Advanced Search

Answer:

In a sense, yes. You probably know that the Earth is stratified; a section is pictured here. In radius it is composed of layers having different chemical composition and different physical properties. The crust of the Earth has some permanent magnetization, and the core of the Earth, the outer part of which is liquid iron and the inner of which is solid iron, generates its own magnetic field, sustaining the main part of the field we measure at the surface. So we could say that the Earth is, therefore, a ‘magnet’. But there is no giant bar magnet near the Earth’s center, despite the depictions you may have seen in elementary textbooks on geology and geophysics. Permanent magnetization cannot occur at high temperatures, like temperatures above 650 degrees centigrade or so, when the thermal motion of atoms becomes sufficiently vigorous to destroy the ordered orientations needed to establish permanent magnetization. The core of the Earth has a temperature of several thousand degrees, and therefore it is not permanently magnetized.

FAQ Home