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The structure of earth

From the outside the Earth can be divided largely into crust, mantle, out core and inner core and the crust can be divided into the ocean crust and the continental crust. The continental crust is formed of granite rocks, is approximately 35km thick and has a density of 2.7gr/cm3.

On the other hand the ocean crust encompasses a rock layer approximately 7km thick and constituted of whinstone or gabbro rock and is approximately 3.0gr/cm3 dense. Underneath the crust there is a chemically homogeneous mantle and the mantle thickness is 2885km and one of the largest masses inside the inner constituent unit. Also the out core is consisted of an iron and nickel combined element and the inner core which only consists of iron is situated at the center of the Earth. The out core possesses a flowing liquid character and the inner core that of a metallic solid. The boundary between the crust and the mantle is occupied by Mohorovicic discontinuity, between the mantle and the out core Gutenberg discontinuity and Lehmann discontinuity between the out core and inner core.
The structure of earth
The lithosphere is the highest area of the mantle and crust and makes a firm shell of the Earth. The lower part of the lithosphere is smooth for a section of approximately 670km and a tender asthenosphere is located. Beneath the asthenosphere to the out core section the mesosphere is located. Underneath the mesosphere the center of the core is situated the temperature is 7000K, and the pressure reaches 360 GPa. The center of the Earth is the hottest and the more towards the outside the more the temperature lowers and as a result convection current occurs. Above the comparatively weak asthenosphere the lithosphere moves due to the convection current from the mantle. Due to this movement mountain ranges are formed which make great basins. These also constitute the reason for earthquakes.