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Intro to Plate Tectonics
Plate tectonics is the theory that Earth's outer layer is made up of plates, which have moved throughout Earth's history. The theory also explains why the land was formed in the shape that it is and the how certain surface features were formed.
225 million years ago all the major continents formed one giant supercontinent, called Pangaea. Since then, through plate tectonics the continents have separted to form the land masses we know today.
Convection currents within the Earth's mantle and moves the plates, creating movemet of about 6 inches a year that also causes volcanoes and earthquakes to occur.
The movement caused by plate tectonic activity takes place at four types of boundaries: divergent boundaries, where new crust is formed; convergent boundaries, where crust is consumed; collisional boundaries, where two land masses collide; and transform boundaries, where two plates slide against each other.
Plate tectonics is the theory that Earth's outer layer is made up of plates, which have moved throughout Earth's history. The theory also explains why the land was formed in the shape that it is and the how certain surface features were formed.
225 million years ago all the major continents formed one giant supercontinent, called Pangaea. Since then, through plate tectonics the continents have separted to form the land masses we know today.
Convection currents within the Earth's mantle and moves the plates, creating movemet of about 6 inches a year that also causes volcanoes and earthquakes to occur.
The movement caused by plate tectonic activity takes place at four types of boundaries: divergent boundaries, where new crust is formed; convergent boundaries, where crust is consumed; collisional boundaries, where two land masses collide; and transform boundaries, where two plates slide against each other.
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Convection Currents
The mantle is made of much denser, thicker material, because of this the plates "float" on it like oil floats on water.
Convection currents are caused by the very hot material at the deepest part of the mantle rising, then cooling, sinking again and then heating, rising and repeating the cycle over and over. When the convection currents flow in the mantle they also move the crust. The crust gets a free ride with these currents. the crust can move between 2-15 cm each year due to the currents I the mantle. This crust movement is the catalyst for the earthquakes and volcanos that occur on the plate boundaries.
The mantle is made of much denser, thicker material, because of this the plates "float" on it like oil floats on water.
Convection currents are caused by the very hot material at the deepest part of the mantle rising, then cooling, sinking again and then heating, rising and repeating the cycle over and over. When the convection currents flow in the mantle they also move the crust. The crust gets a free ride with these currents. the crust can move between 2-15 cm each year due to the currents I the mantle. This crust movement is the catalyst for the earthquakes and volcanos that occur on the plate boundaries.