describe the chemical and physical properties of each of Earth’s layers
THE PHYSICAL & CHEMICAL PROPERTIES OF LAYERS
LITHOSPHERE: includes the crust and the uppermost part of the mantle. The cool, solid lithosphere floats on top of the asthenosphere.
Scientists believe that below the lithosphere is a relatively narrow, mobile zone in the mantle called the asthenosphere (from asthenes, Greek for weak). This zone is composed of hot, semi-solid material, which can soften and flow after being subjected to high temperature and pressure over geologic time. The rigid lithosphere is thought to “float” or move about on the slowly flowing asthenosphere.
This layer is solid and rigid compared to the asthenosphere because the temperature is not high enough to overcome the high pressure. high density, ultramafic silicate rock which can flow when subjected to long duration stresses. The mantle is over 2900 km thick and makes up over 80% of the volume of the Earth. The mantle is not molten!
The outer core is liquid. The circulation of its molten iron is thought to be the source of earth’s magnetic field.
There is very high pressure in the inner core. As a result, even though the temperature is extremely high, the inner core is solid. iron and nickel, liquid outer region with a solid center. The core is just over half the diameter of the Earth.