Presentation is loading. Please wait.

Presentation is loading. Please wait.

Restless Continents  continental drift: the hypothesis by Alfred Wegener that states that the continents once formed a single landmass, broke up, and.

Similar presentations


Presentation on theme: "Restless Continents  continental drift: the hypothesis by Alfred Wegener that states that the continents once formed a single landmass, broke up, and."— Presentation transcript:

1 Restless Continents  continental drift: the hypothesis by Alfred Wegener that states that the continents once formed a single landmass, broke up, and drifted to their present locations. - many fossils & rocks are found only on certain parts of certain continents.

2 Restless Continents - the continents slowly drifted away from Pangaea, which was the super-continent that existed 245 million years ago. (same time as dinosaurs)

3 Restless Continents  sea-floor spreading: the process by which new oceanic lithosphere forms as magma rises toward the surface and solidifies.

4 Restless Continents - the best evidence of sea-floor spreading comes from magnetic reversals recorded in the ocean floor. - iron in the newly formed rock at the mid-ocean ridges has a magnetic field that is slowly spreading across the sea floor & reversing the polarity. - this occurs once every 200,000 years

5 Restless Continents


Download ppt "Restless Continents  continental drift: the hypothesis by Alfred Wegener that states that the continents once formed a single landmass, broke up, and."

Similar presentations


Ads by Google