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Purbeck Limestone
Purbeck Marble is a fossiliferous limestone found in the Isle of Purbeck, a peninsula in south-east Dorset, England. It is a variety of Purbeck stone that has been quarried since at least Roman times as a decorative building stone. Geology Stratigraphically these limestone beds lie towards the top of the Durlston Formation of the Purbeck Group. They were deposited during the Berriasian age of the Early Cretaceous epoch. Purbeck Marble is not a metamorphic rock, like a true marble, but is so-called because it can take a fine polish. Its characteristic appearance comes from densely packed shells of the freshwater snail ''Viviparus''. Sussex Marble is similar in type. The 'marble' is properly classified as a biomicrudite, as it consists of large clasts (the snail shells) in a fine-grained limestone mud matrix. The individual marble beds (also known as 'seams'), lie between layers of softer marine clays and mudstone, laid down during repeated marine ingressions. Some of the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Folk Classification
The Folk classification, in geology, is a technical descriptive classification of sedimentary rocks devised by Robert L. Folk, an influential sedimentary petrologist and Professor Emeritus at the University of Texas. Folk's sandstone (clastic) classification Folk's philosophy is that the name of a rock must convey as much information as possible without being a complete description. For this, he proposed five important properties of sandstones to use as defining characteristics. These five properties are: grain size, chemically precipitated cements, textural maturity, miscellaneous transported constituents, and clan designation. Folk's fivefold name must be in the following format: :(Grain size): (chemically precipitated cements) (textural maturity) (miscellaneous transported constituents) (clan designation) However, Folk stated that cements and miscellaneous transported constituents are optional categories as they are not always observed. The other three properties should always ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Romano-British
The Romano-British culture arose in Britain under the Roman Empire following the Roman conquest in AD 43 and the creation of the province of Britannia. It arose as a fusion of the imported Roman culture with that of the indigenous Britons, a people of Celtic language and custom. Scholars such as Christopher Snyder believe that during the 5th and 6th centuries – approximately from 410 when the Roman legions withdrew, to 597 when St Augustine of Canterbury arrived – southern Britain preserved an active sub-Roman culture that survived the attacks from the Anglo-Saxons and even used a vernacular Latin when writing. Arrival of the Romans Roman troops, mainly from nearby provinces, invaded in AD 43, in what is now part of England, during the reign of Emperor Claudius. Over the next few years the province of Britannia was formed, eventually including the whole of what later became England and Wales and parts of Scotland.Kinder, H. & Hilgemann W. ''The Penguin Atlas of World ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Langton Matravers
Langton Matravers () is a village and civil parish on the Isle of Purbeck, in the county of Dorset in the south of England. It is situated about west of Swanage town centre and south-east of Corfe Castle. In the 2011 Census the civil parish had 381 households and a population of 853. History The name Langton stems from "long town", and is first attested in 1206, as ''Langeton''. Matravers stems from the name of John Mautravers who owned the land there in 1281, and ultimately originates from the French "mal traverse". The Old Malthouse was a preparatory school for boys and, more recently, girls which was founded in 1906, but closed in 2007. Two other preparatory schools Durnford School and Spyway used to be located in the village. Both Durnford and Spyway were closed earlier; Ian Fleming, author of the James Bond novels, was educated at Durnford. On 2 November 2022, the Ordnance Survey (OS) announced that the historic triple alignment of true, magnetic and grid north had made ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cist
A cist ( or ; also kist ; from grc-gre, κίστη, Middle Welsh ''Kist'' or Germanic ''Kiste'') is a small stone-built coffin-like box or ossuary used to hold the bodies of the dead. Examples can be found across Europe and in the Middle East. A cist may have been associated with other monuments, perhaps under a cairn or long barrow. Several cists are sometimes found close together within the same cairn or barrow. Often ornaments have been found within an excavated cist, indicating the wealth or prominence of the interred individual. This old word is preserved in the Nordic languages as "" in Swedish and "" in Danish and Norwegian, where it is the word for a funerary coffin. In English it is related to "cistern".''cistern'' Regional examples ;Sri Lanka * Bellanbedipalassa * Pothana * Ibbankatuwa Megalithic Stones * Udaranchamadama ;England * Bellever Forest, Dartmoor * Hepburn woods, Northumberland ;Estonia * Jõelähtme (Rebala) stone-cist graves, Harju County ;Gu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bronze Age
