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Burma Plate
The Burma Plate is a minor tectonic plate or microplate located in Southeast Asia, sometimes considered a part of the larger Eurasian Plate. The Andaman Islands, Nicobar Islands, and northwestern Sumatra are located on the plate. This island arc separates the Andaman Sea from the main Indian Ocean to the west. To its east lies the Sunda Plate, from which it is separated along a transform boundary, running in a rough north-south line through the Andaman Sea. This boundary between the Burma and Sunda plates is a marginal seafloor spreading centre, which has led to the opening up of the Andaman Sea (from a southerly direction) by "pushing out" the Andaman-Nicobar-Sumatra island arc from mainland Asia, a process which began in earnest approximately 4 million years ago. To the west is the much larger India Plate, which is subducting beneath the western facet of the Burma Plate. This extensive subduction zone has formed the Sunda Trench. Tectonic history In models of the reconst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Tectonic Plates
This is a list of tectonic plates on Earth's surface. Tectonic plates are pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere. The plates are around thick and consist of two principal types of material: oceanic crust (also called '' sima'' from silicon and magnesium) and continental crust (''sial'' from silicon and aluminium). The composition of the two types of crust differs markedly, with mafic basaltic rocks dominating oceanic crust, while continental crust consists principally of lower-density felsic granitic rocks. Current plates Geologists generally agree that the following tectonic plates currently exist on Earth's surface with roughly definable boundaries. Tectonic plates are sometimes subdivided into three fairly arbitrary categories: ''major'' (or ''primary'') ''plates'', ''minor'' (or ''secondary'') ''plates'', and ''microplates'' (or ''tertiary plates''). Major plates These plates comprise the bulk of the continents an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indo-Australian Plate
The Indo-Australian Plate is a major tectonic plate that includes the continent of Australia and the surrounding ocean and extends northwest to include the Indian subcontinent and the adjacent waters. It was formed by the fusion of the Indian and the Australian Plates approximately 43 million years ago. The fusion happened when the mid-ocean ridge in the Indian Ocean, which separated the two plates, ceased spreading. Regions India, Australia, New Guinea, Tasmania, New Zealand, and New Caledonia are all fragments of the ancient supercontinent of Gondwana. As the ocean floor broke apart, these land masses fragmented from one another, and for a time these centers were thought to be dormant and fused into a single plate. However, research in the early 21st century indicates plate separation of the Indo-Australian Plate may have already occurred. Characteristics The eastern side of the plate is the convergent boundary with the Pacific plate. The Pacific plate sinks below the Au ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angle
In Euclidean geometry, an angle is the figure formed by two rays, called the '' sides'' of the angle, sharing a common endpoint, called the '' vertex'' of the angle. Angles formed by two rays lie in the plane that contains the rays. Angles are also formed by the intersection of two planes. These are called dihedral angles. Two intersecting curves may also define an angle, which is the angle of the rays lying tangent to the respective curves at their point of intersection. ''Angle'' is also used to designate the measure of an angle or of a rotation. This measure is the ratio of the length of a circular arc to its radius. In the case of a geometric angle, the arc is centered at the vertex and delimited by the sides. In the case of a rotation, the arc is centered at the center of the rotation and delimited by any other point and its image by the rotation. History and etymology The word ''angle'' comes from the Latin word ''angulus'', meaning "corner"; cognate words are the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergent Boundary
A convergent boundary (also known as a destructive boundary) is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a plane where many earthquakes occur, called the Wadati–Benioff zone. These collisions happen on scales of millions to tens of millions of years and can lead to volcanism, earthquakes, orogenesis, destruction of lithosphere, and deformation. Convergent boundaries occur between oceanic-oceanic lithosphere, oceanic-continental lithosphere, and continental-continental lithosphere. The geologic features related to convergent boundaries vary depending on crust types. Plate tectonics is driven by convection cells in the mantle. Convection cells are the result of heat generated by the radioactive decay of elements in the mantle escaping to the surface and the return of cool materials from the surface to the mantle. These convection cells bring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Counterclockwise
