Plate Tectonics Flashcards
Lithosphere
the rigid outer part of the earth, consisting of the crust and upper mantle.
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
the region of the earth’s atmosphere above the stratosphere and below the thermosphere, between about 30 and 50 miles (50 and 80 km) in altitude.
Inner Core
The inner core is the fourth layer inside the Earth. It is a solid metallic ball made mainly of iron.
Outer Core
Earth’s outer core is a fluid layer about 2,400 km thick and composed of mostly iron
Seismic Waves
Seismic waves are waves that travel through or over Earth.
Oceanic Crust
the outermost layer of Earth’s lithosphere that is found under the oceans.
Continental Crust
continental crust, the outermost layer of Earth’s lithosphere that makes up the planet’s continents
Density
The density, of a substance is its mass per unit volume.
Alfred Wegener
Alfred Lothar Wegener was a German climatologist, geologist, geophysicist, meteorologist, and polar researcher.
Continental Drift
Continental drift was a revolutionary theory explaining that continents shift position on Earth’s surface.
Convergent Boundary
When two plates come together, it is known as a convergent boundary.
Divergent Boundary
A divergent boundary occurs when two tectonic plates move away from each other.
Transform Boundary
Transform boundaries are places where plates slide sideways past each other. At transform boundaries lithosphere is neither created nor destroyed.
Sea-floor Spreading
Seafloor spreading is a geologic process in which tectonic plates—large slabs of Earth’s lithosphere—split apart from each other.
