Late-Quaternary ancient shorelines at Lipari (Aeolian Islands): stratigraphical constraints to reconstruct geological evolution and vertical movements

Indicators of three fossil shorelines, located at elevations of 43–45 m asl (I order), 23–27 m (II order) and about 12 m (III order), are recognized on the island of Lipari. Detailed evaluation of the stratigraphic relationships to the volcanic substratum allows their correlation with Late-Quaternary eustatic highstands of Tyrrhenian age, corresponding to marine oxygen isotope substages 5e (124 ka), 5c (100 ka) and 5a (81 ka). Marine deposits related to the ancient shorelines represent useful stratigraphic markers, as related unconformities constrain the geological evolution of Lipari. This is interpreted as a result of two main stages of volcanic activity (pre- and post- Tyrrhenian) spaced out by one stage characterized by prevalent marine erosional episodes ( Tyrrhenian). Chronological and altimetrical data concerning the ancient shorelines have been used to estimate the vertical mobility of the volcanic edifice of Lipari, which is characterized by a continuous uplift at an average rate of 0.34 mm/a during the last 125 ka: this estimation is fully concordant with the values obtained, during the same time period, from the nearby islands of Filicudi (0.31 mm/a) and Salina (0.36 mm/a), suggesting a similar uplift trend induced by the prevalence of regional tectonic processes.