The Bronze Age is a historic period, lasting approximately from 3300 BC to 1200 BC, characterized by the use of bronze, the presence of writing in some areas, and other early features of urban civilization. The Bronze Age is the second principal period of the three-age system proposed in 1836 by Christian Jürgensen Thomsen for classifying and studying ancient societies and history. An ancient civilization is deemed to be part of the Bronze Age because it either produced bronze by smelting its own copper and alloying it with tin, arsenic, or other metals, or traded other items for bronze from production areas elsewhere. Bronze is harder and more durable than the other metals available at the time, allowing Bronze Age civilizations to gain a technological advantage. While terrestrial iron is naturally abundant, the higher temperature required for smelting, , in addition to the greater difficulty of working with the metal, placed it out of reach of common use until the end o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peveril Point
Peveril Point is a promontory on the east-facing coast of the Isle of Purbeck in Dorset, England, and is part of the town of Swanage. It forms the southern end of Swanage Bay. It is located at OS Grid Ref: SZ 041 787. The rocks that make up Peveril Point are shale and Portland and Purbeck limestone in a syncline structure. This has resisted erosion more than the adjacent clay of Swanage Bay; whilst the clay has eroded away over time, the limestone has remained as a promontory. On top of Peveril Point is a National Coastwatch Institution lookout. The point is also home to the Swanage lifeboat organisation. Ward, Lock and Company, ltd, & Hammond, R. J. W. (1974). ''Complete England''. London: Ward Lock, p. 94. Peveril Point contains tunnels connecting disused gun emplacements which defended the entrance to Southampton Water from the west of the Isle of Wight during World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Worbarrow Tout
Worbarrow Tout is a promontory at the eastern end of Worbarrow Bay on Isle of Purbeck in Dorset on the south coast of England, about south of Wareham and about west of Swanage. Immediately to its east is Pondfield Cove. Worbarrow Tout ("tout" means lookout) was originally part of Gad Cliff to its east, but sea erosion has virtually separated the two completely. Geology The Tout has a distinct pointed shape. It has steep angular layers of rock that visibly demonstrate the complex sedimentary folding that affected this area and that were caused by tectonic pressures as the African and European continents collided some 30 million years ago. The cliff sediments were then twisted horizontally and this is why the Chalks that are between 85 and 145 million years old are found at the rear of the bay. The sediments that face the sea at the front of the bay and form the peninsula Worbarrow Tout are the 150-million-year-old Portland limestones and 147-million-year-old Purbeck Beds. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Outcrop
An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth. Features Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial deposits are covered by soil and vegetation and cannot be seen or examined closely. However, in places where the overlying cover is removed through erosion or tectonic uplift, the rock may be exposed, or ''crop out''. Such exposure will happen most frequently in areas where erosion is rapid and exceeds the weathering rate such as on steep hillsides, mountain ridges and tops, river banks, and tectonically active areas. In Finland, glacial erosion during the last glacial maximum (ca. 11000 BC), followed by scouring by sea waves, followed by isostatic uplift has produced many smooth coastal and littoral outcrops. Bedrock and superficial deposits may also be exposed at the Earth's surface due to human excavations such as quarrying and build ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glauconite
Glauconite is an iron potassium phyllosilicate ( mica group) mineral of characteristic green color which is very friable and has very low weathering resistance. It crystallizes with a monoclinic geometry. Its name is derived from the Greek () meaning 'bluish green', referring to the common blue-green color of the mineral; its sheen ( mica glimmer) and blue-green color. Its color ranges from olive green, black green to bluish green, and yellowish on exposed surfaces due to oxidation. In the Mohs scale it has hardness of 2. The relative specific gravity range is 2.4 - 2.95. It is normally found in dark green rounded brittle pellets, and with the dimension of a sand grain size. It can be confused with chlorite (also of green color) or with a clay mineral. Glauconite has the chemical formula . Glauconite particles are one of the main components of greensand, glauconitic siltstone and glauconitic sandstone. Glauconite has been called a marl in an old and broad sense of that word. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limonite
Limonite () is an iron ore consisting of a mixture of hydrated iron(III) oxide-hydroxides in varying composition. The generic formula is frequently written as FeO(OH)·H2O, although this is not entirely accurate as the ratio of oxide to hydroxide can vary quite widely. Limonite is one of the three principal iron ores, the others being hematite and magnetite, and has been mined for the production of iron since at least 2500 BP. Names Limonite is named for the Greek word λειμών (/leː.mɔ̌ːn/), meaning "wet meadow", or λίμνη (/lím.nɛː/), meaning “marshy lake” as an allusion to its occurrence as '' bog iron ore'' in meadows and marshes. In its brown form it is sometimes called brown hematite or brown iron ore. Characteristics Limonite is relatively dense with a specific gravity varying from 2.7 to 4.3.Northrop, Stuart A. (1959) "Limonite" ''Minerals of New Mexico'' (revised edition) University of New Mexico Press, Albuquerque, New Mexico, pp. 329–333, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
