Georadar investigations to detect cavities in a historical town damaged by an earthquake of the past

摘要

This paper aims to highlight the use of the georadar as a useful prospectingtechnique to identify the areal density and the geometrical features of thegrottoes placed in a historical town characterised by high seismic hazard.The town considered here is Rionero in Vulture (Southern Italy) that was hitby several historical earthquakes, among which the 1930 Irpinia earthquake(Me=6.7, Is=VIII MCS).For this event a damage map was already available from a previous study(Gizzi and Masini, 2006). This map shows that some sectors of the townsuffered higher damage. One factor causing the uneven distribution of theeffects is considered to be the presence of grottoes.To strengthen this work hypothesis it was necessary to in-depth investigatethe subsoil of Rionero in Vulture. Therefore, geophysical data werecorrelated and integrated with data obtained from field surveys andhistorical documentary sources. All these investigations allowed to obtainmore insights about the influences of the man-made caves on seismic damage.