Dedicated to the teaching of Earth Sciences   Prof. Sean Tvelia
Suffolk County Community College   Paleomagnetism and
Continental Drift  By the mid twentieth century enough evidence
had been amassed to begin openning the minds of many scientists
to the idea that the continents could have moved across the
surface of the Earth. But, armed with only circumstantial
evidence and conjecture, convincing the conservative scientific
majority would be nearly impossible. Proponents of Continental
Drift would need hard data and that data couldn't get much
harder than that found in the igneous rocks of the crust.
Igneous rocks are formed when molten rock (magma) cools and
allows the mineral components to crystallize. During this
cooling process iron-rich crystals that form in the liquid melt
are affected by the earth's magnetic field. Much like the needle
on a compass these crystals align themselves with the earth's
magnetic field and, when the magma cools, permantly record the
relative strength and direction of the magn