1935 – USA
‘A scale ranging from 0 to 9 to measure the magnitude of earthquakes’
CHARLES RICHTER
The Richter scale is a numerical scale that gives the magnitude of an earthquake by calculating the energy of shock waves at a standard distance. The scale is logarithmic, so each additional point represents a tenfold increase in severity. Thus a magnitude 7.0 earthquake is 10 times as powerful as one of magnitude 6.0 and 100 times as powerful as one of magnitude 5.0.
In terms of energy, one unit represents an increase in the energy of roughly 3 times. A magnitude 7.0 earthquake unleashes about 1000 times the energy released by a magnitude 5.0 earthquake.
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