What is the continental drift?
(Lansing State Journal, February 19, 1992)



Question submited by: M. Margeneau of Williamston  

Continental drift is a theory that maintains the continents are slowly moving toward or away from each other.  The theory was proposed by Alfred Wegener in 1915 to explain why similar animals are found on different continents.  (Camels are found in Africa and Asia, for instance.) Wegener noticed continents could be fit together, much like pieces of a puzzle.

Wegener suggested that more than 200 million years ago the continents formed a single supercontinent, surrounded by ocean.

The main difficulty with Wegener’s theory was that it contained no explanation of how entire continents could move.  In 1968, the theory of tectonic plates attempted to solve this problem.  The tectonic plate theory of tectonic plates attempted to solve this problem.  The tectonic plate theory states that the main elements of the Earth’s surface are not the continents, but huge pieces of rock spanning the surface.  These pieces of rock are covered by continents and ocean.  Scientists today believe that there are six main plates, and a number of other smaller plates.

The motion of tectonic plates can explain the formation of mountain chains, the occurrence of earthquakes and the creation of new volcanic islands.

Although the theory of tectonic plates has given much support to Wegener’s idea of continental drift, many questions remain unanswered.


[ Back to Ask Science Theatre | Back to Ask Science Theatre Date Index ]
Back to MSU Science Theatre Home Page