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Plate tectonics  is a theory of geology. It has been developed to explain large scale motions of the Earth‘s lithosphere. This theory builds on older ideas of continental drift and seafloor spreading.
Dissipation of heat from the mantle is the original source of energy driving plate tectonics. Exactly how this works is still a matter of debate. The driving forces of plate motion continue to be active subjects of on-going research.
The outermost part of the Earth’s interior is made up of two layers. The lithosphere, above, includes the crust and the rigid uppermost part of the mantle.
Below the lithosphere is the asthenosphere. Although solid, the asthenosphere can flow like a liquid on long time scales. Large convection currents in the asthenosphere transfer heat to the surface, where plumes of less dense magma break apart the plates at the spreading centers. The deeper mantle below the asthenosphere is more rigid again. This is caused by extremely high pressure.
Thickness of plates
Ocean lithosphere varies in thickness. Because it is formed at mid-ocean ridgesand spreads outwards, it gets thicker as it moves further away from the mid-ocean ridge. Typically, the thickness varies from about 6 kilometres (3.7 mi) thick at mid-ocean ridges to greater than 100 kilometres (62 mi) at subduction zones.
Continental lithosphere is typically about 200 kilometres (120 mi) thick, though this also varies considerably between basins/ˈbeɪsn/, mountain ranges, and stable cratonic interiors of continents. The two types of crust also differ in thickness, with continental crust being considerably thicker than oceanic: 35 kilometres /ˈkɪləmiːtər/ (22 mi) vs. 6 kilometres (3.7 mi).
Movement of plates
The lithosphere consists of tectonic plates. There are eight major and many minor plates. The lithospheric plates ride on the asthenosphere. These plates move at one of three types of plate boundaries.
- 1–4 centimetres (0.39–1.57 in) per year (Mid-Atlantic Ridge). This is as fast as fingernails grow.
- 10 centimetres (3.9 in) per year (Nazca Plate)(or Nasca /ˈnɑs kɑ, -kə/. This is as fast as hair grows.
- together = mountains; volcanoes. The ‘Andes/ˈændiːz/ mountain range in South America and the Japanese island arc are examples. Also the Pacific Ring of Fire VÀNH ĐAI LỬA THÁI BÌNH DƯƠNG.
- away = earthquakes, trenches. The Mid-ocean ridges and Africa‘s Great Rift Valley are examples.
- side to side = earthquakes. The San Andreas Fault /’sæn æn.’dreɪ.əs ”fɔːlt/ in California is an example of a transform boundary. New Zealand is another, more complex, example.
Depending on how they are defined, there are usually seven or eight major plates:
- ‘African Plate /ˈæfrɪkən/
- Antarctic Plate
- Indo-Australian Plate, sometimes subdivided into:
- Indian Plate
- Australian Plate /ɔːˈstreɪ liən/
- Eurasian Plate. Eu.’ra.sian /juˈreɪʒn/
- North American Plate /əˈmerɪkən/
- South American Plate
- Pacific Plate /pəˈsɪfɪk/
tec•’ton•ic /tekˈtɑːnɪk/ adjective word origin mid 17th cent. (originally relating to building or construction): via late Latin from Greek tektonikos, from tektōn ‘carpenter THỢ MỘC, builder’. [only before noun] (geology) connected with the structure of the earth’s surface
ˌplate tecˈtonics noun [uncountable] (geology) the movements of the large sheets of rock (called plates) that form the earth’s surface; the scientific study of these movements
the vast span of geological time (= the whole of time since the earth began)
‘li.tho.sphere /ˈlɪθəsfɪr/ noun [singular] (geology) the layer of rock that forms the outer part of the earth
li’tho.gra.phy THẠCH QUYỂN/lɪˈθɑːɡrəfi/ noun word origin Lithographie (from litho- ‘relating to stone’ + -graphy). (also informal litho /ˈlaɪθoʊ/) [uncountable] the process of printing from a smooth surface, for example a metal plate, that has been specially prepared so that ink only sticks to the design to be printed litho•’graph•ic /ˌlɪθəˈɡræfɪk/ adjective
as·’then·o·sphere QUYỂN MỀM /æsˈθɛn əˌsfɪr/ Word Origin ( ) asthenia ) + -o- + -sphere. noun, Geology. 1. the region below the lithosphere, variously estimated as being from fifty to several hundred miles (eighty-five to several hundred kilometers) thick, in which the rock is less rigid than that above and below but rigid enough to transmit transverse seismic waves.
‘seis•mic /ˈsaɪ z mɪk/ ĐỊA CHẤN adjective word origin from Greek seismos ‘earthquake’ (from seien ‘to shake’) + -ic.[only before noun] 1 connected with or caused by earthquakes. seismic waves SÓNG ĐỊA CHẤN. 2 having a very great effect; of very great size. a seismic shift in the political process.
