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Contents of 10.3 How does outer-core convection generate the magnetic field?

• The shape of Earth's magnetic field resembles that produced by a magnet. These lines of force indicate an origin deep within Earth, where temperatures are too high for permanently magnetized material to exist.
• The magnetic field must be continually generated by the geodynamo, a term that describes rapid convective motion of electrically conductive iron-rich liquid in the outer core.
• Complexities in outer core convection caused by electrical conductance through the inner core, interaction of magnets and viscosity, and transfer of mass or heat from the outer core to the mantle may account for the rapid fluctuations in strength and orientation of the magnetic field, as well as absolute reversals.

10.3 How does outer-core convection generate the magnetic field?