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Attborough Swallet
Attborough Swallet (also known as Red Quar Swallet) is a cave in Chewton Mendip in Somerset, England. It is unusual for a cave on the Mendip Hills in that it is formed from dolomite (rock), Dolomitic Conglomerate (geology), Conglomerate and Marl rather than ordinary limestone. The main part of the cave was first entered in 1992, although Red Quar Swallet had been dug in the 1930s and the entrance shaft is now a concrete pipe. It takes its name from the Attborough field in which the entrance is situated. Red Quar Swallet comes from the small scale quarrying of red Triassic conglomerate. The underground stream feeding water into the sump flows into Wigmore Swallet. See also * Caves of the Mendip Hills References {{Authority control Caves of the Mendip Hills ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chewton Mendip
Chewton Mendip is a village and civil parish in the Mendip district of Somerset, England. It is situated north of Wells, south of Bath and Bristol on the A39 very close to the A37. The village is in a valley on the Mendip Hills and is the source of the River Chew. The parish includes the hamlets of Bathway and Green Ore. History There were several lead mines and stone quarries in the parish. It is also the site of Attborough Swallet (also known as Red Quar Swallet), a cave which is unusual for a cave on the Mendip Hills in that it is not in limestone but instead in Dolomitic Conglomerate and Marl. The cave was first entered in 1992. There is a long barrow to the north of the village by . Excavation in 1946 revealed six Bronze Age barrows below the crest of the Mendips. The shape of some of the existing fields suggests they are of medieval origin. The parish was part of the hundred of Chewton. On 12 June 1643 the village was the site of a skirmish in the E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolomite (rock)
Dolomite (also known as dolomite rock, dolostone or dolomitic rock) is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite, CaMg(CO3)2. It occurs widely, often in association with limestone and evaporites, though it is less abundant than limestone and rare in Cenozoic rock beds (beds less than about 66 million years in age). The first geologist to distinguish dolomite rock from limestone was Belsazar Hacquet in 1778. Most dolomite was formed as a magnesium replacement of limestone or of lime mud before lithification. The geological process of conversion of calcite to dolomite is known as dolomitization and any intermediate product is known as dolomitic limestone. The "dolomite problem" refers to the vast worldwide depositions of dolomite in the past geologic record in contrast to the limited amounts of dolomite formed in modern times. Recent research has revealed sulfate-reducing bacteria living in anoxic conditions precipitate dolomite which ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conglomerate (geology)
Conglomerate () is a clastic sedimentary rock that is composed of a substantial fraction of rounded to subangular gravel-size clasts. A conglomerate typically contains a matrix of finer-grained sediments, such as sand, silt, or clay, which fills the interstices between the clasts. The clasts and matrix are typically cemented by calcium carbonate, iron oxide, silica, or hardened clay. Conglomerates form by the consolidation and lithification of gravel. They can be found in sedimentary rock sequences of all ages but probably make up less than 1 percent by weight of all sedimentary rocks. In terms of origin and depositional mechanisms, they are closely related to sandstones and exhibit many of the same types of sedimentary structures, e.g., tabular and trough cross-bedding and graded bedding.Boggs, S. (2006) ''Principles of Sedimentology and Stratigraphy.'', 2nd ed. Prentice Hall, New York. 662 pp. Friedman, G.M. (2003) ''Classification of sediments and sedimentary rocks.'' In G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marl
Marl is an earthy material rich in carbonate minerals, clays, and silt. When hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae. Marl makes up the lower part of the cliffs of Dover, and the Channel Tunnel follows these marl layers between France and the United Kingdom. Marl is also a common sediment in post-glacial lakes, such as the marl ponds of the northeastern United States. Marl has been used as a soil conditioner and neutralizing agent for acid soil and in the manufacture of cement. Description Marl or marlstone is a carbonate-rich mud or mudstone which contains variable amounts of clays and silt. The term was originally loosely applied to a variety of materials, most of which occur as loose, earthy deposits consisting chiefly of an intimate mixture of clay and calcium carbonate, formed under freshwater conditions. These typically contain 35–65% clay and 65–35% carbonate. The te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
