Marturano A.a,, Aiello G.b, Barra D.b, a
Somma-Vesuvius ground deformation over the last glacial cycle
a Istituto Nazionale di Geofisica e Vulcanologia, sez. Osservatorio Vesuviano, via Diocleziano 328, 80124 Napoli, Italy
b Dipartimento di Scienze della Terra, dell'Ambiente e delle Risorse - Università di Napoli Federico II, Largo San Mrcellino 10, 80136 Napoli, Italy
Vertical ground movements at Somma-Vesuvius during the last glacial cycle have been inferred from micropalaeontological and petrochemical analyses of rock samples from boreholes drilled at the archaeological sites of Herculaneum and Pompeii as well as on the apron of the volcano and the adjacent Sebeto and Sarno Valleys. Opposing movements occurred during the periods preceding and following the Last Glacial Maximum (LGM). The uplift began 20 ka ago with marine deposits rising several tens of metres up to 25 m a.s.l., recovering previous subsidence which occurred during the Late glacial period, suggesting a strict connection between volcano-tectonic and glacial cycles. Here we present the analysis of deposits predating the LGM, which confirms subsidence of the Campanian Plain where Mt. Somma-Vesuvius is located, shows variable surface loading effects and highlights the volcano-tectonic stages experienced by the volcano. The self-balancing mechanism of the volcanic system, evolving towards an explosive, subaerial activity 60 ka ago, is testified by a large ground oscillation in phase with sea level change during the last glacial cycle.
► Large ground oscillation in phase with sea level change is reconstructed. ► Near sea-level palaeoenvironment at 60 ka is detected. ► Volcanotectonic source of strain is identified.
Somma-Vesuvius; palaeoecology; crustal deformation; sea-level change correlation