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How Tectonic Plates Take the Plunge

Mt Etna

The formation of Europe’s largest volcano, Mt Etna, cannot be explained directly by the theory of plate tectonics. Credit: Sebastien Litrico

By Wouter P. Schellart

New evidence shows that the speed of the Earth’s tectonic plates and their boundaries, as well as the formation and destruction of mountain ranges, is controlled by the size of plate boundaries.

Wouter P. Schellart is an Australian Research Council QE II Fellow and a Monash Fellow with the School of Geosciences at Monash University.

The full text of this article can be purchased from Informit.

In the 16th century a Dutch cartographer named Abraham Ortelius noticed the jigsaw fit between the east coast of the Americas and the west coast of Europe and Africa. He argued that the continents were once joined together and subsequently separated.

This idea was largely forgotten in the following centuries, although several others proposed a similar jigsaw fit. It wasn’t until 1912, when the German geophysicist Alfred Wegener proposed his theory of continental drift, that a wealth of geological data was presented to support the hypothesis of a jigsaw fit of the continents and of the former existence of an ancient supercontinent, which Wegener called Pangea (meaning “all Earth”). Wegener argued that the supercontinent was subsequently destroyed when the individual continental masses, including Eurasia, Africa, North America, South America, India, Antarctica and Australia, separated from each other due to divergent motion between them. Wegener compiled much of the pre-drift geological data to show that the continuity of older structures, rock formations, glacial deposits, fossil floras and faunas located along the shorelines of many continents could be explained with a pre-drift reconstruction of Pangea.

The new theory of continental drift was mostly received with disbelief, since it broke away from the accepted view of a static Earth, because many...

The full text of this article can be purchased from Informit.