Cause of the Earth's magnetic field

[Alan Grayson]

Is the existence of the Earth's magnetic field a solved problem in geophysics? Assuming it's caused by a charged current of molten iron ions, 

even if the ions are created by the freeing of electrons due to thermal conditions (aka heat), wouldn't the released electrons, having an opposite

charge of the iron ions, result in an overall neutrally charged current, with the results cancelling out, to produce a net ZERO magnetic charge? TIA.

[smitra]

You need to study dynamo theory, see e.g. here:

http://farside.ph.utexas.edu/teaching/plasma/Plasmahtml/node70.html

Saibal