The Theory of Plate Tectonics
Plate tectonics is the floor of the earth. It is what is under the sediment. The reason earth quakes occur is because the plates of the earth get pushed into each other overtime and they slide on top of each other causing the earth to shake. Volcanoes are also made from the plates of the earth causing to make lava rise up and make the volcano shake. Plate tectonics are responsible for most of earth’s geological features. As plates collide the crust crumbles and mountains change form. The shape and position of oceans and continents is also a result of plate movement although this process takes millions of years. Plate tectonics are the most important theory ever developed.
These are the 7 plates:
-Eaurasian plate
-African plate
-Indo-Autrailian plate
-Antarctic plate
-Pacific plate
-North American plate
-South American plate
These are the 7 plates:
-Eaurasian plate
-African plate
-Indo-Autrailian plate
-Antarctic plate
-Pacific plate
-North American plate
-South American plate
Convergent boundaryPlaces where plates crash or crunch together are called convergent boundaries. Plates only move a few centimeters each year, so collisions are very slow and last millions of years. Even though plate collisions take a long time, lots of interesting things happen. As the edge of the oceanic plate digs into Earth's hot interior, some of the rock in it melts. The melted rock rises up through the continental plate, causing more earthquakes on its way up, and forming volcanic eruptions where it finally reaches the surface. An example of this type of collision is found on the west coast of South America where the oceanic Nazca Plate is crashing into the continent of South America. The crash formed the Andes Mountains, the long string of volcanoes along the mountain crest, and the deep trench off the coast in the Pacific Ocean.
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Divergent boundaryPlaces where plates are coming apart are called divergent boundaries. When Earth's soft surface layer the lithosphere is pulled apart, it typically breaks along parallel faults that tilt slightly outward from each other. As the plates separate along the boundary, the block between the faults cracks and drops down into the soft, plastic interior the asthenosphere. Sinking forms a central valley called a rift. Magma moves upward to fill the cracks. In this way, new crust is formed along the boundary. Earthquakes occur along the faults, and volcanoes form where the magma reaches the surface.
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Transforming boundary
Places where plates slide past each other are called transform boundaries. Since the plates on either side of a transform boundary are sliding past each other and not tearing or crunching each other, transform boundaries have cool features found at convergent and divergent boundaries. Instead, transform boundaries are marked in some places by linear valleys along the boundary where rock has been ground up by the sliding. In other places, transform boundaries are marked by features like stream beds that have been split in half and the two halves have moved in opposite directions.