‘Magnitude’ of Quakes No Longer Necessarily Means ‘Richter Scale’

The Times no longer reports earthquake magnitudes as readings on the Richter scale. Magnitude readings now issued by seismologists more often represent composites drawn from a number of earthquake measurements, of which the Richter scale is one.

The Richter scale, developed by the late Caltech seismologist Charles Richter in 1935, was designed to measure the size of an earthquake at its epicenter. Since then, scientists have developed many other ways of measuring the power of an earthquake, and magnitude ratings now may reflect a combination of all of these scales.