Geoarcheological and geomorphological evidences of recent ground vertical movements along the coast of Campania, southern Italy.

Geoarchaeological and geomorphic surveys in progress along the submerged coastland of Campania, are contributing to evaluate type, entity and rate of ground vertical movements responsible of archaeological heritage submersion as well as of littoral erosion. Discrimination of vertical motions linked to bradyseismic, tectonic, volcano-tectonic and subsidence phenomena, sometimes mutually interacting each other, plays a key role to understanding coastal morphoevolutionary dynamics since the last 3000 years. The ancient sea levels registered along the regional waterscapes show geomorphologic elements related to their settlement phases during the Holocene. Palaeo shorelines are often located at different depths, so they supply information about sea-level changes due to tectonic-eustatism and volcano-tectonic interactions. The study of archaeological structures, currently at depth not compatible with the sea level of their age, allows to deduce both palaeo-sealevel traces and ground vertical deformations in the analyzed case studies. In particular, different sectors of the Gulf of Naples were surveyed, among which (1) the Vesuvius coast (Portici-Castellammare di Stabia), (2) the Neapolitan-Phlegrean Fields area (Castel dell’Ovo-Posillipo and Baia-Cape Miseno), (3) the Phlegrean Islands (Procida, Vivara and Ischia), (4) the Gulf of Gaeta (Torregaveta and Sinuessa), and finally (5) the Island of Capri. Preliminary results highlight differential vertical movements mainly linked to (1) volcano-tectonic, (2, 3) bradyseismic, (4) complex vertical motions (bradyseism, subsidence, tectonics and volcano-tectonics interplay), and (5) coseismic or landsliding displacement. The highest values registered (i.e., -4.3 m along the Vesuvius coast, -4.5/-12 m along the Neapolitan-Phlegrean Fields coast, -3.5/-11 m at Torregaveta-Sinuessa, -9/-4.5 m in the islands of Vivara and Ischia, respectively), and recently -4.2 m in the Island of Capri, vary in the different morphostructural sectors of the gulfs of Naples and Gaeta, resulting higher than 2 mm/y which represents the average subsidence rate during the last 130 kyr (Tyrrhenian)