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Earth science 9th grade
sections of Earth's litosphere that is composed of crust and upper mantle (continental and oceanic plates)
theory that crust and upper mantle move on plastic like layer of the mantle.
ocean crust, continental crust, rigid upper mantle (about 100 km thick)
plastic-like layer beneath the lithosphere
liquid, mostly iron
solid, dense, mostly iron and some nickel
hypothesis that continents moved slowly to their current locations (Alfred Wegener, 1912)
single large land mass made up of all continents connected that broke apart 200 million years ago
theory that magma moving upward spreads seafloor apart at mid ocean
cycle of heating, rising, cooling, sinking that makes plates move
area where one plate sinks below another; most dense plate sinks
area where two plates move towards each other
area where two plates move away from eachother
zone where many volcanos & earthquakes occur
a diverging boundary marked by a rift valley
a crack or break in Earth's crust
block of lithoshere moved thousands of kilometers and attached to the edge of a continent