Seismometer
An instrument that records ground movement most often caused by earthquakes, volcanic eruptions and quarry or mine blasts. Short period seismometers detect seismic events that occur within a few hundred kilometers, whereas broadband seismometers detect local earthquakes as well as those occurring around the world. Accelerometers measure strong shaking from local earthquakes. Seismometers deployed in wells detect very small magnitude microseismic events.