Richter Scale Magnitude to Energy

The Richter magnitude scale assigns a magnitude number to quantify the size of an earthquake. The Richter scale is a base 10 logarithmic scale, which defines magnitude as the logarithm of the ratio of the amplitude of the seismic waves to an arbitrary, minor amplitude, as recorded on a standardized seismograph at a standard distance. The energy release is generally proportional to the shaking amplitude raised to the 3/2 power.