Lecture 24 - Lecture 24 PLATE TECTONICS (pg. 339-352) - the...

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Lecture 24 PLATE TECTONICS (pg. 339-352) --- the theory that landmasses, the continents, have been and are moving or "floating" atop the asthenosphere History of the theory: --- Alfred Wegener (1912) first scientist to suggest that continents were moving, and to supply some evidence for it * one landmass some 225 MYBP (Triassic Period) called Pangaea * broke-up into around 135 MYBP (Cretaceous Period) * evidence : similarities of fossils, climatic records, and geologic record between distant continents, esp. South America and Africa --- 1940-1960's, Atlantic ocean floor mapping * discovery of magnetic reversals, the magnetic alignment of charged particles (esp. Iron material) in the rock which exhibit a symmetrical pattern as you move away from the mid-oceanic ridge, the polarity, the orientation of positive(+) and negative(-) to the Poles of the Earth, change as you move away from the mid oceanic ridge because the rock cools/forms at different times --- 1960's, Hess & Dietz develop theory of
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This note was uploaded on 04/30/2008 for the course GEOG 1111 taught by Professor Hopkins during the Spring '08 term at University of Georgia Athens.

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Lecture 24 - Lecture 24 PLATE TECTONICS (pg. 339-352) - the...

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