Seismic magnitude scales based on a simple model of rupture, and on certain simplifying assumptions; it incorrectly assumes that the proportion of energy radiated as seismic waves is the same for all earthquakes. Much of an earthquake's total energy as measured by is dissipated as friction (resulting in heating of the crust). An earthquake's potential to cause strong ground shaking depends on the comparatively small fraction of energy radiated as seismic waves, and is better measured on the "energy magnitude" scale, M. The proportion of total energy radiated as seismic varies greatly depending on focal mechanism and tectonic environment; and for very similar
Richter magnitude scale distance of the station, formula_23. In practice, readings from all observing stations are averaged after adjustment with station-specific corrections to obtain the formula_2 value. Because of the logarithmic basis of the scale, each whole number increase in magnitude represents a tenfold increase in measured amplitude; in terms of energy, each whole number increase corresponds to an increase of about 31.6 times the amount of energy released, and each increase of 0.2 corresponds to approximately a doubling of the energy released. Events with magnitudes greater than 4.5 are strong enough to be recorded by a seismograph anywhere in the world, so