plate tectonics Flashcards
Lithosphere
the solid, outer layer of the Earth that consists of the crust and the rigid upper part of the mantle
Asthenosphere
the soft layer of the mantle on which the tectonic plates move
Mesosphere
the strong, lower part of the mantle between the asthenosphere and the outer core
Seismic wave
A wave of energy that travels through the Earth and away from an earthquake in all directions
Density
the ratio of the mass of a substance to the volume of the substance
Continental Drift
The hypothesis that states that the continents once formed a single landmass, broke up and drifted to their present locations
Convergent Boundary
the boundary formed by the collision of two lithospheric plates
Divergent Boundary
The boundary between two tectonic plates that are moving away from each other
Transform Boundary
The boundary between tectonic that are sliding past each other horizontally
Sea-floor Spreading
The process by which new oceanic lithosphere forms as magma rises toward the surface and solidifies.
Inner core
the solid, dense center of our planet that extends from the bottom of the outer core to the center of the earth
Outer core
the liquid layer of the earth’s core that lies beneath the mantle and surrounds the inner core
Oceanic crust
the outermost layer of Earth’s lithosphere that is found under the oceans and formed at spreading centers on oceanic ridges
Continental crust
the outermost layer of Earth’s lithosphere that makes up the planet’s continents and continental shelves and is formed near subduction zones at plate boundaries between continental and oceanic tectonic plates
Alfred Wegener
German meteorologist and geophysicist who formulated the first complete statement of the continental drift hypothesis
