Tuesday, September 30, 2008

Two-Plate Countries

The great majority of the countries on this planet lie completely upon their respective Continent's plate. However, there are some that straddle two tectonic plates and are thus especially susceptible to earthquakes.

Iceland is the most obvious example; rising above the mid Atlantic Ridge, the western half of this island nation lies on the North American Plate while the eastern portion is part of the Eurasian Plate. While almost all of the continental U.S. and Mexico occupy the North American Plate, Southern California and the Baja are inching slowly to the northwest atop the Pacific Plate. Easternmost Russia and northern Japan lie on the North American Plate while the remainder of these countries sit on the Eurasian Plate. New Zealand also straddles two plates; its North Island and the northwest portion of its South Island lie on the Australian Plate but the rest of the South Island occupies the Pacific Plate.

But the most complex assembly of countries and tectonic plates is in the Middle East. Here, Lebanon and Syria straddle the African and Arabian Plates while Turkey and Iran, primarily on the Eurasian Plate, also overlap portions of the Arabian Plate. The latter Plate has been moving northward for the past 20 million years, crunching into the Eurasian Plate, pushing up mountain ranges and triggering massive earthquakes.