covered by the Pleistocene ice sheets. They are found throughout most of Europe with the notable exception of the Nordics and they are also largely missing from Iberia. The genus extends into Asia as far as the Arabian Peninsula and Iran. In their main range – the central Mediterranean region through Central and Eastern Europe to the Ukraine – they are among the most significant organisms inhabiting the groundwater. In the Dinaric Alps alone there are at least 45 species. There are also six species in the British Isles (the northernmost ''Niphargus''): ''N. aquilex'', ''N. fontanus'', ''N. glenniei'' and ''N. kochianus'' of Great Britain, and ''N. irlandicus'' and ''N. wexfordensis'' of Ireland. Although the individual species often have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caves Of Devon
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea caves, rock shelters, and grottos, that extend a relatively short distance into the rock and they are called ''exogene'' caves. Caves which extend further underground than the opening is wide are called ''endogene'' caves. Speleology is the science of exploration and study of all aspects of caves and the cave environment. Visiting or exploring caves for recreation may be called ''caving'', ''potholing'', or ''spelunking''. Formation types The formation and development of caves is known as '' speleogenesis''; it can occur over the course of millions of years. Caves can range widely in size, and are formed by various geological processes. These may involve a combination of chemical processes, erosion by water, tectonic forces, microorgani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
