Earthquakes are measured using a seismometer, an instrument that measures the movements of the ground caused by seismic waves. The data collected by the seismometer is used to determine the earthquake's magnitude, which is a measurement of the energy released by the earthquake. The magnitude is expressed on the Richter scale, which ranges from 0 to 10, with each increase of one representing a 10-fold increase in the earthquake's strength. The actual strength, or intensity, of the earthquake at a particular location is measured using the Modified Mercalli Intensity Scale. This scale ranges from I (not felt) to XII (catastrophic damage). The magnitude and intensity of an earthquake can help determine its potential impact on people, buildings, and infrastructure.