Two-dimensional rotation can occur in two possible directions. Clockwise motion (abbreviated CW) proceeds in the same direction as a clock's hands: from the top to the right, then down and then to the left, and back up to the top. The opposite sense of rotation or revolution is (in Commonwealth English) anticlockwise (ACW) or (in North American English) counterclockwise (CCW). Terminology Before clocks were commonplace, the terms " sunwise" and "deasil", "deiseil" and even "deocil" from the Scottish Gaelic language and from the same root as the Latin "dexter" ("right") were used for clockwise. "Widdershins" or "withershins" (from Middle Low German "weddersinnes", "opposite course") was used for counterclockwise. The terms clockwise and counterclockwise can only be applied to a rotational motion once a side of the rotational plane is specified, from which the rotation is observed. For example, the daily rotation of the Earth is clockwise when viewed from above the South ... [...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] |
Capricorn Plate
The Capricorn Plate is a proposed minor tectonic plate lying beneath the Indian Ocean basin in the southern and eastern hemispheres. The original theory of plate tectonics as accepted by the scientific community in the 1960s assumed fully rigid plates and relatively narrow, distinct plate boundaries. However, research in the late 20th and early 21st centuries suggests that certain plate junctions are diffuse across several dozen or even hundred kilometres. The Capricorn Plate is a relatively rigid piece of oceanic crust along the far western edge of the former Indo-Australian Plate. The Capricorn Plate was once joined with the Indian Plate and the Australian Plate to form the Indo-Australian Plate The Indo-Australian Plate is a major tectonic plate that includes the continent of Australia and the surrounding ocean and extends northwest to include the Indian subcontinent and the adjacent waters. It was formed by the fusion of the Indian an ..., but recent studies suggest that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Plate
The Australian Plate is a major tectonic plate in the eastern and, largely, southern hemispheres. Originally a part of the ancient continent of Gondwana, Australia remained connected to India and Antarctica until approximately when India broke away and began moving north. Australia and Antarctica began rifting and completely separated roughly . The Australian plate later fused with the adjacent Indian Plate beneath the Indian Ocean to form a single Indo-Australian Plate. However, recent studies suggest that the two plates have once again split apart and have been separate plates for at least 3 million years and likely longer. The Australian Plate includes the continent of Australia, including Tasmania, as well as portions of New Guinea, New Zealand and the Indian Ocean basin. Scope The continental crust of this plate covers the whole of Australia, the Gulf of Carpentaria, southern New Guinea, the Arafura Sea, the Coral Sea. The continental crust also includes northwester ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Himalaya
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 planet's highest peaks, including the very highest, Mount Everest. Over 100 peaks exceeding in elevation lie in the Himalayas. By contrast, the highest peak outside Asia (Aconcagua, in the Andes) is tall. The Himalayas abut or cross five countries: Bhutan, India, Nepal, China, and Pakistan. 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, the Ganges, and the Tsangpo– Brahmaputra, rise in the vicinity of the Himalayas, and their combined drainage basin is home to some 600 million people; 53 million people live in the Himalayas. The Himalayas hav ... [...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 distinguis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annum
A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the planet, four seasons are generally recognized: spring, summer, autumn and winter. In tropical and subtropical regions, several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual wet and dry seasons are recognized and tracked. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars. For the Gregorian calendar, the average length of the calendar year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Period
The geologic time scale, or geological time scale, (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (scientific branch of geology that aims to determine the age of rocks). It is used primarily by Earth scientists (including geologists, paleontologists, geophysicists, geochemists, and paleoclimatologists) to describe the timing and relationships of events in geologic history. The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies, paleomagnetic properties, and fossils. The definition of standardized international units of geologic time is the responsibility of the International Commission on Stratigraphy (ICS), a constituent body of the International Union of Geological Sciences (IUGS), whose primary objective is to precis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
