25 terms

chapter 7 Plate Tectonics


Terms in this set (...)

The thin and solid outermost layer of the earth above the mantle.
Layer of rock between earth's crust and core.
Central part of the earth below mantle.
Solid outer layer of earth that consists of crust and rigid upper part of mantle.
Soft layer of mantle on which tectonic plates move.
Strong, lower part of mantle between asthenosphere and the outer core.
Tectonic Plates
Blocks of lithosphere that consists of crust and rigid outermost part of the mantle.
Seismic Waves
A wave of energy that travels through the earth and away from an earthquake in all directions.
Continental Drift
The hypothesis that states that the continents once formed a single landmass, broke up, and traveled to their present locations.
Sea-Floor Spreading
The process by which new oceanic lithosphere forms as magma rises towards the surface and solidifies.
Plate Tectonics
The theory that explains how large pieces of the earth's outermost layer move and change shape.
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 plates that are sliding past each other horizontally.
Stress that occurs when forces act to squeeze an object.
Stress occurs when forces act to stretch an object.
Bending of rock layers due to stress.
Break in rock body when one block slides relative to another.
A ___________ fault usually occurs when tectonic forces pull rocks apart because of tension.
A ___________ fault forms when rocks are pushed together by compression.
A __________ fault is the third major type and forms when opposing forces cause rocks to break or move horizontally.
Rising of regions of earth's crust to higher elevations.
Sinking of regions of earth's crust to lower elevations.
Rift Valley
A long, narrow valley that forms as tectonic plates separate. (pg. 385)
Convection Currents
The Sun is the initial energy source of the wind and currents. Because the sun heats the earth more in some places than in others, ___________ are formed.