plate tectonic theory……. why alfred wegener thought of it……
Post on 20-Dec-2015
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Plate Tectonic Theory…….
Why Alfred Wegener thought of it……
Continental Fit……
Glacial Deposits……
Matching Geology
Matching fossils
Alfred Wegener needed a mechanism to move the continents……….
Sea Floor Spreading
Discovery of mid-oceanic ridge……
Symmetric magnetic anomalies adjacent to mid-ocean ridge axis…..
Figure A-5a and b
Paleomagnetism – magnetic signature locked in rocks
Magnetic Reversals
Age of ocean crust……
Figure 4-5
Global pattern of earthquakes
Figure 9.14
Global pattern of volcanoes – Ring of Fire