Dishwasher/
2006-09-20 15:33:45
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answer #1
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answered by Tall Guy 3
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The theory of plate tectonics formulated during the late 1960s is now almost universally accepted and has had a major impact on the development of the earth sciences. Its adoption represents a true scientific revolution, analogous in its consequences to the Bohr atomic models in physics or the discovery of the genetic code in biology. Incorporating the much older idea of continental drift, the theory of plate tectonics has made the study of the Earth more difficult by doing away with the notion of fixed continents, but it has at the same time provided the means of reconstructing the past geography of continents and oceans.
The requirement that plates are not internally deformed has become one of the postulates of plate tectonics. It is not totally supported by evidence, but it appears to be a reasonable approximation of what actually happens in most cases and is needed to permit the mathematical reconstruction of past plate configurations. The joint pole of rotation of two plates can be determined from their transform boundaries and from their divergent plate boundaries usually by means of magnetic anomalies. Because all plates form a closed system, all movements can be defined by dealing with them two at a time. It is conceivable that the entire lithosphere might slide around over the asthenosphere like a loose skin, altering the positions of all plates with respect to the spin axis of the earth and the equator. To determine the true geographic positions of the plates in the past which is so important in paleoclimatology and paleoceanography, investigators have to define their relative motions not to each other but rather to this independent frame of reference. Another method of determining absolute plate movements relies on the fact that the equatorial waters of the ocean are and always have been very fertile. The high biological productivity yields an enormous quantity of calcareolls microfossils, which like a gigantic natural chalk line, marks a narrow equatorial zone. The displacement of the equatorial deposits over time, traced by means of deep-sea drill cores, enables investigators to determine the direction and rate of plate movement. The development of the satellite and the Global Positioning Systems have enabled scientists to measure with some degree of accuracy these plate movements, and these data are also used to determine by extrapolation the past positions of the plates. The GPS measurements are most cost effective and yield greater quantities of reliable data. These GPS data were not available until this decade.
2006-09-20 15:32:29
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answer #2
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answered by Anonymous
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Mid-Atlantic Ridge, San Andreas Fault, The Himalayas, The Ring of Fire.
2006-09-20 15:30:36
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answer #3
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answered by Rinoa 3
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San Andreas Fault, also go to Alaska, there is a lot of activity there
2006-09-20 15:27:55
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answer #4
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answered by Mr MOJO123 2
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You can find maps on the web. Look up techtonic plate.
2006-09-20 15:27:47
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answer #5
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answered by keith 2
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any were there are constent earthquakes there is normally evidence that has been found so you look up areas near tectonic plates
2006-09-20 15:29:54
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answer #6
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answered by Anonymous
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Here is a good one: pubs.usgs.gov/gip/dynamic/understanding.html Good luck!
2006-09-20 15:29:08
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answer #7
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answered by Anonymous
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Any where you find a fault line.
2006-09-20 15:29:06
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answer #8
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answered by kirk878 2
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mountain ranges and ocean trenches
2006-09-20 15:28:21
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answer #9
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answered by tsihilin 3
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cafeteria?
2006-09-20 15:34:43
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answer #10
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answered by Anonymous
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