GWBN+2.4

toc

Outline
T= Monitoring Faults

1. Devices that Monitor Faults

1. Monitoring Risk in the United States
 * geologists invented instruments to observe faults that
 * measure stress/ deformation in crust
 * creep meter
 * measures horizontal movement of the ground
 * laser-ranging device
 * uses laser beam to detect tiny fault movement
 * tiltmeter
 * measures tilting of ground
 * Satellite Monitor
 * uses satellite with radar to make images of faults
 * Satellite Monitor
 * uses satellite with radar to make images of faults


 * geologists can't predict when/ where earthquake will strike
 * usually stress along fault increases until earthquake occurs
 * sometimes earthquake doesn't occur
 * earthquake may relieve stress along a another part of a fault
 * geologists know
 * earthquakes are likely wherever plate movement stores energy in the rock along faults
 * geologist can determine earthquake risk
 * where faults are active
 * where past earthquakes have occurred
 * In the United States
 * risk is highest along Pacific coast


 * California, Washington, Alaska