Upgrade to remove ads
Only $2.99/month

Chapter 7 - Earthquakes & Earth's Interior

Terms in this set (32)

aftershock
a tremor (or one of a series of tremors) occurring after the main shock of an earthquake
asthenosphere
A subdivision of the mantle situated below the lithosphere. This zone of weak material exists below a depth of about 100 kilometers and in some regions extends as deep as 700 kilometers. The rock within this zone is easily deformed.
body waves
Seismic waves that travel through the Earth's interior
core
The central part of the earth below the mantle
crust
The thin and solid outermost layer of the Earth above the mantle
earthquake
A shaking or sliding of the ground. It is caused by the sudden movement of masses of rock along a fault or by changes in the size and shape of masses of rock far beneath the earth's surface.
elastic rebound
the sudden return of elastically deformed rock to its undeformed shape
epicenter
Point on Earth's surface directly above an earthquake's focus
fault
a fracture in the earth's crust resulting from the displacement of one side with respect to the other
fault creep
displacement along a fault that is so slow and gradual that little seismic activity occurs
focus
Point at the depth where the rocks ruptured to produce earthquakes; place where quake waves originate
foreshock
small earthquakes that often proceed a major earthquake for days or even years
inner core
A dense sphere of solid iron and nickel at the center of Earth
intensity
The rate at which a wave's energy flows through a given area for earthquakes this is measured on the Modified Mercalli scale
liquifaction
The process by which an earthquake's violent movement suddenly turns loose soil into liquid mud.
lithosphere
Earth's rigid layer made up of the crust and uppermost part of the mantle.
magnitude
Measure of the energy released during an earthquake
mantle
Earth's thickest layer made of hot rock and is less dense than the core, less hot, and has less pressure on it. It also has plasticity
mesosphere
The strong, lower part of the mantle between the asthenosphere and the outer core
Modified Mercalli scale
a 12 point scale developed to evaluate earthquake intensity based on the amount of damage to various structures
Mohorovicic discontinuity
the zone between the crust and mantle that marks a boundary between them, discovered because it changes the speed of seismic waves
Moment Magnitude
a more precise measure of earthquake magnitude than the Richter scale, which is derived from the amount of displacement that occurs along a fault zone and estimates the energy released by an earthquake
outer core
A layer of molten iron and nickel that surrounds the inner core of Earth
primary (P) waves
compression waves that cause material to move back and forth along the direction the wave is moving - fastest of the seismic waves
Richter scale
A scale that rates an earthquake's magnitude based on the size of its seismic waves.
secondary (S) waves
transverse waves where the material moves perpendicular to the direction the wave is moving, slower than P waves and only travel in solids
tsunami (aka seismic sea wave)
waves triggers by vertical (upward) displacement on sea floor during earthquakes
seismogram
the record of an earthquake's seismic waves produced by a seismograph
seismograph
A device that records ground movements caused by seismic waves as they move through Earth
seismology
Study of earthquakes
shadow zone
An area on Earth's surface where no direct seismic waves from a particular earthquake can be detected.
surface waves
seismic waves that travel along the Earth's surface
THIS SET IS OFTEN IN FOLDERS WITH...