There are two kinds of plates of earth

 Converging plates of earth

 In many places around the world, the tectonic plates that make up the Earths crust, or outer layer, are slowly crunching together with enormous force.The Atlantic is getting wider, pushing the Americas further west. Yet the Earth is not getting any bigger because as the American plates crash into the Pacific plates, the thinner, denser ocean plates are driven down into the Earth’s hot mantle and are destroyed. 


 "The process of driving an ocean plate down into the Earth’s interior is called subduction.
 " Subduction creates deep ocean trenches typically 6-7 km deep at the point of collision. One of these, the Mariana Trench, could drown Mt Everest with 2 km to spare on top. As an ocean plate bends down into the Earth’s mantle, it cracks. The movement of these cracks sets off earthquakes originating up to 700 km down. These earthquake zones are called Benioff-Wadati zones after Hugo Benioff, who discovered them in the 1950s. As an ocean plate slides down, it melts and makes blobs of magma. This magma floats up towards the surface, punching its way through to create a line of volcanoes along the edge of the continental plate. If volcanoes in subduction zones emerge .in the sea, they form a curving line of volcanic islands called an island arc. 
Beyond this arc is the back-arc basin, an area of shallow sea that slowly fills up with sediments. As a subducting plate sinks, the continental plate scrapes sediments off the ocean plate and piles them in a great wedge. Between this wedge and the island arc there may be a fore-arc basin, which is a shallow sea that slowly fills with sediment. Where two continental plates collide, the plate splits into two layers: a lower layer of dense mantle rock and an upper layer of lighter crustal rock, which is too buoyant to be subducted. As the mantle rock goes down, the crustal rock peels off and crumples against the other to form fold mountains 
. This is a cross-section through the top 1000 km or so of the Earth’s surface. It shows a subduction zone, where an ocean plate is bent down beneath a continental plate.  

Tectonic plates of earth

 "The Earth’s surface is divided into slabs called tectonic plates." Each plate is a fragment of the Earth’s rigid outer layer, or lithosphere (see the lithosphere). There are 16 large plates and several smaller ones. Plates are approximately 100 km thick but can vary in thickness from 8 km to 200 km.

The biggest plate of earth 

Pacific plate

 The biggest plate is the Pacific plate, which underlies the whole of the Pacific Ocean. 
The Pacific Ocean represents half of the world’s ocean area. Tectonic plates are moving all the time - by about 10 cm a year. Over hundreds of millions of years they move vast distances. Some have moved halfway round the globe. 
The continents are embedded in the tops of the plates, so as the plates move the continents move with them. The Pacific plate is the only large plate with no part of a continent situated on it.lt represents more than one-third of the Earth’s surface area. The movement of tectonic plates accounts for many things, including the pattern of volcanic and earthquake activity around the world.

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