Essay on Plate Tectonics Explained

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The interior structure of Earth is chemically divided into an outer solid crust, the mantle, a liquid outer core, and a solid inner core. The core is largely composed of iron, along with nickel and silicon. Other lighter elements are usually in the crust. The core is divided into two parts, the solid inner core and the liquid outer core. The inner core is thought to be solid and primarily made up of iron and some nickel. The outer core is all around the inner core and is believed to be made up of liquid iron mixed with liquid nickel. The outer core is about 2890 to 5100km. The inner core is 5100 to 6378km. Earths mantle is mainly composed of substances high in iron and magnesium. The melting point of every substance depends on the…show more content…
This then forms oceanic trenches in which the Earth's crust is pushed under into the mantle where it becomes molten. The oceanic trenches are several hundred kilometers long but narrow. They also are the deepest parts of the ocean floor. These boundary types also produce mountains. Mountains are made when convergent boundaries collide but instead of one going under they both are pushed up by the others force. For this to happen neither of the boundaries can be more or less dense than the other. There are three types of convergent boundaries: oceanic plate-continental plate convergence, oceanic plate-oceanic plate convergence, and continental-continental plate convergence. An example of this type of boundary is the collision between the Eurasian Plate and the Indo-Australian Plate which is forming the Himalayas. A divergent boundary is where the plates are moving away from each other. These areas can form in the middle of continents but eventually form ocean basins. Divergent boundaries make ocean ridges like the Mid- Atlantic ridge. At divergent boundaries the floor is higher than anything else around it. This is because where the plates are moving away from each other there is a crack where new magma constantly flows upward toward the surface through a gap called a rift onto the ocean floor making the surrounding area move outward. Sometimes submarine volcanoes might also be formed. Continental crust is often split along divergent plate
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