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Geosyncline
A geosyncline (originally called a geosynclinal) is an obsolete geological concept to explain orogens, which was developed in the late 19th and early 20th centuries, before the theory of plate tectonics was envisaged. Şengör (1982), p. 11 A geosyncline was described as a giant downward fold in the Earth's crust, with associated upward folds called geanticlines (or geanticlinals), that preceded the climax phase of orogenic deformation. History The geosyncline concept was first conceived by the American geologists 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. 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of his time, disapproved the concept of geosyncline, and in 1909 he argued against its use due to its association with outdated theories. Şengör (1982), p. 43 This did not prevent further development of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophiolite
An ophiolite is a section of Earth's oceanic crust and the underlying upper mantle that has been uplifted and exposed above sea level and often emplaced onto continental crustal rocks. The Greek word ὄφις, ''ophis'' (''snake'') is found in the name of ophiolites, because of the superficial texture of some of them. Serpentinite especially evokes a snakeskin. The suffix ''lite'' from the Greek ''lithos'' means "stone". Some ophiolites have a green color. The origin of these rocks, present in many mountainous massifs, remained uncertain until the advent of plate tectonic theory. Their great significance relates to their occurrence within mountain belts such as the Alps and the Himalayas, where they document the existence of former ocean basins that have now been consumed by subduction. This insight was one of the founding pillars of plate tectonics, and ophiolites have always played a central role in plate tectonic theory and the interpretation of ancient mountain bel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gustav Steinmann
Johann Heinrich Conrad Gottfried Gustav Steinmann (9 April 1856 – 7 October 1929) was a German geologist and paleontologist. He performed various studies in the Ural Mountains, North America, South America, the Caucasus and the Alps. Steinmann had a large number of scientific publications. He made contributions to the Theory of Evolution and to the study of the structural geology and orogeny of the Andes. In the Alps and Apennines Steinmann defined what later became known as "Steinmann's Trinity," the occurrence of serpentine, pillow lava, and chert. The recognition of Steinmann's Trinity served years later to build up the theory around seafloor spreading and plate tectonics. Steinmann himself interpreted ophiolites (the Trinity) using the geosyncline concept. His studies of ophiolites in the Apennines paved the way for the discovery of allochthonous nappes in the Alps and Apennines. South America Steinmann redefined the Navidad Formation in 1895, then called Pis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hans Stille
Hans Wilhelm Stille (8 October 1876 – 26 December 1966) was an influential 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 theory to explain orogeny. 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. This competing view rejected Earth contraction and argued for continental drift. Şengör (1982), p. 24 As Stille opposed continental drift he came to be labelled a "fixist". 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 area showing that between the Bohemian and Rhine massifs Mesoz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continental Drift
Continental drift is the hypothesis that the Earth's continents have moved over geologic time relative to each other, thus appearing to have "drifted" across the ocean bed. The idea of continental drift has been subsumed into the science of plate tectonics, which studies the movement of the continents as they ride on plates of the Earth's lithosphere. The speculation that continents might have 'drifted' was first put forward by Abraham Ortelius in 1596. A pioneer of the modern view of mobilism was the Austrian geologist Otto Ampferer.Helmut W. Flügel: Die virtuelle Welt des Otto Ampferer und die Realität seiner Zeit'. In: Geo. Alp., Vol. 1, 2004. The concept was independently and more fully developed by Alfred Wegener in 1912, but the hypothesis was rejected by many for lack of any motive mechanism. The English geologist Arthur Holmes later proposed mantle convection for that mechanism. History Early history Abraham Ortelius , Theodor Christoph Lilienthal (1756), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Émile Haug
Gustave Émile Haug (19 June 1861 - 28 August 1927) was a French geologist and paleontologist known for his contribution to the geosyncline theory. Career Émile Haug was born on 19 June 1861. In 1884 he received his doctorate in natural sciences from the University of Strasbourg with a dissertation on the ammonite genus ''Harpoceras'', titled "''Beiträge zu einer monographie der Ammonitengattung Harpoceras''". In 1897 he became '' maître de conférences'' at the Sorbonne in Paris, where in 1904 he was named a full professor of geology.Haug, Gustave Émile Sociétés savantes de France In 1902 he was appointed president of the Société géologique de France, and from 1917 to 1927, was a member of the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press A university pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...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 distinguishe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plate Tectonics
Plate tectonics (from the la, label= Late Latin, tectonicus, from the grc, τεκτονικός, lit=pertaining to building) is the generally accepted scientific theory that considers the Earth's lithosphere to comprise a number of large tectonic plates which have been slowly moving since about 3.4 billion years ago. The model builds on the concept of '' continental drift'', an idea developed during the first decades of the 20th century. Plate tectonics came to be generally accepted by geoscientists after seafloor spreading was validated in the mid to late 1960s. Earth's lithosphere, which is the rigid outermost shell of the planet (the crust and upper mantle), is broken 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: '' convergent'', '' divergent'', or '' transform''. Earthquakes, volcanic activity, mountain-building, and ocea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epeirogenic Movement
In geology, epeirogenic movement (from Greek ''epeiros'', land, and ''genesis'', birth) is upheavals or depressions of land exhibiting long wavelengths and little folding apart from broad undulations. The broad central parts of continents are called cratons, and are subject to epeirogeny. The movement may be one of subsidence toward, or of uplift from, the centre of the Earth. The movement is caused by a set of forces acting along an Earth radius, such as those contributing to isostasy and faulting in the lithosphere. Epeirogenic movement can be permanent or transient. Transient uplift can occur over a thermal anomaly due to convecting anomalously hot mantle, and disappears when convection wanes. Permanent uplift can occur when igneous material is injected into the crust, and circular or elliptical structural uplift (that is, without folding) over a large radius (tens to thousands of km) is one characteristic of a mantle plume. In contrast to epeirogenic movemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
