Continental Drift

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Continental Drift forms the argument that the earth's land mass use to be one large formation, Pangaea. However, it broke apart due to the weakness of the earth's crust and pieces of Pangaea broke away from one another (Pichon, 1968). This formed the separate continents we know today. The movement of plates are thought to result from convection currents in the mantle. Magma from the core of the earth expands and rises and as it cools near the earth's crust, sinks to the bottom once again. This cause circular currents within the earth's subsurface (Pichon, 1968).

(a) The initial hypothesis that continents had once formed a single land mass before breaking apart into their present location was proposed by Alfred Wegener (Hallam, 1973). Though he developed this hypothesis with the help of several other scientists, he was the first to use the phrase "continental drift" and to compose a fully developed and complete theory (Hallam, 1973). Though Wegener presented evidence for continental drift, he was unable to provide an explanation for the processes behind the movement and break up of Pangaea. Wegener proposed that the continents were pulled apart by centrifugal pseudoforce, cause by the earth's rotation and by astronomical precession (Hallam, 1973). These reasons were proven to be wrong.

Continental drift theory has been replaced by the science of plate tectonics, which provides an all-inclusive explanation of the process of continent movements, crust creation, subduction, the rock cycle, and many other lithological processes ...