Tectonic plates are pieces of earth's crust and uppermost mantle,together referred to as the lithosphere.The plates are around 100 km (62 mi)thick and consist of two principal material:ocean -crust(also called sima from silicon magnesium) and continental crust (sial from silicon and aluminium).The composition of the two types of crust differs markedly,with basaltic rocks ("mafic")
dominating oceanic crust,while continental crust consists principally of lower density granitic rocks.
Geologists generally agree that the following tectonic plates exist on the 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 micro (or tertiary) plates.
Major plates :
dominating oceanic crust,while continental crust consists principally of lower density granitic rocks.
Geologists generally agree that the following tectonic plates exist on the 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 micro (or tertiary) plates.
Major plates :
These plates comprise the bulk of the continents and the pacific ocean.A major plate is any plate with an area greater than 20 million km.
Minor plates :
These smaller plates are often not shown on major plate maps,as the majority do not comprise significant land area.A minor plate is may is any plate with an area less than 20 million km but grater than 1 million km.
Micro plates :
These plates are often grouped with an adjacent major plate on a major plate map.A micro plate is less than the area of 1 million km.
Types of Tectonic Plates |
The center of the earth contain's high temperature is 6000 degree celsius it is 1000 times grater than in a previous experiments run from 20 years. Heat came from the inner core to earth surface at this time the tectonic plates are move's .when the plates are moved they collide with each other then Earthquake's,Tsunami's are formed and also volcanoes are blasted.
Heat comes from inner core of the earth |
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