Here is the Earth's crust in the middle layer, called the "mantle", the thickness of about 2865 kilometers, the main rock-forming material from the dense composition, which is the Earth's interior volume of the largest and the greatest level of quality. Mantle can be divided into two layers of the upper mantle and lower mantle. Upper mantle at the top there is a slowing down of seismic wave propagation velocity layer (Moho), lithosphere (crust and upper lithospheric mantle at the top refers to) the following known as the asthenosphere (Asthenosphere), speculated that asthenosphere is due to radioactive elements a large number of concentration, transformation heat, so that high-temperature softening of rock, and caused partial melting is very likely that magma (Magma) originated. Than asthenosphere mantle is an integral part of the lithosphere. Lower mantle temperature, pressure and density have increased plasticity of the material was solid. Thickness of about 2900 kilometers.
