How Does a Seismometer Work?

A seismograph is a device for measuring the movement of the earth, and consists of a ground-motion detection sensor, called a seismometer, coupled with a recording system. This fact sheet provides an overview of the basic components of a seismometer and physical science principles behind its operation.


Keypoints:

  • A seismograph is a device for measuring the movement of the earth, and consists of a ground- motion detection sensor, called a seismometer, coupled with a recording system.
  • Seismographs operate on the principle of inertia
  • Seismometers used in earthquake studies are highly sensitive to ground movements, so that movements as small as 1/10,000,000 centimeters (distances almost as small as atomic spacing) can be detected at very quiet sites.
  • Modern research seismometers are electronic, and detect and record motions in all directions. 

 

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Level: Novice

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