Seismotectonics of the Southern Apennines and Adriatic foreland: insights on active regional E-W shear zones from analogue modeling

摘要

The active tectonics at the front of the Southern Apennines and in the Adriatic foreland ischaracterized by E-W striking, right-lateral seismogenic faults, interpreted as reactivated inheriteddiscontinuities. The best studied among these is the Molise-Gondola shear zone (MGsz). Theinteraction of these shear zones with the Apennines chain is not yet clear. To address this openquestion we developed a set of scaled analogue experiments, aimed at analyzing: 1) how dextralstrike-slip motion along a pre-existing zone of weakness within the foreland propagates toward thesurface and affects the orogenic wedge; 2) the propagation of deformation as a function ofdisplacement; 3) any insights on the active tectonics of Southern Italy. Our results stress the primaryrole played by these inherited structures when reactivated, and confirm that regional E-W dextralshear zones are a plausible way of explaining the seismotectonic setting of the external areas of theSouthern Apennines.