Energy class based on an earthquake's seismic energy, although S. L. Solov'ev seems to have made major contributions. (In contrast to the "Richter" and other magnitude scales developed by Western seismologists, which estimate the magnitude from the amplitude of some portion of the seismic waves generated, an indirect measure of seismic energy.) However, proper estimation of E requires more sophisticated tools than were available at the time, and Bune's method was unworkable. A more practical revision was presented by T. G. Rautian in 1958 and 1960; by 1961 K-class was being used across the USSR. A key change was to estimate E
Richter magnitude scale isolated area. Several scales have historically been described as the "Richter scale", especially the "local magnitude" formula_2 and the surface wave formula_3 scale. In addition, the "body wave magnitude", formula_4, and the "moment magnitude", formula_5, abbreviated MMS, have been widely used for decades. A couple of new techniques to measure magnitude are in the development stage by seismologists. All magnitude scales have been designed to give numerically similar results. This goal has been achieved well for formula_2, formula_3, and formula_5. The formula_4 scale gives somewhat different values than the other scales. The reason for so many different ways to measure