Studio macrosismico del terremoto di Mistretta del 5 giugno 1977 e considerazioni sulla sismicità dei Monti Peloritani-Nebrodi-Madonie.

This paper reports a macroseismic study of the Mistretta June 1977 earthquake. Besides the isoseismals map, drawn according to the M.S.K. scale, the map of the epicentres and their density has been prepared taking into account the earthquakes from 1783 to 1977, that occurred in the investigated area. As a result a good agreement has been noted between the epicentral density distribution and the most important tectonic features of the zone. For a more complete correlation with the seismicity of the studied area, a comparison with the isoseismal maps of past earthquakes has been made. Moreover by using the method of SHEBALIN (1972), it has been tried to have information on source parameters of this earthquake. Finally a statistical approach to the seismicity of the area has been carried out, by using the Gutenberg-Richter relationship, the strain release curve and computing the return periods.