How earthquakes are measured
The Richter Scale
Earthquake magnitude is measured on a scale created by Charles F. Richter in 1934. The Richter scale is a numerical calculation with the number rising with the severity of the tremors. It has no upper limit and is based on a logarithmic scale (base 10,) which means intensity - and damage - increases tenfold with each whole number. A seismograph, pictured here, measures the intensity of earthquakes.
PICTURES: Deadliest Earthquakes
Credit: AP
