Earthquakes 101 EQ101

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Earthquakes 101 (EQ101)
USGS Earthquake Hazards Program
Lisa Wald USGS Pasadena
U.S. Department of the Interior U.S. Geological
Survey
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Global Distribution of Earthquakes
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Plate Tectonics
USGS Earthquake Hazards Program
Lisa Wald USGS Pasadena
U.S. Department of the Interior U.S. Geological
Survey
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Plate Boundaries
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Three Types of Faults
Strike-Slip
Reverse
Normal
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Strike-slip Fault Example
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Strike-slip Fault Example
1906 San Francisco Earthquake
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The San Andreas Fault
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Will California eventually fall into the ocean???
No!
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Pacific-North American Plate Boundary
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Normal Fault Example
Dixie Valley-Fairview Peaks, Nevada
earthquake December 16, 1954
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Reverse Fault Example
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What Controls the Level of Shaking?

• Magnitude
• More energy released
• Distance
• Shaking decays with distance
• Local soils
• amplify the shaking

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Is there such a thing as Earthquake Weather???
No!
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Earthquake Effects - Ground Shaking
Northridge, CA 1994
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Earthquake Effects -Ground Shaking
Northridge, CA 1994
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Earthquake Effects - Ground Shaking
Loma Prieta, CA 1989
KGO-TV News ABC-7
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Earthquake Effects - Ground Shaking
Kobe, Japan 1995
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Earthquake Effects - Ground Shaking
Kobe, Japan 1995
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Earthquake Effects - Surface Faulting
Landers, CA 1992
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Earthquake Effects - Liquefaction
Source National Geophysical Data Center
Niigata, Japan 1964
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Earthquake Effects - Landslides
Source National Geophysical Data Center
Turnnagin Heights,Alaska,1964
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Earthquake Effects - Fires
Loma Prieta, CA 1989
KGO-TV News ABC-7
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Earthquake Effects - Tsunamis
1957 Aleutian Tsunami
Photograph Credit Henry Helbush. Source
National Geophysical Data Center
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Earthquake Magnitude
M5
M6
M7
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Earthquake Location
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USGS Earthquake Hazards Program
U.S. Department of the Interior U.S. Geological
Survey
Where to go for more information
http//pasadena.wr.usgs.gov/ http//earthquake.usg
s.gov/
The End