Chapter 08 Vocab Flashcards
Aftershock
The series of smaller earthquakes that follow a major earthquake.
Body Wave
Seismic waves that pass through the interior of the Earth.
Compressional Wave
Waves in which particles of material move back and forth parallel to the direction in which the wave itself moves.
Displacement
The amount of movement or slip across a fault plane.
Earthquake
A vibration caused by the sudden breaking or frictional sliding of rock in the Earth.
Earthquake Early Warning
A communications network that provides an alert within microseconds after the first earthquakes waves arrive at a seismograph near the epicenter, but before damaging vibrations reach population centers.
Earthquake Engineering
The design of buildings that can withstand shaking.
Epicenter
The point on the surface of the Earth directly above the focus of an earthquake.
Fault
A fracture on which one body of rock slides past another.
Fault Scarp
A small step on the ground surface where one side of a fault has moved vertically with respect to the other.
Fault Trace
The intersection between a fault and the ground surface.
Foreshock
The series of smaller earthquakes that precede a major earthquake.
Friction
Resistance to sliding on a surface.
Intensity
A measure of the relative size of an earthquake (the severity of ground shaking) at a location, as determined by examining the amount of damage caused.
Intraplate Earthquake
Earthquakes that occur away from plate boundaries.
Modified Mercalli Scale
An earthquake characterization scale based on the amount of damage that the earthquake causes.
Moment Magnitude Scale
A scale that defines earthquake size on the basis of calculations involving the amount of slip, length of rupture, depth of rupture, and rock strength.
Recurrence Interval
The average time between successive geologic events.
Richter Scale
A scale that defines earthquakes on the basis of the amplitude of the largest ground motion recorded on a seismogram.
Seismic Belt
The relatively narrow strips of crust on Earth under which most earthquakes occur.
Seismicity
Earthquake activity.
Earthquake activity.
The strengthening of an already existing structure (building, bridge, etc.) so that it can withstand earthquake vibrations.
Seismic Wave
Waves of energy emitted at the focus of an earthquake.
Seismogram
The record of an earthquake produced by a seismograph.
Seismometer
An instrument that can record the ground motion from an earthquake.
Shear wave
Seismic waves in which particles of material move back and forth perpendicular to the direction in which the wave itself moves.
Stick-slip behavior
Stop-start movement along a fault plane caused by friction, which prevents movement until stress builds up sufficiently.
Stress
The push, pull, or shear that a material feels when subjected to a force; formally, the force applied per unit area over which the force acts.
Surface Wave
Seismic waves that travel along the Earth’s surface.
Travel-Time Curve
A graph that plots the time since an earthquake began on the vertical axis, and the distance to the epicenter on the horizontal axis.
Tsunami
A large wave along the sea surface triggered by an earthquake or large submarine slump.
Wadati- Benioff zone
A sloping band of seismicity defined by intermediate- and deep-focus earthquakes that occur in the downgoing slab of a convergent plate boundary.
