Presentation on theme: "Sea-Floor Spreading 10/3/14 7-2b pgs. 175-176 IN: List 3 pieces of evidence Wegener found to help support his theory of continental drift. Glue in the."— Presentation transcript:
Sea-Floor Spreading 10/3/14 7-2b pgs IN: List 3 pieces of evidence Wegener found to help support his theory of continental drift. Glue in the diagram Put your Pangaea Puzzle on the books
What is Wegener’s Evidence? Fossils of the same plant and animal species are found on both sides of the Atlantic Ocean.
What is Wegener’s Evidence? Similar types of rock and evidence of the same ancient climatic conditions were found on several continents.
What is Wegener’s Evidence? Split mountain ranges.
More Evidence Meteorite strike.
Do you believe his theory? What is Wegener still missing?
Wegener could not explain What force is moving the continents? In 1930, Wegener died on a trip to Greenland.
In the 1950s, the ocean floor was surveyed in detail, that their full extent became known.
Mid-Ocean Ridges Underwater mountain chains that run through Earth’s ocean basins.
Sea-floor Spreading The process by which new oceanic lithosphere is created as older materials are pulled away.
Sea-floor Spreading Remember oceanic crust is more dense than continent crust so it sinks down.
Young rocks are near the Mid-Ocean Ridge Old rocks are closer to the coastlines.
Fig Evolution of a Divergent Plate Boundary
Magnetic Reversal When Earth’s magnetic poles change place.
OUT: Explain why Wegener’s Theory of Continental Drift was not correct.