Paul giving a session

RAW4: Info — (Hara Level) Molten Core of the Earth

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Notes:

Molten Core

molten core The Earth is a sphere with a diameter of about 12,700 km. As we go deeper and deeper into the earth the temperature and pressure rises. The core temperature is believed to be 5000-6000°c.

The crust is very thin (average 20 km). This does not sound very thin but if you were to imagine the Earth as a football, the crust would be about ½ millimetre thick.

Notes (continued):

The thinnest parts are under the oceans (OCEANIC CRUST) and go to a depth of roughly 10 km. The thickest parts are the continents (CONTINENTAL CRUST) which extend down to 35 km on average. The continental crust in the Himalayas is some 75 km deep.

The mantle is the layer beneath the crust which extends about half way to the center. It is made of solid rock and behaves like an extremely viscous liquid.

The outer core is the layer beneath the mantle. It is made of liquid iron and nickel. Complex convection currents give rise to a dynamo effect which is believed to be responsible for the Earth's magnetic field.

The inner core is the bit in the middle. It is made of solid iron and nickel. It is believed to have solidified as a result of pressure-freezing, which occurs to most liquids under extreme pressure.