The Submarine Boundaries of Mount Etna’s Unstable Southeastern Flank

Coastal and ocean island volcanoes are renowned for having unstable flanks. This can lead to flank deformation on a variety of temporal spatial scales ranging from slow creep catastrophic sector collapse. A large section these flanks is often below sea level, where information the volcano-tectonic structure ground limited. Consequently, kinematic models that attempt explain measured onshore associated with instability poorly constrained in offshore area. Here, we determine locations morpho-tectonic structures boundaries submerged southeastern Mount Etna (Italy). The integration new marine data (bathymetry, microbathymetry, seismicity, reflection seismic lines) published seafloor geodesy, allows identifying lineament north Catania Canyon as southern lateral boundary high level confidence. northern distal (seaward) less clear because no microbathymetric or geodetic available. Hypotheses their presented. Geophysical imaging suggests Timpe Fault System shallow second-order likely results extensional within moving flank. Evidence active uplift compression upslope amphitheater-shaped depression along subsidence Giarre Wedge block observed leads us propose this rotational slump, which moves top large-scale instability. shoreline-crossing structural assessment may now inform improve models.