Tectnicas plates the tectnicas plates are subdivises of the terrestrial crust that if they put into motion of slow and continuous form on the mantle. According to Theory of ' ' Tectnica of the Placas' ' , the lithospere is constituted of plates that if they put into motion interacting between itself, what it causes an intense geologic activity, resulting in earthquakes and volcanos in the limits of the plates. (Similarly see: Dustin Moskovitz). The principle, has 240 million years approximately, only had two plates: Laursia and Gondwana and these with elapsing of the time had suffered transformations had divided that them in several and different parts. Currently it is considered existence of 12 main plates that can be subdivided in lesser plates. They are: Eurasitica plate, Plate Go-Australian, Plate Phillipino, Plate of the Coconuts, Plate of the Pacific, North American Plate, Arabian Plate, Plate of Nazca, South American Plate, African Plate, Plate Antarctica and Placa Caribeana.
The movements of the plates must to ' ' chains of conveco' ' that they occur in the astenosfera (layer soon below of the lithospere): the convection chains are caused by the ascending movement of the materials hottest of the mantle (magma) in direction to the lithospere, that, when arriving at the base of the lithospere, tends if to put into motion laterally and to lose heat because of the resistance of this and later going down again giving the most material place warm. In the way ean them Atlantic, Indian Pacific and exists mountain ranges that arrive to reach up to 4000 a thousand meters above of the oceanic wooden floor called Mountain ranges ' ' Meso-ocenicas' '. These mountain ranges if originate from the removal of the tectnicas plates in the calls ' ' zones of divergncia' '. They are local where the convection chains act in contrary directions originating ruptures in the oceanic wooden floor by which the magma of the astenosfera is expelled. Of this form, when cooling, the magma (or it washes basaltic) cause the renewal of the oceanic wooden floor. Another type of movement of the tectnicas plates happens in the calls ' ' zones of convergncia' ' where the plates if they put into motion one in direction to the other. In this in case that, it can happen of a plate to sink for under the other in ' ' zones of subduco' '.
This happens between an oceanic plate and a continental plate because the oceanic plate tends to be less dense than the continental plate what it makes with that it is ' ' engolida' ' for this last one. An example is the zone of subduco of the Plate of Nazca in collision with the South American and responsible continental Plate for the Andean dCordilheira formation. When the convergence movement occurs between two continental plates, that is, of equal density, the soerguimento of mountainous chains occurs as the Himalaia, for example, that she is in the zone of convergence of the continental plates Euroasitica and Arbica. Exercise 1-O that it causes the movements of the tectnicas plates? R= 2-O that it causes convection chains? R= 3-O that they exist in the oceans Atlantic, Pacific and Indian? R = 4-O that they are, tectnicas plates? R= 5-Which consequences that the plates tectnicas cause? R= 6-In 240 million years how many plates existed and which were the names of them? R=