Earth Structure
The Earth is comprised is of three layers:
The Core
The core comprises of dense rocks, especially of iron and nickel alloys. The inner core is solid and the outer core is liquid. The outer core is where the Earth’s magnetic fields originate, due to electrical currents flowing in the metallic core. Fluid moves due to convection currents. It is thought there is a radioactive decay happening in the core which powers the convection currents.
The inner core is 1100km deep. The outer core is 2400km deep
The Mantle
The mantle is less dense than the core as the rocks are comprised of lighter elements such as silicon and oxygen with varying densities depending on the proximity to the core.
The junction between Core and Mantel is known as the Gutenberg Discontinuity.
The Crust
The junction between the Mantle and Crust is called the Mohorovičić or Moho discontinuity.
The density of the crustal rocks is lower than the core and mantle because of lighter elements such as oxygen, silicon, aluminium, potassium and sodium. There is a large difference in the thickness of the crust depending on what is on the surface. It can range from only 5km thick below the oceans to up to 65km think below mountain ranges.
Lithosphere
The Lithosphere is the crust and the rigid upper part of the mantle forming a layer which is 80km thick; this is divided in to 12 larger plates and numerous smaller ones.
Asthenosphere
The asthenosphere is semi-molten material below the lithosphere on which the plates of the lithosphere ‘float’. The asthenosphere is several hundred kilometres thick.
The core comprises of dense rocks, especially of iron and nickel alloys. The inner core is solid and the outer core is liquid. The outer core is where the Earth’s magnetic fields originate, due to electrical currents flowing in the metallic core. Fluid moves due to convection currents. It is thought there is a radioactive decay happening in the core which powers the convection currents.
The inner core is 1100km deep. The outer core is 2400km deep
The Mantle
The mantle is less dense than the core as the rocks are comprised of lighter elements such as silicon and oxygen with varying densities depending on the proximity to the core.
The junction between Core and Mantel is known as the Gutenberg Discontinuity.
The Crust
The junction between the Mantle and Crust is called the Mohorovičić or Moho discontinuity.
The density of the crustal rocks is lower than the core and mantle because of lighter elements such as oxygen, silicon, aluminium, potassium and sodium. There is a large difference in the thickness of the crust depending on what is on the surface. It can range from only 5km thick below the oceans to up to 65km think below mountain ranges.
Lithosphere
The Lithosphere is the crust and the rigid upper part of the mantle forming a layer which is 80km thick; this is divided in to 12 larger plates and numerous smaller ones.
Asthenosphere
The asthenosphere is semi-molten material below the lithosphere on which the plates of the lithosphere ‘float’. The asthenosphere is several hundred kilometres thick.
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