Plate Tectonics = Has undergone lots of testing = A working theory
B. Historical Development
1. Alfred Wegener - 1915 => continents have changed position on the Earth’s surface through time.
=> Continental Drift
- Pangea
300 m.y. old
Supercontinent
2. Wegener’s evidence:
a. Jigsaw fit of the continent’s edges
b. Paleoclimate indicators at wrong latitudes
- glacial deposits, reefs, coal, etc.
c. Fossil Evidence => fossil species match between continents separated by oceans
3. Problems with Wegener’s theory:
=> an inadequate mechanism - centrifugal force
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How to explain the oceans