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Janet Vida Watson
Janet Vida Watson FRS FGS (1923–1985) was a British geologist. She was a professor of Geology at Imperial College, a rapporteur for the International Geological Correlation Program (IGCP) (1977–1982) and a vice president of the Royal Society (1983–1984). In 1982 she was elected president of the Geological Society of London, the first woman to occupy that position. She is well known for her contribution to the understanding of the Lewisian complex and as an author and co-author of several books including ''Beginning Geology'' and ''Introduction to Geology''. Personal life She was born 1 September 1923 in Hampstead, London. Her father; David M. S. Watson FRS was a vertebrate palaeontologist and a professor of zoology and comparative anatomy at the University of London. Her mother; Katharine M. Parker, did research in embryology prior to marriage. Janet Watson grew up alongside her sister, Katharine Mary in South Hampstead where she attended South Hampstead High ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hampstead
Hampstead () is an area in London, which lies northwest of Charing Cross, and extends from Watling Street, the A5 road (Roman Watling Street) to Hampstead Heath, a large, hilly expanse of parkland. The area forms the northwest part of the London Borough of Camden, a borough in Inner London which for the purposes of the London Plan is designated as part of Central London. Hampstead is known for its intellectual, liberal, artistic, musical, and literary associations. It has some of the most expensive housing in the London area. Hampstead has more millionaires within its boundaries than any other area of the United Kingdom.Wade, David"Whatever happened to Hampstead Man?" ''The Daily Telegraph'', 8 May 2004 (retrieved 3 March 2016). History Toponymy The name comes from the Old English, Anglo-Saxon words ''ham'' and ''stede'', which means, and is a cognate of, the Modern English "homestead". To 1900 Early records of Hampstead can be found in a grant by King Ethelred the Unread ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bournemouth
Bournemouth () is a coastal resort town in the Bournemouth, Christchurch and Poole council area of Dorset, England. At the 2011 census, the town had a population of 183,491, making it the largest town in Dorset. It is situated on the Southern England, English south coast, equidistant () from Dorchester, Dorset, Dorchester and Southampton. Bournemouth is part of the South East Dorset conurbation, which has a population of 465,000. Before it was founded in 1810 by Lewis Tregonwell, the area was a deserted heathland occasionally visited by fishermen and smugglers. Initially marketed as a health resort, the town received a boost when it appeared in Augustus Granville's 1841 book, ''The Spas of England''. Bournemouth's growth accelerated with the arrival of the railway, and it became a town in 1870. Part of the Historic counties of England, historic county of Hampshire, Bournemouth joined Dorset for administrative purposes following the Local Government Act 1972, reorganisation of l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleoproterozoic
The Paleoproterozoic Era (;, also spelled Palaeoproterozoic), spanning the time period from (2.5–1.6 Ga), is the first of the three sub-divisions (eras) of the Proterozoic Eon. The Paleoproterozoic is also the longest era of the Earth's geological history. It was during this era that the continents first stabilized. Paleontological evidence suggests that the Earth's rotational rate ~1.8 billion years ago equated to 20-hour days, implying a total of ~450 days per year. Atmosphere Before the enormous increase in atmospheric oxygen, almost all existing lifeforms were anaerobic organisms whose metabolism was based on a form of cellular respiration that did not require oxygen. Free oxygen in large amounts is toxic to most anaerobic organisms. Consequently, most died when the atmospheric free oxygen levels soared in an extinction event called the Great Oxidation Event, which brought atmospheric oxygen levels to up to 10% of their current level. The only creatures that survi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archean
The Archean Eon ( , also spelled Archaean or Archæan) is the second of four geologic eons of Earth's history, representing the time from . The Archean was preceded by the Hadean Eon and followed by the Proterozoic. The Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ... during the Archean was mostly a water world: there was continental crust, but much of it was under an ocean deeper than today's ocean. Except for some trace minerals, today's oldest continental crust dates back to the Archean. Much of the geological detail of the Archean has been destroyed by subsequent activity. The Earliest known life forms, earliest known life started in the Archean. Life was simple throughout the Archean, mostly represented by shallow-water microbial mats called stromatolites, and the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orogeny
Orogeny is a mountain building process. An orogeny is an event that takes place at a convergent plate margin when plate motion compresses the margin. An ''orogenic belt'' or ''orogen'' develops as the compressed plate crumples and is uplifted to form one or more mountain ranges. This involves a series of geological processes collectively called orogenesis. These include both structural deformation of existing continental crust and the creation of new continental crust through volcanism. Magma rising in the orogen carries less dense material upwards while leaving more dense material behind, resulting in compositional differentiation of Earth's lithosphere ( crust and uppermost mantle). A synorogenic process or event is one that occurs during an orogeny. The word "orogeny" () comes from Ancient Greek (, , + , , ). Although it was used before him, the term was employed by the American geologist G. K. Gilbert in 1890 to describe the process of mountain-building as distinguished f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Geology
