Radience

Earthquakes

Science

aftershock

a smaller earthquake that follows a bigger one
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earthquake

a sudden shaking of rock in the Earth's crust
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epicenter

the point directly above the focus of an earthquake, on Earth’s surface
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fault

a break in Earth's crust along which rocks move
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focus

the underground point where an earthquake starts
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liquefaction

the shaking during an earthquake which makes wet soil act like a liquid
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magnitude

the strength of an earthquake
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mercalli scale

a measure of the intensity of, and damage caused by an earthquake
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moment magnitude scale

a scale of the energy released by an earthquake
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normal fault

a break in rock caused by tension forces, which causes rocks to slide downward
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primary wave

a seismic wave that vibrates rock particles in the direction that it travels
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reverse fault

a fault caused by compression, which pushes rock upwards
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richter scale

a measurement of earthquake magnitude, based on seismic wave size
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secondary wave

a seismic wave that moves the ground up and down
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seismic gap

an area of few recent earthquakes, but with a history of strong quakes
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seismic wave

an energy wave caused by an earthquake
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seismogram

a record of seismic waves produced by a seismograph
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seismograph

an instrument that records seismic waves
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stress

the force of an object pressing, pushing, or pulling on another object
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strike slip fault

a break in rock where the two blocks move sideways, with little vertical movement
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surface wave

a seismic wave that moves on a surface, it causes both up-and-down and side-to-side movement
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tsunami

a huge wave caused by an underwater earthquake
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