4 ms·
It isn't just a theoretical supposition, I believe we measure alignment of magnetic fields in igneous rocks and the 'almost always' comes from that, the current
by inflatableDodo 7y ago
It isn't just a theoretical supposition, I believe we measure alignment of magnetic fields in igneous rocks and the 'almost always' comes from that, the current field of the earth being fixed in the rock when it solidifies.