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Drifting Continents Seventh Grade Quarter Three
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Inquiry Question Which coastlines of continents seem to match up like jigsaw-puzzle pieces?
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Europe Asia Africa South America North America Australia Antarctica
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Alfred Wegener 1880 - 1930 German meteorologist Proposed the theory of continental drift in 1912.
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Continental Drift The curiosity of Alfred Wegener led him to the hypothesis that Earth’s continents had moved. Wegener’s hypothesis was that all the continents were once joined together in a single landmass and have since drifted apart.
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Millions of Years Ago Today How could this have happened?
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Continental Drift Definition: The idea that the continents slowly moved over Earth’s surface.
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Pangaea Means “all lands.” According to Wegener, the continents were once all together to form this supercontinent. Existed about 300 million years ago.
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Pangaea Continued Over tens of millions of years, Pangaea began to break apart. The pieces slowly moved toward their present-day locations.
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How the continents moved http://www.noc.soton.ac.uk/gg/classroom@sea/general_science/plate_tectonics/cont_drift.html show me
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How in the world?! How would we be able to hypothesize the idea of Pangaea? What evidence would support the idea?
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Evidence of Continental Drift Wegener gathered evidence from different scientific fields to support his ideas about continental drift. He studied: land features, fossils, and evidence of climate change. Landforms
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Evidence From Land Features Mountains and other features on the continents provided evidence. Example: When you put together Africa and South America mountain ranges on both continents line up. Example: Coal fields from Europe line up with coal fields in North America.
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Rock/Land Features Evidence
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Evidence From Fossils Fossil: any trace of an ancient organism that has been preserved in rock. Fossils from an ancient plant have been found Africa, South America, Australia, India, and Antarctica. This convinced Wegener that Pangaea existed.
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Other Examples of Fossil Evidence: Fresh water reptile fossils found in places now separated by oceans. Neither reptile could have swum great distances across salt water. Must have lived on a single landmass that has since split apart.
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Fossil Evidence
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Evidence From Climate Towards the equator, climate is warmer Towards the poles, climate is colder Continents carry fossils and rocks Fossils from tropical plants were found on an island in the Arctic Ocean that are over 300 million years old. Must have been located close to the equator at one time per Wegener
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More Climate Evidence Geologists found evidence of cold weather in South Africa. Deep scratches in rocks showed that there were once continental glaciers there. So...During Pangaea South America must have been much closer to the South Pole and moved over the years.
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Climate/Glacier Evidence
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Wegener’s Hypothesis Rejected He could not provide a satisfactory explanation for the force that pushes or pulls the continents. So his hypothesis was rejected and further studied by geologists for many years.
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In Summary http://player.discoveryeducation.com/index.cfm?guidAsse tId=CC58E756-9311-4EA8-B7AF- F4D150C20950&blnFromSearch=1&productcode=US
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Pangaea Activity Show the progress of continental drift over the years using construction paper and stencils. Show the original Pangaea, how the continents look today, and then one time in between to show the movement of the continents over time. Summarize what happened and the proof.
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