1. Continental Drift Text Book page numbers 92 - 96

2. Warm Up 1. What is the thickest layer of the Earth? 2. What is the thinnest layer of the Earth? 3. What happens to temperature as the depth within the Earth increases? 4. What happens to the density as the depth within the Earth increases? 5. When you put your marshmallow into the candle flame, what type of heat transfer were you modeling?

3. Would someone believe the Asthenosphere is made of Jell-O?

4. It makes sense right? We know the Asthenosphere is a “plastic solid” or a solid that can move and flow….just like Jell-O! So why does it sound so crazy?

5. Alfred Wegener (Vegner) got the same response for his theory. http://education-portal.com/academy/lesson/alfred- wegeners-theory-of-continental-drift.html#lesson https://www.youtube.com/watch?v=MEh4B 1Pv8YE

6. Wegener’s Theory of Continental Drift: What is Continental Drift? It is the idea or Theory …….. that the continents slowly move over Earth’s surface. All continents had once been joined together in a single land mass (PANGAEA) and later began to drift apart.

7. Wegener was not alone in thinking that the continents appeared to fit together like puzzle pieces. He, however, came up with a theory to suggest that the continents were once joined together and drifted apart.

8. Sit very still! Can you feel the North American plate moving? It was a pretty radical idea at Wegener’s time to say the continents were moving. Most scientists were skeptical. However, Wegener had evidence…..

9. Wegener’s 3 main pieces of evidence: 1.Landforms- Shapes of the Continents – They appeared to ‘fit’ South America and Africa. Coal Fields - In North America and Europe match up when pieced together (also ‘fit’ as well) Mountains and Rock Layers – In North America and Europe match up when the continents are pieced together (similar rocks)

10. 2. Fossil Evidence - Fossils of the same animals were found on many different continents, now separated by oceans: Glossopteris = plant Cynognathus = land reptile Lystrosaurus = land reptile Mesosaurus = freshwater reptile These organisms had no way to travel across such oceans that exists today! Wegener’s 3 main pieces of evidence:

12. Also, fossils of the Glossopteris (a fern) have been found in rocks of Africa, South America, Australia, India, and Antarctica! Finding these fossils on such widely separated landmasses, convinced Wegener that the continents had once been united.

14. 3. Climate Evidence – Tropical Plants - Found in areas that are considered Arctic (frozen) today. Glaciers - Evidence of glaciers found in areas that have temperatures far too mild to have glaciers. Evidence shows that climate must have been much different in the past Wegener’s 3 main pieces of evidence:

15. So why didn’t Wegener’s fellow scientists accept his theory? He was missing one key point to support his theory? Can you guess what evidence the other scientists wanted to hear?

16. HOW They wanted to know ….. HOW continental drift happened? Wegener could not provide an explanation for the force that pushes or pulls the continents. Case closed, not enough evidence!

17. Most scientists believed that the Earth was cooling and shrinking, which created Earth’s mountain ranges. (like the dried up, wrinkled skin of an apple) Wegener said that if this was true, Mountains should be found all over Earth, but they usually occur in bands along the edges of continents.

18. Unfortunately, Wegener died before his theory was ever accepted. He went on a Meteorological expedition to Greenland one winter, and got lost in a bad snow storm.

19. continental drift animation link http://www.phschool.com/webcodes10/index.cfm?wcprefix=cfp&wcsuffix=1015&f useaction=home.gotoWebCode&x=0&y=0

20. https://www.youtube.com/watch?v=JmC-vjQGSNM