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Continental Drift
Question | Answer |
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Continental Drift Theory | -The idea that Earth's continents moved apart from a single large continent called Pangaea |
Plate Tectonics | -The theory of plate tectonics says that Earth's outer layer is made up of large, moving pieces called plates -All of Earth's land and water sit on these plates -Under plates is a weaker layer of melted rock -The plates are moving over this weaker layer |
Glacial Evidence | -Glacial deposits formed 300 mya are found in Antarctica, Africa, South America, India, & Australia -Striations (scratches on rocks) show the ice flowing from the glaciers came from a single point -Evidence of glaciers is found in warm climates today |
Fossil Evidence | -Fossils of the same species found on separate continents & nowhere else -These plants & animals would have had to evolve independently or swim the distances -Fossils found didn't fit the climate (Palm tree leaf fossils in Alaska) |
Pangaea | -Super continent -began to break apart about 175 million years ago -there were probably other super continents before Pangaea -Earth's continents have been continually breaking apart and coming together |
Laurasia and Gondwanaland | -Gondwanaland separated from Laurasia between 200-180 million years ago -this roughly formed the northern and southern hemispheres |
Glossopteris | -Fossil Evidence -Plant that was found in all of the southern continents, showing they were once joined |
Mesosaruas | -Fossil Evidence -freshwater reptile |
Lystosaurus | -Fossil Evidence -Land reptile |
Cynognathus | -Fossil Evidence -a land reptile |
Continental Fit Evidence | -The continents, particularly South America & Africa together like puzzle pieces -Another piece of evidence that the continents were once joined |
Continents | -any of the world's main continuous expanses of land (North America, South America, Europe, Asia, Africa, Australia, Antarctica |
Alfred Wegener | -Proposed the Continental Drift Theory -Had a lot of fossil and rock evidence but his theory was rejected by most other scientists -not explain "how" the continents moved -In 1960s the theory was finally accepted & part of the Theory of Plate Tectonics |
Land-form/Rock Layers Evidence | -Appalachian Mountain matched well with those on the British Isles as well as other places -Similar types of rocks & similar ages of rocks were found on these 3 continents & other places -Coal fields in North America and Europe match up |