Seismograph Or seismometer is an instrument used to detect and record earthquakes Seismogram A record written by a seismograph in response to ground motions produced by an earthquake explosion or other groundmotion sources ID: 559107
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Slide1
Measuring EarthquakesSlide2
Seismograph
Or seismometer, is an instrument used to detect and record earthquakes.Slide3
Seismogram
A record written by a seismograph in response to ground motions produced by an earthquake, explosion, or other ground-motion sources.Slide4
Seismogram
A record written by a seismograph in response to ground motions produced by an earthquake, explosion, or other ground-motion sources.Slide5
Amplitude
The size of the wiggles on an earthquake recording.Slide6
P or Primary Waves
The fastest type of seismic waves, can travel through liquid and solids. This is a body wave.Slide7
S or Secondary Waves
The second fastest type of seismic wave; cannot travel through materials that are liquid. This is a body wave.Slide8
Body Waves Slide9
Surface Waves
Move the ground roll up and down or shake from side to side as the waves travel along the surface. These cause the most destruction. P and S waves can turn into surface waves.Slide10Slide11
Richter ScaleSlide12
Richter Scale
Video: Slide13
What
scale do
scientist use to measure the magnitude of an earthquake today?
answerSlide14
Moment Magnitude Scale
Video
The
magnitude
is based on the
seismic moment
of the earthquake, which is equal to the rigidity of the Earth multiplied by the average amount of slip on the
fault
and the size of the area that slipped.Slide15
Vocabulary
Richter Scale & Moment Magnitude Scale (MMS):
A quantitative (objective) measure of strength – how much energy the earthquake releases. MMS is the most accurate with 3.5 and higher quakes.
Magnitude = size
or amount of energy releasedSlide16
How many magnitudes
Can there be for one specific earthquake?Slide17
A different type of scale
For measuring the intensity of an earthquakeSlide18
Modified Mercalli
ScaleSlide19
Mercalli
Intensity Scale:
A qualitative (subjective) measure of earthquake’s effect on area – a measure of intensity. Slide20
Magnitude vs. Intensity