‘seis•mo•graph /ˈsaɪzməɡræf/ noun MÁY GHI ĐỊA CHẤN an instrument that measures and records information about earthquakes. seis•’mol•ogy /saɪzˈmɑːlədʒi/ noun [uncountable] the scientific study of earthquakes. seis•mo•’logic•al /ˌsaɪzməˈlɑːdʒɪkl/ adjective the National Seismological Institute. seis•’molo•gist /ˌsaɪzməˈlɑːdʒɪst/ noun.
o.ce.’a.nic /ˌoʊʃiˈænɪk/ adjective [usually before noun] (technical)connected with the ocean. word origin: from Greek ōkeanos ‘great stream encircling the earth’s disc’. “The ocean” originally referred to the whole body of water thought to encompass the earth’s single land mass.
‘Medi•ter”ra•nean /ˌmedɪtəˈreɪniən/ from Latin mediterraneus ‘inland’ (from medius ‘middle’ + terra ‘land’) + -an.
Pan’gae.a or Pan’ge.a (pronunciation: /pænˈdʒiːə/) TOÀN LỤC ĐỊA word origin early 20th cent.: from pan- ‘all’ + Greek gaia ‘earth’. was a ‘supercontinent that existed during the late Pa.le.o.’zo.ic /ˌpæliəˈzoʊɪk, ˌpeɪ-/and early Mesozoic eras. It assembled from earlier continental units approximately 335 million years ago, and it began to break apart about 175 million years ago. In contrast to the present Earth and its distribution of continental mass, much of Pangaea was in the southern hemisphere and surrounded by a superocean, Panthalassa. Pangaea was the most recent supercontinent to have existed and the first to be reconstructed by geologists.
Pal‧ae‧o‧’zo‧ic, Pale.o.’zo.ic /ˌpæliəˈzoʊɪk, ˌpeɪ-/ adjective: belonging or relating to the period of time in the Earth’s history, from about 570 million years ago to about 245 million years ago, when fish, insects, reptiles and some plants first started to exist → mesozoic. Origin: + +
A ‘continent /ˈkɑːntɪnənt/ CHÂU LỤC=LỤC ĐỊA=ĐẠI LỤC is a large area of the land on Earth that is joined together. In general it is agreed there are seven continents: ‘Africa /ˈæfrɪkə/ CHÂU PHI, Antarctica /ænˈtɑːrktɪkə/ CHÂU NAM CỰC, Asia /ˈeɪʒə/ CHÂU Á, Europe /ˈjʊrəp/CHÂU ÂU, North America CHÂU BẮC MỸ, Austra’lasia /ˌɔːstrəˈleɪʒə/ CHÂU ÚC or O.ce.’a.ni.a/ˌoʊʃiˈɑːniə/ CHÂU ĐẠI DƯƠNG, and South America CHÂU NAM MỸ.
Adjectives, noun person: ‘African/ˈæfrɪkən/, An.’tarc.tic/ænˈtɑːrktɪk/, ‘A.sian /ˈeɪʒn/, Euro•’pean /ˌjʊrəˈpiːən/, A’merican /əˈmerɪkən/, Aus.tra.’la.sian /ˌɔːstrəˈleɪʒə/, O.ce.’a.ni.an /ˌoʊʃiˈɑːniə/.
There are several ways of distinguishing the continents:
|Africa||Eurasia /jʊˈreɪʒə/||North America||South America||Antarctica||Australia|
|Africa||Europe||Asia||North America||South America||Antarctica||Australia|
|Các kiểu phân chia|
|7 châu lục
|Bắc Mỹ||Nam Mỹ||Châu Nam Cực||Châu Phi||Châu Âu||Châu Á||Châu Đại Dương|
|6 châu lục
|Bắc Mỹ||Nam Mỹ||Châu Nam Cực||Châu Phi||Đại lục Á Âu||Châu Úc|
|5 châu lục
|Châu Mỹ||(không tính)||Châu Phi||Châu Âu||Châu Á||Châu Đại Dương|
Pangaea or Pangea (/pænˈdʒiːə/) was a supercontinent that existed during the late Paleozoic /ˌpeɪliəˈzəʊɪk/ and early Mesozoic /ˌmezoʊˈzəʊɪk/eras. It was a very large area of land that existed as the only land on Earth about 300–225 million years ago, before it broke apart to form two large land masses, called Laurasia and Gondwanaland. These later broke apart to form the modern continents. In contrast to the present Earth and its distribution of continental mass, much of Pangaea was in the southern hemisphere and surrounded by a superocean, Panthalassa. The name “Pangaea/Pangea” is derived from Ancient Greek pan (πᾶν, “all, entire, whole”) and Gaia(Γαῖα, “Mother Earth, land”).
Panthalassa Greek πᾶν “all” and θάλασσα “sea” /θəˈlæs ə/), was the superocean that surrounded the supercontinent Pangaea. During the Paleozoic—Mesozoic transition c. 250 Ma it occupied almost 70% of Earth’s surface. Its ocean-floor has completely disappeared because of the continuous subduction along the continental margins on its cir’cumference. Panthalassa is also referred to as the Paleo-Pacific (“old Pacific”) or Proto-Pacific /ˈproʊtoʊ/ because the Pacific Ocean developed from its centre in the Mesozoic to the present., also known as the Pantha’lassic or Pantha’lassan Ocean, (from
Gond.’wa.na.land (ɡɒndˈwɑːnəˌlænd ) or Gondwana. Word origin: C19: from Gondwana region in central north India, where the rock series was originally found.