plate tectonics

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plate tectonics

n.
1. (used with a sing. verb) A theory that explains the global distribution of geological phenomena such as seismicity, volcanism, continental drift, and mountain building in terms of the formation, destruction, movement, and interaction of the earth's lithospheric plates.
2. (used with a sing. or pl. verb) The dynamics of plate movement.

plate′-tec·ton′ic adj.

plate tectonics

n
(Geological Science) (functioning as singular) geology the study of the structure of the earth's crust and mantle with reference to the theory that the earth's lithosphere is divided into large rigid blocks (plates) that are floating on semifluid rock and are thus able to interact with each other at their boundaries, and to the associated theories of continental drift and seafloor spreading

plate′ tecton′ics


n.
a geologic theory that describes the earth's crust as divided into a number of rigid plates, movement of which accounts for such phenomena as continental drift and the distribution of earthquakes.
[1965–70]
plate′-tecton′ic, adj.

plate tectonics

In geology, a theory that the Earth's lithosphere (crust and upper mantle) is divided into a number of large, plate-like sections that move as distinct masses. See Notes at fault, Gondwanaland, See more at tectonic boundary.
Did You Know? Have you ever noticed that the Earth's continents seem to fit together like pieces of a puzzle? This observation is what led the German meteorologist Alfred Wegener to propose the theory of continental drift in 1915. Since rocks and fossils were found to match up in parts of different continents, it seemed that they must have once been joined, but no one could explain how such large landmasses could move so far apart. This problem was not solved until the 1960s, when the theory of plate tectonics was proposed. According to this theory, the continents move apart by riding piggyback on plates—huge slabs of the Earth's lithosphere—that are much larger than the continents themselves. The plates move like parts of a conveyor belt powered by huge convection currents of molten rock that many geologists believe is heated by the decay of radioactive elements deep within the Earth. Although they only move a few inches per year, over hundreds of millions of years the continents are carried thousands of miles. Along their boundaries, the plates crumple, scrape, or pull apart from one another, giving rise to volcanoes and earthquakes and creating and destroying rock on the ever-changing surface of the planet.

plate tectonics


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The study of how lithospheric plates move around.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.plate tectonics - the branch of geology studying the folding and faulting of the earth's crust
geomorphology, morphology - the branch of geology that studies the characteristics and configuration and evolution of rocks and land forms
Pangaea, Pangea - (plate tectonics) a hypothetical continent including all the landmass of the earth prior to the Triassic period when it split into Laurasia and Gondwanaland
References in periodicals archive ?
When subject to changing temperature and pressure conditions at plate boundaries or elsewhere, these rocks do not react until exposed to externally derived fluids.
They did field work together and shared their international research on earthquakes that occur along tectonic plate boundaries, which is the case with Alaska, situated at the meeting point of the Pacific and North American tectonic plates.
Volcanism away from plate boundaries has also been explained as mantle plumes.
Subduction zones are where plate boundaries meet and when one plate sinks beneath the other, going into Earth's interior.
Going far beyond simply revising rupture occurrence probabilities in the existing model, AIR's updated model reflects a new understanding of the complex network of plate boundaries and crustal faults that underlie the Japanese archipelago," said Guin.
Several relevant tectonic elements, plate boundaries and active volcanoes, provide a context for the seismicity presented on the main map.
Dr Baptie, head of seismology at the British Geological Survey, said: "We're still affected by the plate motions and the forces that build up at the plate boundaries.
The report said that the faults in the plate boundaries of the subduction zones make them likely to be prone to rupture, generating massive earthquakes at temperatures between 150 and 450AC.
The UK is still being squeezed by the motion of the Earth's tectonic plates despite being far from plate boundaries.
At the moment, Wales and the whole UK is far away from any plate boundaries, from any location where plates come together or go apart, so that makes the chance of getting volcanic eruptions almost zero.
These areas, because they are so close to plate boundaries, are more likely to be hit by quakes when plates start moving as the earth tries to release heat.
At the same time, Inzai is farther away from active fault-lines and tectonic plate boundaries than Tokyo and thus meets Japan FISC (The Center for Financial Industry Information Systems) guidelines as a business continuity planning (BCP) site for companies with a primary data center in Tokyo.