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Plate Tectonics. Plate Tectonics is a theory that describes the formation, movements, and interactions of Earth’s plates. Alfred Wegener, a German meteorologist, proposed a hypothesis called Continental Drift in 1912.
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Plate Tectonics is a theory that describes the formation, movements, and interactions of Earth’s plates.
Alfred Wegener, a German meteorologist, proposed a hypothesis called Continental Drift in 1912.
Continental Drift supposed that the continents have moved, or drifted, from one location to another over long periods of time.
Continental Drift supposed that the continents have moved, or drifted, from one location to another over long periods of time.
Similar rock formations were found in South America and Africa.
Climate Change: Areas once covered in glaciers are now in warmer climate zones.
The Theory of Plate Tectonics suggests that the continents are part of the lithospheric plates.Evidence for this:
Volcano, Earthquake, and Mountain Belts are located along plate boundaries.
The rock record shows that the magnetic field of the Earth has reversed many times.
Divergent Boundary Rift Valleys and Mid-Ocean Ridges
Convergent Boundary Deep Sea Trenches, Subduction Zones, and Mountain Ranges
Convergent Subduction Less Dense (Continental or Oceanic Crust) More Dense (Oceanic Crust)
Convergent Collision Equal Density Continental Crust
Transform (Strike-Slip) Boundary San Andreas FaultDivision between North American and Pacific Plates
North American Plate Pacific Plate Pacific Plate North American Plate San Andreas FaultDivision between North American and Pacific Plates
Mantle Convection: The mantle moves the plates along as it convects (heats from below). Mantle Convection Animation #2
Ridge Push: The accumulating magma at a mid-ocean ridge “pushes” material away.
Slab Pull: When a plate subducts, it pulls the rest of the plate with it.