Structural geology is the study of the three-dimensional distribution of rock units with respect to their deformational histories. The primary goal of structural geology is to use measurements of present-day rock geometries to uncover information about the history of deformation (strain) in the rocks, and ultimately, to understand the stress field that resulted in the observed strain and geometries. This understanding of the dynamics of the stress field can be linked to important events in the geologic past; a common goal is to understand the structural evolution of a particular area with respect to regionally widespread patterns of rock deformation (e.g., mountain building, rifting) due to plate tectonics. Use and importance The study of geologic structures has been of prime importance in economic geology, both petroleum geology and mining geology. Folded and faulted rock strata commonly form traps that accumulate and concentrate fluids such as petroleum and natural gas. Simil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphism
Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of chemically active fluids, but the rock remains mostly solid during the transformation. Metamorphism is distinct from weathering or diagenesis, which are changes that take place at or just beneath Earth's surface. Various forms of metamorphism exist, including regional, contact, hydrothermal, shock, and dynamic metamorphism. These differ in the characteristic temperatures, pressures, and rate at which they take place and in the extent to which reactive fluids are involved. Metamorphism occurring at increasing pressure and temperature conditions is known as ''prograde metamorphism'', while decreasing temperature and pressure characterize ''retrograde metamorphism''. Metamorphic petrology is the study of metamorphism. Metamorphic petrologists re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precambrian
The Precambrian (or Pre-Cambrian, sometimes abbreviated pꞒ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic Eon, which is named after Cambria, the Latinised name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time. The Precambrian is an informal unit of geologic time, subdivided into three eons ( Hadean, Archean, Proterozoic) of the geologic time scale. It spans from the formation of Earth about 4.6 billion years ago ( Ga) to the beginning of the Cambrian Period, about million years ago ( Ma), when hard-shelled creatures first appeared in abundance. Overview Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history, and what is known has largely been discovered from the 1960s onwards. The Precambrian fossil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sark
Sark (french: link=no, Sercq, ; Sercquiais: or ) is a part of the Channel Islands in the southwestern English Channel, off the coast of Normandy, France. It is a royal fief, which forms part of the Bailiwick of Guernsey, with its own set of laws based on Norman law and its own parliament. It has a population of about 500. Sark (including the nearby island of Brecqhou) has an area of . Little Sark is a peninsula joined by a natural but high and very narrow isthmus to the rest of Sark Island. Sark is one of the few remaining places in the world where cars are banned from roads and only tractors, bicycles and horse-drawn vehicles are allowed. In 2011, Sark was designated as a Dark Sky Community and the first Dark Sky Island in the world. Geography and geology Sark consists of two main parts, Greater Sark, located at about , and Little Sark to the south. They are connected by a narrow isthmus called La Coupée which is long and has a drop of on each side. Protective railin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Channel Islands
The Channel Islands ( nrf, Îles d'la Manche; french: îles Anglo-Normandes or ''îles de la Manche'') are an archipelago in the English Channel, off the French coast of Normandy. They include two Crown Dependencies: the Bailiwick of Jersey, which is the largest of the islands; and the Bailiwick of Guernsey, consisting of Guernsey, Alderney, Sark, Herm and some smaller islands. They are considered the remnants of the Duchy of Normandy and, although they are not part of the United Kingdom, the UK is responsible for the defence and international relations of the islands. The Crown dependencies are not members of the Commonwealth of Nations, nor have they ever been in the European Union. They have a total population of about , and the bailiwicks' capitals, Saint Helier and Saint Peter Port, have populations of 33,500 and 18,207, respectively. "Channel Islands" is a geographical term, not a political unit. The two bailiwicks have been administered separately since the late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sutherland
Sutherland ( gd, Cataibh) is a historic county, registration county and lieutenancy area in the Highlands of Scotland. Its county town is Dornoch. Sutherland borders Caithness and Moray Firth to the east, Ross-shire and Cromartyshire (later combined into Ross and Cromarty) to the south and the Atlantic to the north and west. Like its southern neighbour Ross-shire, Sutherland has some of the most dramatic scenery in Europe, especially on its western fringe where the mountains meet the sea. These include high sea cliffs, and very old mountains composed of Precambrian and Cambrian rocks. The name ''Sutherland'' dates from the era of Norwegian Viking rule and settlement over much of the Highlands and Islands, under the rule of the jarl of Orkney. Although it contains some of the northernmost land in the island of Great Britain, it was called ' ("southern land") from the standpoint of Orkney and Caithness. In Gaelic, the area is referred to according to its traditional areas: ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Migmatite
Migmatite is a composite rock found in medium and high-grade metamorphic environments, commonly within Precambrian cratonic blocks. It consists of two or more constituents often layered repetitively: one layer is an older metamorphic rock that was reconstituted subsequently by partial melting ("paleosome"), while the alternate layer has a pegmatitic, aplitic, granitic or generally plutonic appearance ("neosome"). Commonly, migmatites occur below deformed metamorphic rocks that represent the base of eroded mountain chains. Migmatites form under extreme temperature and pressure conditions during prograde metamorphism, when partial melting occurs in metamorphic paleosome. Components exsolved by partial melting are called neosome (meaning ‘new body’), which may or may not be heterogeneous at the microscopic to macroscopic scale. Migmatites often appear as tightly, incoherently folded veins ( ptygmatic folds).Recommendations by the IUGS Subcommission on the Systematics of M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
