Seismometer

Instrument that records seismic waves by measuring ground motions

A seismometer is an instrument that responds to ground displacement and shaking caused by quakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The output of such a device—formerly recorded on paper (see picture) or film, now recorded and processed digitally—is a seismogram.

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