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Contracting Earth
Before the concept of plate tectonics, global cooling was a geophysical theory by James Dwight Dana, also referred to as the contracting earth theory. It suggested that the Earth had been in a molten state, and features such as mountains formed as it cooled and shrank. As the interior of the Earth cooled and shrank, the rigid crust would have to shrink and crumple. The crumpling could produce features such as mountain ranges. Application The Earth was compared to a cooling ball of iron, or a steam boiler with shifting boiler plates. By the early 1900s, it was known that temperature increased with increasing depth. With the thickness of the crust, the "boiler plates", being estimated at ten to fifty miles, the downward pressure would be hundreds of thousands of pounds per square inch. Although groundwater was expected to turn to steam at a great depth, usually the downward pressure would contain any steam. Steam's effect upon molten rock was suspected of being a cause of vo ...
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Plate Tectonics
Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by Earth science, geoscientists after seafloor spreading was validated in the mid-to-late 1960s. The processes that result in plates and shape Earth's crust are called ''tectonics''. Tectonic plates also occur in other planets and moons. Earth's lithosphere, the rigid outer shell of the planet including the crust (geology), crust and upper mantle, is fractured into seven or eight major plates (depending on how they are defined) and many minor plates or "platelets". Where the plates meet, their relative motion determines the type of plate boundary (or fault (geology), fault): , , or . The relative movement of the plates typically ranges from zero to 10 cm annu ...
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Caribbean
The Caribbean ( , ; ; ; ) is a region in the middle of the Americas centered around the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean, mostly overlapping with the West Indies. Bordered by North America to the north, Central America to the west, and South America to the south, it comprises numerous List of Caribbean islands, islands, cays, islets, reefs, and banks. It includes the Lucayan Archipelago, Greater Antilles, and Lesser Antilles of the West Indies; the Quintana Roo Municipalities of Quintana Roo#Municipalities, islands and Districts of Belize#List, Belizean List of islands of Belize, islands of the Yucatán Peninsula; and the Bay Islands Department#Islands, Bay Islands, Miskito Cays, Archipelago of San Andrés, Providencia and Santa Catalina, Archipelago of San Andrés, Providencia, and Santa Catalina, Corn Islands, and San Blas Islands of Central America. It also includes the coastal areas on the Mainland, continental mainland of the Americas bordering the ...
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Timeline Of The Development Of Tectonophysics
The evolution of tectonophysics is closely linked to the history of the continental drift and plate tectonics hypotheses. The continental drift/ Airy-Heiskanen isostasy hypothesis had many flaws and scarce data. The fixist/ Pratt-Hayford isostasy, the contracting Earth and the expanding Earth concepts had many flaws as well. The idea of continents with a permanent location, the geosyncline theory, the Pratt-Hayford isostasy, the extrapolation of the age of the Earth by Lord Kelvin as a black body cooling down, the contracting Earth, the Earth as a solid and crystalline body, is one school of thought. A lithosphere creeping over the asthenosphere is a logical consequence of an Earth with internal heat by radioactivity decay, the Airy-Heiskanen isostasy, thrust faults and Niskanen's mantle viscosity determinations. Introduction Christian creationism (Martin Luther) was popular until the 19th century, and the age of the Earth was thought to have been created circa 4,000 BC. T ...
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Expanding Earth
The expanding Earth or growing Earth was a hypothesis attempting to explain the position and relative movement of continents by increase in the volume of Earth. With the recognition of plate tectonics in 20th century, the idea has been abandoned and considered a pseudoscience. Different forms of the hypothesis Expansion with constant mass In 1834, during the second voyage of HMS ''Beagle'', Charles Darwin investigated stepped plains featuring raised beaches in Patagonia which indicated to him that a huge area of South America had been "uplifted to its present height by a succession of elevations which acted over the whole of this space with nearly an equal force". While his mentor Charles Lyell had suggested forces acting near the crust on smaller areas, Darwin hypothesized that uplift at this continental scale required "the gradual expansion of some central mass" f the Earth"acting by intervals on the outer crust" with the "elevations being concentric with form of globe (or ...
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Mercury (planet)
Mercury is the first planet from the Sun. It is a rocky planet with a trace atmosphere. While it is the List of Solar System objects by size, smallest and least massive planet of the Solar System, its surface gravity is slightly higher than that of Mars. The surface of Mercury is similar to Earth's Moon, heavily Impact crater, cratered, with expansive rupes system, generated from thrust faults, and bright ray systems, formed by ejecta. Its largest crater, Caloris Planitia, has a diameter of , which is about one-third the diameter of the planet (). Being the most inferior planet, inferior orbiting planet it appears in Earth's sky, always close to the Sun, either as a "morning star" or an "evening star". It stays most of the time the closest to all other planets and is the planet with the highest delta-v needed to travel to from all other planets of the Solar System. Mercury's sidereal year (88.0 Earth days) and sidereal day (58.65 Earth days) are in a 3:2 ratio. This relation ...
