Plate Tectonics Write on RIGHT Side

What discoveries support continental drift? In mid 1900s, scientists found under-water mountain ranges called mid-ocean ridges. This discovery led to the Theory of Plate Tectonics

Theory of Plate Tectonics Theory of Plate Tectonics Describes why and how the Earth’s surface changes Theory of Plate Tectonics

Tectonic Plate- large piece of lithosphere that is floating on the asthenosphere The word “Tectonic” is Greek for “builder” Tectonic Plates build and shape our Earth (mountains, earthquakes, volcanos, etc.) Tectonic Plates

Plates move at different speeds and in different directions Oceanic plates are more dense than continental plates Tectonic Plates

Why do tectonic plates move? Mantle Convection– the rock rises and falls due to changes in density. The rock heats and rises, then cools and sinks

Mid-Ocean Ridges Mid-ocean ridges form along cracks in the crust Youngest rock is closest to the ridge, oldest rock is farthest away

Sea Floor Spreading the process where molten rock inside the Earth rises through the cracks in the ridges, cools, and forms new oceanic crust Sea- Floor Spreading

Mid- Ocean Ridges forming and Sea-Floor Spreading https://www.youtube.com/watch?v=ryrXAGY1dmE

Reflection (Left Side) Copy the information and draw the picture of convection taking place in the mantle Reflection (Left Side)