seismographs and seismometers are used in suspected "at risk" areas of tectonic activity (earthquakes and volcanoes)
Seismometers. For information on how seismometers are used, please see the related question.
A seismograph.
seismograph
Seismograph
A seismograph is used to measure ground movement or vibrations on the Richter scale.
The correct spelling (transposed) is seismograph(measures and records seismic activity).
seismograph scale
Seismograph.
a seismograph
it records the magnitude of earthquakes.
a seismograph
Lilly, who is a scientist, used a seismograph to determine the strength of the earthquake that had just hit Haiti.