plate tectonics Flashcards
Lithosphere
the solid, outer part of Earth.
Asthenosphere
the upper layer of the earth’s mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur.
Mesosphere
a layer of Earth’s atmosphere.
Inner Core
a hot, dense ball of (mostly) iron.
Outer Core
liquid, iron-nickel layer of the Earth between the solid inner core and lower mantle.
Seismic Waves
caused by the sudden movement of materials within the Earth, such as slip along a fault during an earthquake.
Oceanic Crust
the outermost layer of earth under the oceans.
Continental Crust
the layer of granitic, sedimentary, and metamorphic rocks, which form the continents and the areas of shallow seabed close to their shores
Density
the substance’s mass per unit of volume.
Alfred Wegener
German meteorologist and geophysicist
Continental Drift
the movement of the Earth’s continents relative to each other, thereby appearing to drift together across the oceanic bed.
Convergent Boundary
This occurs when plates move towards each other and collide.
Divergent Boundary
occurs when two tectonic plates move away from each other.
Transform Boundary
places where plates slide sideways past each other.
Sea-floor Spreading
a geologic process in which tectonic plates—large slabs of Earth’s lithosphere—split apart from each other.
