29 terms

Dynamic planet vocab

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Asthenosphere
Soft and plastic layer in Earths upper mantle, just below the lithosphere, where convection currents occur
Outer core
Liquid layer of the Earth 2nd layer from the center, made of iron and nickel
Inner core
Solid, inner layer of the Earth made of iron and nickel
Lithosphere
Outer layer of the earth are up of crust and rigid mantle
Moho
Boundary between crust and rigid mantle
Continental crust
Crust on land; thicker, made out of granite, less dense than oceanic crust
Oceanic crust
Crust under the ocean; thinner, more dense, made of basalt
Theory of continental drift
Theory of millions of years ago all the continents were joined together as a single landmass known as the supercontinent Pangea, which due to the motion of tectonic plates broke apart and drifted, forming the modern continents
Plate tectonic theory
Earths crust is made up of a number of tectonic plates. The theory explains the motion of these plates
Tectonic plate aka Lithosphereic plate
Continental plates the earth is divided Into
Convection currents
Convection involves the cyclical movement of hot and cold materials due to density changes

****occurs in the ASTHENOSPHERE
Divergent plate boundary
Where two tectonic plates move apart
Convergent plate boundary
Where two tectonic plates are moving toward each other
Transform plate boundary
Where two plates slide horizontally past one another in opposite directions
subduction
the sinking of an oceanic plate beneath a plate of lesser density at a convergent boundary
original horizontality
rocks form as horizontal layers; so if they aren't horizontal, there has been crustal movement
uplift
the process of crust moving upwards in altitude due to rising of magma beneath the surface (could form mountains or folds or faults)
folded rocks
crustal movement causes horizontal rock layers to bend
fault
a crack in a body of rock along which rocks on opposite sides slide past each other
Earthquake
sudden movement of rock within Earth's crust caused by accumulated stress along a fault
focus
during an earthquake, the location where the actual rock breaking occurs
epicenter
during an earthquake
Seismic wave
energy waves given off by an earthquake
seismograph
instrument used to measure waves from an earthquake
s-wave
transverse seismic wave generated by earthquakes; also called shear waves or secondary waves (slower then P-waves)
p-wave
compressional seismic waves generated by earthquakes (fastest type of seismic wave)
tsunami
a giant ocean wave caused by the sudden displacement of large amounts of sea water by earthquakes, other seismic activity, or massive landslides
hot spot
hot, stationary point below the lithosphere where melting of the mantle an crust generates volcanism at earths surface
Seismic wave
energy waves given off by an earthquake