Tectonic Plates 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 in altitude.
Inner Core
The innermost part of Earth is the core and is about 1500 miles thick.
Outer Core
liquid, an iron-nickel layer of the Earth between the solid inner core and lower mantle.
Seismic Waves
an elastic wave in the earth produced by an earthquake or other means.
Oceanic Crust
the relatively thin part of the earth’s crust that underlies the ocean basins. It is geologically young compared with the continental crust and consists of basaltic rock overlain by sediments.
Continental Crust
the relatively thick part of the earth’s crust that forms the large landmasses. It is generally older and more complex than the oceanic crust.
Density
the degree of compactness of a substance.
Alfred Wegener
Alfred Lothar Wegener was a German climatologist, geologist, geophysicist, meteorologist, and polar researcher.
Continental Drift
the gradual movement of the continents across the earth’s surface through geological time.
Convergent Boundary
When two plates come together
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
the formation of new areas of oceanic crust, which occurs through the upwelling of magma at midocean ridges and its subsequent outward movement on either side.