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Radioactive Decay
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered ''radioactive''. Three of the most common types of decay are Alpha decay, alpha, Beta decay, beta, and Gamma ray, gamma decay. The weak force is the Fundamental interactions, mechanism that is responsible for beta decay, while the other two are governed by the electromagnetic force, electromagnetic and nuclear forces. Radioactive decay is a randomness, random process at the level of single atoms. According to quantum mechanics, quantum theory, it is impossible to predict when a particular atom will decay, regardless of how long the atom has existed. However, for a significant number of identical atoms, the overall decay rate can be expressed as a decay constant or as a half-life. The half-lives of radioactive atoms have a huge range: f ...
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Geosyncline
A geosyncline (originally called a geosynclinal) is an obsolete geology, geological concept to explain orogeny, orogens, which was developed in the late 19th and early 20th centuries, before the theory of plate tectonics was envisaged.#Sengor1982, Şengör (1982), p. 11 A geosyncline was described as a giant downward fold in the crust (geology), Earth's crust, with associated upward folds called geanticlines (or geanticlinals), that preceded the climax phase of orogeny, orogenic deformation. History The geosyncline concept was first conceived by the American geologists James Hall (paleontologist), James Hall and James Dwight Dana in the mid-19th century, during the classic studies of the Appalachian Mountains. Émile Haug further developed the geosyncline concept, and introduced it to Europe in 1900.#Sengor1982, Şengör (1982), p. 26 Eduard Suess, a leading geologist of his time, disapproved the concept of geosyncline, and in 1909 he argued against its use due to its association w ...
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Hans Stille
Hans Wilhelm Stille (8 October 1876 – 26 December 1966) was an influential Germany, German geologist working primarily on tectonics and the collation of tectonic events during the Phanerozoic. Stille adhered to the contracting Earth hypothesis and together with Leopold Kober he worked on the geosyncline, geosyncline theory to explain orogeny.#Sengor1982, Şengör (1982), p. 23 Stille's ideas emerged in the aftermath of Eduard Suess' book ''Das Antlitz der Erde'' (1883–1909). Stille's and Kober's school of thought was one of two that emerged in the post-Suess era (the other being headed by Alfred Wegener and Émile Argand.) Their competing view rejected Earth contraction and argued for continental drift.#Sengor1982, Şengör (1982), p. 24 As Stille opposed continental drift he came to be labelled a "fixist".#Sengor1982, Şengör (1982), p. 30 Part of Stille's work dealt with massifs and sedimentary basins in Central Europe; differing from Suess' interpretations for the same are ...
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Leopold Kober
Leopold Kober (21 September 1883 – 6 September 1970), an Austrian geologist, proposed a number of (subsequently largely discredited) theories of orogeny and coined the term '' kratogen'' to describe stable continental crust, which was later shortened to ''kraton'' by Hans Stille. Kober, developing geosyncline theory, posited that stable blocks known as forelands move toward each other forcing the sediments of the intervening geosynclinal region to move over the forelands and forming marginal mountain ranges known as ''Randketten'', while leaving an intervening median mass known as the ''Zwischengebirge''. Linton, D. L. & Mosely, F. (1970), 'The Geological Ages', in the ''Cambridge Ancient History'', vol. 1A., pp. 17–18. Cambridge: Cambridge University Press Cambridge University Press was the university press of the University of Cambridge. Granted a letters patent by King Henry VIII in 1534, it was the oldest university press in the world. Cambridge University Press me ...
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Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea in the south. The Japanese archipelago consists of four major islands—Hokkaido, Honshu, Shikoku, and Kyushu—and List of islands of Japan, thousands of smaller islands, covering . Japan has a population of over 123 million as of 2025, making it the List of countries and dependencies by population, eleventh-most populous country. The capital of Japan and List of cities in Japan, its largest city is Tokyo; the Greater Tokyo Area is the List of largest cities, largest metropolitan area in the world, with more than 37 million inhabitants as of 2024. Japan is divided into 47 Prefectures of Japan, administrative prefectures and List of regions of Japan, eight traditional regions. About three-quarters of Geography of Japan, the countr ...
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Himalayas
The Himalayas, or Himalaya ( ), is a mountain range in Asia, separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the Earth's highest peaks, including the highest, Mount Everest. More than list of highest mountains on Earth, 100 peaks exceeding elevations of above sea level lie in the Himalayas. The Himalayas abut on or cross territories of Himalayan states, six countries: Nepal, China, Pakistan, Bhutan, India and Afghanistan. The sovereignty of the range in the Kashmir region is disputed among India, Pakistan, and China. The Himalayan range is bordered on the northwest by the Karakoram and Hindu Kush ranges, on the north by the Tibetan Plateau, and on the south by the Indo-Gangetic Plain. Some of the world's major rivers, the Indus River, Indus, the Ganges river, Ganges, and the Yarlung Tsangpo River, Tsangpo–Brahmaputra River, Brahmaputra, rise in the vicinity of the Himalayas, and their combined drainage basin is home to some 6 ...
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