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What is the meaning of Tectonic plate?

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Definition of tectonic plate

Definition of tectonic plate

1. Concept of plate tectonics

A tectonic plate or lithospheric plate is a fragment of lithosphere that moves as internal block rigid without occurring deformation on the asthenosphere (exterior or upper mantle) of the Earth. The word tectonics comes from ancient Greek τέκτων, τέκτωνος: nominative and genitive singular of Builder, Carpenter, and the suffix ικα: relative to.
Plate tectonics is a theory that explains the structure and dynamics of the Earth's surface. It establishes that the lithosphere (the upper portion cold and rigid land) is fragmented into a series of plates that move on the asthenosphere.[citation needed] This theory also describes the movement of the plates, their addresses, and interactions. The Earth lithosphere is divided in large plates and minor plate or microplate. Seismic, volcanic and tectonic activity is concentrated at the edges of the plates. This leads to the formation of large chains and basins.
The Earth is the only planet in the solar system with active tectonic plates, although there is evidence that in ancient times Mars, Venus, and one of the Galilean satellites, such as Europe, were tectonically active.
Although the theory of plate tectonics was formally established in the ' 1960's and in «1970», in reality is product of more than two centuries of geological and geophysical observations.» In the 19th century, it was observed that in the remote past of the Earth, there were numerous sedimentary basins with stratigraphic thickness of up to ten times those observed in the interior of the continents, and that - then - unknown processes distorted them originated mountain ranges: mountainous successions of enormous dimensions that may include parallel mountain ranges.
These basins are named geosinclinales, and the process of deformation, orogenesis. Another discovery of the 19th century was the documentation of a mountain range or dorsal chain in the middle of the Atlantic Ocean, that subsequent observations showed that you stretched forming a continuous network all the oceans.
Significant progress on the problem of the formation of the geosinclinales and their orogenias took place between 1908 and 1912, when Alfred Wegener hypothesized that the landmasses were moving and that had fragmented from a supercontinent called Pangea. Such movements would have deformed sediments accumulated on their edges geosinclinales and originated new mountain ranges.
Wegener believed continents is glided over the surface of the Earth's crust under the oceans as a block of wood on a table, and that this was due to the tidal forces produced by the drift of the poles. However, it is soon showed that these forces are of the order of a diezmillonesima to a hundredth of a millionth of the force of gravity, which made it impossible to bend and lift the masses of mountain ranges.
By the plate tectonics theory finally explained that all these phenomena (continental drift, formation of continental and submarine ridges) are manifestations of processes of liberation of heat from the interior of the Earth. There are four processes to the heat:
• 1) The most important thing is the disintegration of radioactive elements existing in the mantle, which mainly are: 40 K (potassium 40), 238U (uranium 238), (uranium 235) 235U and 232Th (thorium 232).
(• 2) Residues of the original heat that Earth has acquired during its genesis.
(3) Heat • because it rubs by gravity, which leads to the displacement of elements heavy towards the Center, and the light upwards. In doing so, the friction generates heat.
• 4) Cools, the nucleus increases its size. A similar phenomenon occurs for water cooling, that doing so gives off heat.

2. Definition of tectonic plate

Tectonic plates are those portions of lithosphere that are located below the surface or the crust of the planet. Of rigid material and are located on the asthenosphere, a portion of the mantle much deeper and more complex. Tectonic plates are mounted against each other, and although they are rigid, rather than by the union with each other, so their movement is permanent and very evident or clear in some regions of the planet are not sustained. In the majority of cases, movement or shifting of the tectonic plates is stepless and do not sit on the daily life of societies. When these movements are evident for the human being we should speak of phenomena such as earthquakes, tsunamis, earthquakes, etc. Many times their movement can also put into action to volcanoes.
There are two types of tectonic plates on our planet: the ocean and the mixed. While the first (which are the most extensive due to the large amount of water that exists on the surface of the Earth) are those that underlie the oceans, the mixed can combine on the surface both oceans as continental surface. The latter are the most numerous since we found many small rather, but in short extension the first occupy the greater part of the global territory.
For greater effectiveness in their study, specialists have given names different to each one of the plates approximately at the end of the 20th century. Thus, we can speak of the Antarctic plate (the largest of all and that which lies to the South of the planet), plate of the Pacific, the North American plate, the African plate, Australian plate, the South American plate, the Eurasian plate and other minors who join the largest among themselves.
The permanent movement and displacement of some of these plates can be seen in the relief of the Earth's crust. Thus, with mountain ranges or higher territories places are those who have suffered millions of years ago, shock or superposition of two plates which ended with the emergence of earthly elevations. This is why that regions such as the West coast of the American continent or the area of Southeast Asia often face numerous earthquakes, tsunamis and earthquakes caused by the permanent action of the plates that underlie its surface.

3 Meaning of tectonic plate

Originating in the French word plaque, a plate may be some sort of table or iron that develops specific functions that are used to display information. Tectonically, on the other hand, is an adjective that, in the field of geology, is used to qualify what is linked to the structure of the crust of the Earth.
The concept of plate tectonics makes reference to segments of the lithosphere that moves on the upper mantle of the planet. Noteworthy is that the lithosphere is the terrestrial surface layer whose most important feature is the rigidity.
The lithosphere, therefore, consists of several tectonic plates that move and interact. In the regions of collision of tectonic plates the volcanic, seismic, promoting the development of elevations, and telluric activity.
The theory related to the origin and characteristics of tectonic plates was consolidated from the Decade of 1960. Scientific evidence holds that our planet is currently the only one in the Solar system which has a tectonic plates in activity, but it is believed that in ancient times, Venus and Mars also had plates of this type.
The major tectonic plates of the Earth are the Eurasian plate, the North American plate, the South American plate, the African plate, the Pacific plate, indoaustralian plate and the Antarctic plate. There are also secondary plates, microplates and other kinds of plates.
The plates may qualify according to the type of crust that present. You can distinguish between the continental crust (which has a thick half of thirty-five kilometres) and the oceanic crust (the thickness does not exceed the ten kilometers).

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