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Download divergent boundary. Results in volcanos and seafloor spreading
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Plate Tectonics and Continental Drift Continental Drift A theory from Alfred Wegener States that continents can drift apart from one another and have done so in the past Continental Drift This helps to support Pangea Pangea was a landmass of all continents together Pangea means “all earth” Continental Drift Evidence of Continental Drift Continents seem to fit together Fossils of same plants and animals are found on both sides of the Atlantic Ocean Seafloor Spreading Many years later the thought of seafloor spreading was introduced. Seafloor spreading is the process where new oceanic lithosphere is created as materials are pulled away. As plates move apart, the seafloor spreads apart and magma rises to fill in the gap. Seafloor Spreading Mid-ocean ridges occur at areas of seafloor spreading Mid-ocean ridges are underwater mountain chains The Mid-Atlantic Ridge is the largest mountain chain in the world. Plate Tectonics Plate tectonics is the theory that Earth’s lithosphere is divided into plates that move around on top of the asthenosphere. What makes them move??? 3 Possible forces: Ridge Push Convection Slab Pull Plate Boundaries Plates can move 3 different ways. Collide, separate, or slide past one another Plate Boundaries When two plates meet and they push into one another it is called a convergent boundary. Results in mountains and volcanos Plate Boundary Areas where oceanic plates sink down into the asthenosphere is called a subduction zone. Plate Boundary When two plates move away from one another we call it a divergent boundary. Results in volcanos and seafloor spreading Plate Boundary When two plates slide past one another the boundary is called a transform boundary. Results in a lot of earthquakes! Movement of Plates Plates move so slow you can’t feel or see them. Centimeters per year! Motion is monitored through GPS systems. EXIT SLIP Describe continental drift theory. What are the 2 main pieces of evidence for continental drift? Name the 3 types of plate boundaries. Describe the movement at each plate boundary and what results from each .
