The tectonic setting of Mount Vesuvius and the correlation between its eruptions and the earthquakes of the Southern Apennines

Mount Vesuvius is emplaced on a regional NE-SW-trending fault that accommodates the stretching of the lithosphere caused by a backward retreat of the Calabrian arc. The dynamics of the Calabrian arc controls the temporal occurrence of earthquakes in the Southern Apennines and in Sicily. By means of a detailed statistical approach, we identified a significant correlation between seismic events occurring in different subsets of this geodynamic domain: seismicity changes in the Southern Apennines follow those in the Calabrian arc after 18-21 years, while seismicity changes in Sicily follow those in the Calabrian arc after 8-10 years. The seismicity changes in these three areas appear also to have affected the eruptive activity of Vesuvius in the period 1631-1944. The major effusive-explosive eruptions of this period followed the seismicity changes in the Southern Apennines after 6-13 years and those in the Calabrian arc after 36-39 years. From a tectonic point of view, this indicates a direct link between the eruptive activity of Vesuvius and the dynamics of the Calabrian arc. The backward retreat of the arc produces strain pulses propagating to adjacent areas. From a volcanological point of view, we speculate that the arrival of an extension strain pulse in the area of Vesuvius may trigger the fast movement of magma-filled cracks that stay in unstable equilibrium in the roots of the volcano. © 1993.