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Cyber TEAM Academy 2008 Earth Science Dr. Debi Kilb Scripps Institution of Oceanography. What’s the difference between a “Seismograph” and a “Seismogram”?. Seismograph: The instrument (Apparatus to measure and record vibrations) Seismogram: The actual wiggle
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Cyber TEAM Academy 2008 Earth Science Dr. Debi Kilb Scripps Institution of Oceanography
What’s the difference between a “Seismograph” and a “Seismogram”? Seismograph: The instrument (Apparatus to measure and record vibrations) Seismogram: The actual wiggle (Record of an Earth tremor recorded by a seismograph)
Seismic Waves fault ‘snaps’ energy ripples
Seismograph 3 Main Earthquake Waves • P waves(compressional) 6-8 km/s. Particle motion is parallel to direction of propagation; also called primary waves. • S waves(shear) 3-5 km/s. Particle motion is perpendicular to direction of propagation; also called secondary waves. Do not pass through liquids. • Surface waves(surface) < 3-4 km/s. Waves that travel around the Earth at the surface.
Seismograph Types of Seismic Waves
Ground Motions P Waves S Waves Surface Waves