earthquake energy

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earthquake energy The amplitude of a seismic signal is proportional to the energy (E) released in an earthquake. There is no consensus on the actual equation. This is based on the Richter magnitude but also depends on the frequency of the wave, distance from the source, etc., and is of the form logE = aM + b. The annual energy dissipation by this means is estimated to be more than 1011 watts, of which 75% is released in shallow earthquakes and 3% in deep.