Monitoring Earthquakes

Seismograph: a device used to record movement from seismic waves

Seismogram: the record of seismic waves Provide us with the arrival times for P, S, and L waves The height of the lines indicated severity of the seismic wave

Fault Monitoring

Scientist monitor faults for vertical and horizontal movement Scientist use a variety of detectors to measure changes around a fault Scientist can NOT predict earthquakes, but they can map information

that can determine risk areas

1. Tiltmeters: Measure the changes in liquid levels inside a container Measures vertical movement

2. Creep meters: Measures the movement of a wire that is anchored on both side of a

fault Measures horizontal movement

3.Laser-Ranging Device Measure the movement of a laser beam that is reflected across a fault Measures horizontal movement

4. GPS Satellites Measures changes in elevation, tilt, and horizontal motion Measures horizontal and vertical motion