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
a layer of Earth’s atmosphere.
Inner Core
a hot, dense ball of (mostly) iron.
Outer Core
mostly composed of liquid iron and nickel.
Seismic Waves
an elastic wave in the earth produced by an earthquake or other means.
Oceanic Crust
the outermost layer of Earth’s lithosphere that is found under the oceans and formed at spreading centres on oceanic ridges, which occur at divergent plate boundaries.
Continental Crust
, the outermost layer of Earth’s lithosphere that makes up the planet’s continents and continental shelves
Density
is the substance’s mass per unit of volume. The symbol most often used for density is ρ although the Latin letter D can also be used.
Alfred Wegener
Alfred Lothar Wegener was a German climatologist, geologist, geophysicist, meteorologist, and polar researcher.
Continental Drift
describes one of the earliest ways geologists thought continents moved over time. This map displays an early “supercontinent
Convergent Boundary
A convergent boundary is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other
Divergent Boundary
divergent boundary or divergent plate boundary is a linear feature that exists between two tectonic plates that are moving away from each other.
Transform Boundary
a broad zone forming as the Pacific Plate slides northwestward past the North American Plate.
Sea-floor Spreading
a geologic process in which tectonic plates—large slabs of Earth’s lithosphere—split apart from each other.
