But because the magnetic field is caused by currents in moving liquid, it's not going to necessarily line up with the geographical north pole. It sloshes around so magnetic north moves around too, and from time to time it flips over completely so north becomes south. There is evidence for this in recent rocks - as they are laid down bit by bit, which way the magnetic field magnetised them was preserved. If you were able to see the magnetism, they'd look striped. The last time was around 780,000 years ago, though there was another brief one around 41,000 years ago.
There isn't really anything else that contributes in any significant way to the Earth's magnetic field. Continental drift contributes to magnetism in the crust moving around, but that's very tiny compared with that big dynamo churning around in the outer core.
If there wasn't a liquid core generating it, the Earth just wouldn't have a magnetic field this big at all. It would be like the Moon. The Moon has a very weak magnetic field caused entirely by magnetised rocks in the crust. It certainly doesn't have a magnetic north and south (so don't bother taking a magnetic compass there). We can conclude that if the Moon ever had a hot core, it must have cooled down a long time ago. Which is not surprising when it's smaller. The Earth is bigger and has kept its internal heat, or at least, enough to create the magnetic field.
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Morningfox say: True north is straight toward the North Pole, the axis of the Earth's spin.
Magnetic north is toward the magnetic north pole, along the curved lines of magnetic force. It moves, and is now at a location about 400 kilometers from the geographic North Pole.
The magnetic field comes the core, with deflections caused by the mantel and crust.
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Ndifor say: Magnetic north: the direction the north end of a compass needle points, corresponding to the direction of the Earth's magnetic field lines.