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Fingerprint of an Earthquake Fingerprint of an Earthquake
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Fingerprint of an Earthquake

Fingerprint of an Earthquake
A seismograph produced this record of a California earthquake measuring 5.5 on the Richter scale. The finger points to a heavy sweep on the seismogram created by the seismograph’s needle, or stylus, which is designed to respond to horizontal or vertical vibrations, but not both. The machine cannot record both kinds of waves because the different orientation of the wave types requires separate balance systems.
UPI/THE BETTMANN ARCHIVE
Appears in these articles:
Earthquake; Seismology
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