Continental Drift Theory TemplatePresentation Transcript
Born on November 1 1880 in Berlin.
Died on November 2, 1930 in Greenland
He was German
He proposed the idea of there being a continental drift in 1915
He studied meteorology, geology, and Astronomy.
Continental Drift Theory
Alfred Wegener’s hypothesis was that all the continents had once been joined together in a single landmass, and have since drifted apart. This one single landmass was named Pangaea.
Continental Drift Theory Evidence
Wenger found 3 evidences. One was the landforms, and how they fitted perfectly together. Plus the Mt. ranges matched up with those on other continents. He also found evidence from fossils. He found fossils of 2 identical prehistoric animals on different continents, that had to be together once. The last evidence was from the climate. He found fossils of tropical plants on cold lands which would have had to be warm sometime. Those are the 3 evidences.
Born on May 24, 1906
Died August 25, 1969
Known for his theories of sea-floor spreading
Sea Floor Spreading
When at the mid-ocean ridge molten material rises from the mantle and erupts. The molten material spreads out pushing older rock to both sides of it.
Sea Floor Spreading Evidence
Hess also used 3 evidences. One was from molten material he found on the bottom of the ocean, he described it as pillows or toothpaste. These shapes could only be made by magma erupting. The second evidence is magnetic stripes. On each side the patterns were equal. The last one is drilling samples. The further away the rock was from the mid-ocean ridge the older the rock was.
Subduction- The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary
Mid-Ocean Ridge- The undersea mountain chain where new ocean floor is produced; a divergent plate boundary.
Sonar- A device that determines the distance of an object under water by recording echoes of sound waves.