Geophysics is the application of the principles of physics to studies of the earth's interior. Canadian geophysicists are world leaders in developing sophisticated new technologies in the search for mineral deposits and in explaining the movement of continents and evolution of the oceans by plate tectonics.
Geophysicists employ gravitational, electromagnetic, and seismic methods to study the earth.
Hundreds of years ago, Sir Isaac Newton deduced that all particles of matter exert a gravitational attraction upon each other. He could not have envisioned that geophysicists would today use this discovery to make detailed maps of the variation in the gravitational attraction at the surface of the earth. The same principles are also used to determine the three-dimensional structure of the earth's crust, the depths of the roots of mountains, etc. We know that the earth, with its North and South magnetic poles, behaves like a dipole magnet. As rocks are formed, magnetic domains in the materials that will form the rock align themselves, like tiny compasses, to the earth's magnetic field of the time.