Plate tectonics with vocabulary

VOCABULARY

plate tectonics-

theory that continents are in slow, constant motion.

continents-

huge land masses

Continental Drift-

the theory that the continents were once a single land mass and have broken apart and “floated” to where they are today

Alfred Wegener-

German geologist who first came up with the Continental Drift theory in 1915

Pangaea-

name that Wegener gave to the land mass known as the Supercontinent

Mid-ocean ridge-

the longest mountain chain in the world

Sea-floor spreading-

At the mid-ocean ridge, molten material rises from the mantle, then spreads out, pushing older rock to both sides of the ridge. This process, called sea-floor spreading, forms the new ocean floor.

magma-

molten mixture of rock-forming substances, gases, and water that make up the earth’s mantle

lava-

magma that has reached the surface; also the rock that’s formed when the liquid lava hardens

volcano

a weak spot in the crust where magma has come to the surface

Video http://www.cbsnews.com/video/watch/?id=7389841n&tag=mncol;lst;10

fault-

a break in rock where the rocks slide past each other; a break in the earth’s crust; earthquakes occur along faults

earthquake-

the shaking that results from the movement of rock beneath the earth’s surface

http://video.nationalgeographic.com/video/player/environment/environment-natural-disasters/earthquakes/earthquake-101.html

uplift-

the raising of the earth’s crust; usually results in mountain formation

intrusion-

molten rock that has squeezed into existing rock and hardened

Intrusion of mafic rock into granite

subduction-

process by which the ocean floor sinks back into the mantle

http://oregonstate.edu/media/trcnb-hiq

rift valley-

a deep valley that forms where two plates move apart