Holocene vertical deformation along the coastal sector of Mt. Etna volcano (eastern Sicily, Italy): implications on the time-space constrains of the volcano lateral sliding.

Abstract

A detailed survey of morphological and biological markers of paleo-shorelines has been carried out alongthe coastal sector of Mt. Etna volcano (eastern Sicily, Italy), in order to better define causes and timing ofvertical deformation. We have mapped markers of raised Holocene shorelines, which are represented bybeach rocks, wave-cut platforms, balanid, vermetid and algal rims. The timing of coastal uplift has beendetermined by radiocarbon dating of shells collected from the raised paleo-shorelines and, to correctlyassess the total amount of tectonic uplift of the coast during the Late Holocene, we have compared theelevation-age data of sampled shells to the local curve of Holocene sea-level rise. Taking into accountthe nominal elevation of the associated paleo-shorelines, an uplift rate of 2.5–3.0 mm/year has beenestimated for the last 6–7 ka. This general process of uplifting is only locally interrupted by subsidencerelated to flank sliding of the volcanic edifice, measured at docks and other manmade structures, and byacceleration along the hinge of an active anticline and at the footwall of an active fault. Based on this newdata we suggest more precise time–space constraints for the dynamics of the lower eastern flank of Mt.Etna volcano.