Chapter 5, Section 4Monitoring Faults

Friday, February 19, 2010

Pages 168 -- 171

Objectives

Discover how geologists monitor faults.Understand how geologists determine

earthquake risk.

Monitoring Faults

Geologists place instruments that measure stress and deformation in the crust. This is a means that geologists use to try to

predict when and where an earthquake will occur.

Highest risks areas are determined by locating faults that are active and where past earthquakes have occurred.

Fault Monitoring Devices

Four instruments are used to monitor faults. Creep meters Laser-ranging devices Tiltmeters Satellites

Creep Meters

Creep meters use a wire stretched across a fault to measure sideways movement of the ground.QuickTime™ and a

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Laser-Ranging Devices

Laser-ranging devices use a laser beam that bounces off a reflector that detects even the slightest fault movements.

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Tiltmeters

Tiltmeters measures how much the ground has tipped along a fault.

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Satellites

Satellites use radio waves to bounce off the ground to measure changes in elevation.QuickTime™ and a

TIFF (Uncompressed) decompressorare needed to see this picture.

Homework

Workbook 5.4 -- Monday, 2/22Vocabulary Quiz 5.4 -- Wednesday, 2/24