The intensity of the earthquakes is valued according to the Richter scale (Charles Francis Richter 26/4/1900 - 30/9/1985) or the modified Mercalli scale (Giuseppe Mercalli 21/5/1850 - 19/3/1914). The first scale furnishes an evaluation (magnitude) of the quantity of freed energy, while the seconds scale assigns a degree to the effects on the environment.
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