continentaldrifttheory-200429120606 (2).pptx

Science

1. CONTINENTAL DRIFT THEORY

2. Describe the World

3. https://vimeo.com/14258924

4. Continents Drifting idea… Abraham Ortelius, a Brabantian cartographer and geographer and known as the creator of the first modern atlas ( Theatrum Orbis Terrarum or Theatre of the World). Ortelius was the first to underline the geometrical similarity between the coasts of America and Europe- Africa and to propose continental drift as an explanation.

5. It refers to the movement of the Earth’s continents relative to each other, appearing to “drift” across the ocean bed. This theory is publish in the book, “Origin of Continents and Oceans” by Alfred Wegener Continental Drift Theory

6. It was fully developed by Alfred Wegener (1880- 1830) , a German meteorologist. According to Wegener, the continents were once joined together in a one large landmass called “ supercontinent ” or “ Pangaea ” Continental Drift Theory

7. The Pangaea break- up led to an increase in seaways and shorelines, which may have been affected the diversification of terrestrial plants and animals by creating several isolated continental regions. During the final drifting of Pangaea, rapid seafloor spreading caused a tremendous released of carbon dioxide gas. Which led to dramatic global warming that culminated about 92 million years ago. Continental Drift Theory

8. Topographic Evidence Fossil Correlation Rock Formation Paleoclimatic Evidence W egene r ’s Evidence

9. Wegener noticed that the continents seemed to fit together. The “good fit” suggested that just like neighboring pieces of a jigsaw puzzle, the continents were once connected in a single supercontinent. He pieced together the map of Africa and South America. Wegener’s Evidence: T opographic Evidence

10. T opographic Evidence

11. Fossils are traces and remains of organism that lived in pre- historic times. Wegener’s Evidence: Fossil Correlation One of Wegener’s example is the remains of Mesosaurus.

12. Fossil Correlation

13. Before Pangea broke apart, similar layers of rocks were formed in Antarctica, Australia, South America, Africa and India. Glossopteris fossils were found in the rocks on each continent. Wegener’s Evidence: Fossil Correlation

14. Rocks and fossils in the continents located in the southern hemisphere exhibit identical pattern known as “ Gondwana Sequence ”. These rocks were of the same age and type. Wegener’s Evidence: Rock Formation

15. US Appalachian Mountains are similar to Greenland and Europe Wegener’s Evidence: Rock Formation

16. Wegener considered as evidence the glacial till deposits in the northern and southern latitudes. It was said that the Earth’s climate has not changed, instead the positions of the continents have changed. Wegener’s Evidence: Paleoclimatic Evidence

17. Wegener’s Evidence: Paleoclimatic Evidence The discovery of fossils from tropical plants in the form of COAL DEPOSITS in Antarctica. Possibly, Antarctica used to be close to the equator where the climate is warmer.

18. Paleoclimatic Evidence

19. Glacial till & striations found in deserts Wegener’s Evidence: Paleoclimatic Evidence

20. Wegener’s Evidence: Paleoclimatic Evidence Franz Josef Glacier in New Zealand

21. So, 🖂hat’s 🖂rong 🖂ith Wegener’s TheoryS Most geologist did not believe Wegener.

22. Wegener’s theory is rejected by some because… Wegener’s theory of continental drift was just too weak for most geologists to accept. Even though he believed the supercontinent that broke up into different continents moved, he did not have a clear explanation to how the continents moved. Some of Wegener’s explanation clashed with ideas that were widely accepted in the science communities. He used similar fossils from different continents to back up his theory of continental drift. However, at that time, many scientists that had observed similarities in fossils in places like South America and Africa believed there were similar fossils in different continents because of a land bridge that were formed by two continents.

23. CONTINENTAL DRIFT THEORY Imagine that you were with Alfred Wegener to defend his Continental Drift Theory. Help him answer the following questions from the skeptic scientists. How do continents drift from each other? What causes them to drift apart?

24. That Alfred Wegener’s original name for his proposed, ancient continent was “Urkontinent”— ur meaning “first or original,” and kontinent meaning “continent” in Wegener’s native language, German. A more popular name for this huge ancient landmass is Pangaea, which means “all lands” in Greek. That despite all these incredible evidences for continental drift, Wegener was not able to see his theory gain acceptance. He died in 1930 at the age of 50 from a probable heart failure while on a scientific expedition in Greenland. It was only in 1950s were new evidences emerged to support his theory and develop a new one.

25. Visit the following websites: https://www.slideshare.net/AbbieMahinay https://www.slideserve.com/devon/chapter- 8- plate- tectonics https://www.youtube.com/watch?v=Wq9kLzm36h0 https://www.youtube.com/watch?v=bQywDr- btz4