A comprehensive interpretative model of slow slip events on Mt. Etna’s eastern flank

Starting off from a review of previous literature on kinematic models of the unstable eastern
flank of Mt. Etna, we propose a new model. The model is based on our analysis of a large quantity of multidisciplinary
data deriving from an extensive and diverse network of INGV monitoring devices deployed
along the slopes of the volcano. Our analysis had a twofold objective: first, investigating the origin of the
recently observed slow-slip events on the eastern flank of Mt. Etna; and second, defining a general kinematic
model for the instability of this area of the volcano. To this end, we investigated the 2008–2013
period using data collected from different geochemical, geodetic, and seismic networks, integrated with
the tectonic and geologic features of the volcano and including the volcanic activity during the observation
period. The complex correlations between the large quantities of multidisciplinary data have given us the
opportunity to infer, as outlined in this work, that the fluids of volcanic origin and their interrelationship
with aquifers, tectonic and morphological features play a dominant role in the large scale instability of the
eastern flank of Mt. Etna. Furthermore, we suggest that changes in the strain distribution due to volcanic
inflation/deflation cycles are closely connected to changes in shallow depth fluid circulation. Finally, we propose
a general framework for both the short and long term modeling of the large flank displacements
observed.

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