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Download Dec 2 Continental Drift (LT 1-2)
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September 30 Question: Why do scientists on p age think all the continents 6 were once connected? Notebooks: Katie & Brennan Timekeeper: Logan Write the following on the Goal Sheet in your notebook. October 3 Goal: I can explain the evidence for the Theory of Continental Drift (LT # 1-2) Rate your understanding of this topic at this moment, and how much effort you plan to give to class today. Plate Tectonics Learning Targets Indicator: Earth’s crust consists of major and minor tectonic plates that move relative to each other. Learning Targets: I can … 1. Explain how our understanding of plate tectonics has developed through the contributions of Alfred Wegener, Harry Hess, and Robert Dietz 2. 3. 4. 5. Explain 4 pieces of evidence for the theory of continental drift. Describe the process of seafloor spreading Explain at least three pieces of evidence for seafloor spreading Explain how evidence of polar wandering supports plate tectonics 6. Explain which layer of earth is divided into tectonic plates 7. Tell that the tectonic plates float on the asthenosphere 8. Identify and describe the geothermal movements that cause plate motion. Vocabulary: continental drift, seafloor spreading, convection, tectonic plate, Mesosaurus, Glossopteris, Pangaea, mantle, asthenosphere, lithosphere, magnetic field, trench, subduction, rift valley, midocean ridge, polar wandering, geothermal continents have slowly moved to their current locations. Alfred Wegener 1912 Pangaea all continents 200 million Mesosaurus South America not swim Africa ocean joined Glossopteris Africa India Australia South America Antarctica Glossopteris warm Arctic Spitsbergen Glacial glaciers Africa Australia ice south pole rocks similiar connected eastern U.S. Greenland western Europe rocks Africa joined Why didn't scientists accept the hypothesis of continental drift? Because it didn't explain HOW continents could move Theory of Continental Drift Proposed by Alfred Wegener in 1912 Theory of States that all land was once joined together in supercontinent called (Pangaea) that slowly drifted apart Scientists didn't believe continents could move, so theory wasn't accepted Evidence: Puzzlelike fit of the continents Theory of Rocks and mountains match up where continents would be joined Same fossils found on different continents that they couldn't travel between Climate fossils found in areas they couldn't survive evidence of glaciers found in warm areas Freshwater ponds and lakes; needed to breathe air from surface No; Ocean is salt water. Mesosaurus traveled to or lived in these areas when the continents were still joined together. Yes, since the Mesosaurus could not travel the ocean between these continents, it had to have lived in these areas when the continents were still joined. While more than one piece of evidence is needed to "prove a theory", the Mesosaurus does seem to support Continental Drift. The Mesosaurus could not swim between the two continents; it lived before humans; thus, a boat did not take it between the continents; it is highly unlikely that the same organism could have independently came into being in two different places. Consequently, the only way it could have ended up on both continents is if it traveled there while the continents were still joined.
