Plate Margins

The Earth's Structure

• The inner core is in the center and is the hottest part of the Earth. It is solid and made up of iron and nickel with temperatures of 5,500°C
• The outer core is the layer surrounding the inner core. It is a liquid layer, also made up of iron and nickel.
• The mantle is the thickest section of the Earth at approximately 2,900km. The mantle is made up of semi-molten rock called magma
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Theory of plate tectonics

• The crust is the solid rock layer upon which we live. It is either continental or oceanic. The earth's crust is broken into plates. Heat rising and falling inside the mantle creates convection currents generated by radioactive decay in the core. The convection currents move the plates. Where convection currents diverge near the Earth's crust, plates move apart.
• Where convection currents converge, plates move towards each other. The movement of plates, and the activity inside the Earth, is called the theory of plate tectonics.
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