Studied by 215 PeopleSeismograph
Tags & Description
Seismograph
A device that records ground movements caused by seismic waves as they move through Earth.
Seismologist
A scientist who studies earthquakes.
On a seismograph the suspended mass...
stays at rest while the frame and drum move with the earth.
earthquake magnitude
measure of ground shaking during and earthquake, which depends of distance from epicenter and the geological material.
earthquake intensity
Measure of damage from an earthquake.
S waves (secondary waves)
Seismic waves that shake the ground at right angles compared to the direction of motion. Also, will end when they strike the earth's outer core as it is a liquid.
P waves (Primary waves)
Are body waves that travel through the interior of the Earth. Shake the ground in the same direction as the wave is travelling. Can travel through solids and liquids. The fastest seismic wave type.
Modified Mercalli Scale
Scale that rates earthquake intensity
Richter scale
Scale that measures energy released by a quake
stress
Forces per unit area acting on a material or layers of rock.
fault
Fracture in rock along which movement occurs
tsunami
Wave generated by vertical motions of the seafloor
seismic gap
Section of an active fault that has not experienced a significant earthquake for a long time
surface wave
Seismic wave that causes the ground to move in two directions
How many seismic stations are necessary to find the epicenter of an earthquake?
At least 3.
The fact that a significant earthquake has not occurred within a seismic gap indicates that an earthquake is more likely to occur in the near future.
True
Movement occurs along fractures in rocks when
stress overcomes the strength of the rocks involved
The stress which causes a material to twist is known as
shear
The stress which causes a material to pull apart is known as
tension
P-waves and S-waves are also known as
body waves
Epicenter
Point on Earth's surface directly above an earthquake's focus. Location of the most intense damage. Location of the highest magnitude of shaking.
Focus
The point of failure where the waves originate.
Seismic Gap
A location where a city is located over a fault but has not experienced an earthquake in a long time.
San Andreas Fault
Strike Slip Fault
Reverse Fault
formed from compression. Found in mountains.
seismic belts (seismic zones)(Ring of Fire)
The relatively narrow strips of crust on Earth under which most earthquakes occur
locations of seismic belts are determined by
plotting earthquake epicenters
Deaths associated with earthquakes in sloping areas can result from
landslides, avalanches
Seismic waves change speed and direction when they encounter different materials.
True
P-waves travel through Earth's mantle.
True
Surface waves will arrive first at any location.
False
As you travel farther from the epicenter of an earthquake...
seismic waves are spread farther apart.
moment magnitude scale
A numerical scale of earthquake magnitude that takes into account the size of the fault rupture
The scale that uses roman numerals.
Mercalli Scale
As the distance from a quake's epicenter increases...
intensity and magnitude decrease.
