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TRANSCRIPT
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Chapter 4
Seismology Measuring the interior
School of Earth and Environmental SciencesSchool of Earth and Environmental SciencesJunkee Rhie
4.1 Waves through the EarthThe importance of Seismology
Seismology is the most powerful technique for sampling and constraining the physical structure of the Earth’s interior
• By studying the propagation of elastic waves through the Earth we can learn about the physical properties of the Earth’s interior
• Seismic waves sample narrow swaths of the Earth’s interior
• We can produce a CAT-scan of the Earth
• Seismology was central to the discovery of plate tectonics
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4.1 Waves through the EarthSeismological techniques
4.1 Waves through the EarthBody waves and surface waves
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4.1 Waves through the EarthBody waves
4.1 Waves through the EarthEnergy sources and receivers
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4.1 Waves through the EarthP-waves
4.1 Waves through the EarthS-waves
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4.1 Waves through the EarthWaves
4.1 Waves through the EarthSeismic waveform
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4.1 Waves through the EarthSeismometer
4.1 Waves through the EarthVelocity and density – Birch’s Law
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4.1 Waves through the EarthNafe-Drake curve
4.1 Waves through the EarthVp vs. Depth
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4.1 Waves through the EarthSurface waves
4.1 Waves through the EarthSurface waves - amplitude
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4.1 Waves through the EarthSurface wave propagation
ShakeMovie by Caltech (www.shakemovie.caltech.edu)
4.1 Waves through the EarthLove and Rayleigh waves
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4.1 Waves through the EarthLove and Rayleigh waves
4.1 Waves through the EarthSeismic waveforms
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4.1 Waves through the EarthSeismic waveforms
4.1 Waves through the EarthSurface waves – velocity sensitivity
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4.1 Waves through the EarthGroup and phase velocity
4.1 Waves through the EarthDispersion
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4.1 Waves through the EarthDispersion curves and seismic velocity
4.1 Waves through the EarthFree oscillations
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4.1 Waves through the EarthFree oscillations
4.1 Waves through the EarthFree oscillations – excited by 2004 Sumatra (Mw = 9.0) earthquake
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4.2 Earthquake seismologyLocating earthquakes
4.2 Earthquake seismologyLocating earthquakes
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4.2 Earthquake seismologyLocating earthquakes
4.2 Earthquake seismologyLocating earthquakes
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4.2 Earthquake seismologyLocating earthquakes
4.2 Earthquake seismologyEarthquake depth
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4.2 Earthquake seismologyEarthquake distribution
4.2 Earthquake seismologyEarthquake depth distribution
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4.2 Earthquake seismologyEarthquake size
4.2 Earthquake seismologyIntensity : ShakeMap
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4.2 Earthquake seismologyIntensity and magnitude
4.2 Earthquake seismologyRichter magnitude –Wood-Anderson seismometer
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4.2 Earthquake seismologyRichter magnitude –Wood-Anderson seismometer
4.2 Earthquake seismologyRichter magnitude –Wood-Anderson seismometer
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4.2 Earthquake seismologyRichter magnitude – Today
4.2 Earthquake seismologyBody wave magnitude (mb)
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4.2 Earthquake seismologySurface wave magnitude (Ms)
4.2 Earthquake seismologyMagnitude as a discriminator
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4.2 Earthquake seismologyMagnitude-frequency relation
4.2 Earthquake seismologyMagnitude and frequency
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4.2 Earthquake seismologyEarthquake energy
4.2 Earthquake seismologySeismic moment – Best measure of earthquake size
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4.2 Earthquake seismologyFocal mechanism
4.2 Earthquake seismologyFirst motion
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4.2 Earthquake seismologyIndicative fault type
4.2 Earthquake seismologyPlate boundaries
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4.2 Earthquake seismologyNomenclature
4.2 Earthquake seismologyWaves through the Earth
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4.2 Earthquake seismologyArrival times
4.2 Earthquake seismologyShort period arrival times
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4.2 Earthquake seismologyArrival times
4.2 Earthquake seismology1D velocity model for the Earth
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4.2 Earthquake seismologyVelocity and Mineralogy
4.2 Earthquake seismology3D velocity variations
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4.2 Earthquake seismologyMantle convection
4.2 Earthquake seismologyTomography
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4.2 Earthquake seismologyBorehole tomography
4.2 Earthquake seismologySubduction
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4.2 Earthquake seismologySubduction
4.2 Earthquake seismologySubduction
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4.2 Earthquake seismologyMid-ocean ridge
4.2 Earthquake seismologyMid-ocean ridge
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4.2 Earthquake seismologyHotspots and mantle plumes
4.2 Earthquake seismologyIceland
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4.2 Earthquake seismologyIceland and Azores Canary Cape Verde
4.2 Earthquake seismologyHawaii plume
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4.2 Earthquake seismologyAfrican cratons