Geo 284, Earthquakes

These pages provide some basics for Earthquake Seismology

Overview of Earthquakes

• What?
  • Slip on a fault
  • ...generates seismic waves
    Click for fault slip & waves
• Where?
  • Mostly plate boundaries
  • Mostly subduction zones
    Click for global seismicity
• How Big?
  • Intensity
    Click for Intensity Map of Lansing EQ
  • Magnitude
    Click for the Richter Scale
  • Fault size & slip
• How Many?
  • A few big ones
  • ... lots of little ones
    Click for number of Earthquakes vs. Magnitude
    Connection from Magnitude to Fault Area
    ...allows a physical interpretation of the Gutenberg-Richter relationship
    The Gutenberg-Richter relation in terms of fault area of earthquakes (words)
    The Gutenberg-Richter relation in terms of fault area of earthquakes (picture)
    
  • Thus, the numbers of earthquakes versus their fault area is a power law distribution
    Review of exponents & logarithms
    Power law distribution
    two other examples of power law distributions
    
• When?

• Back to Geo 284 main page