Historical damage pattern and causes of differential damage: an approach based on combining geophysical prospecting, geological and historical-technical data

Abstract

We describe a multidisciplinary and interdisciplinary method to analyse the causes of differential macroseismic effects caused by an earthquake in a historical town. We illustrate the method with a case study based on analysing the damage caused by the 1930 Irpinia earthquake (Me=6.7) in Melfi, a town in southern Italy. A damage pattern map was already available for this site. <br><br> To understand the anomalies of Melfi damage, we used an integrated approach that combines geological surveys, geophysical prospecting and analysis of unpublished technical-historical data. <br><br> Geo-electrical prospecting was adopted to infer the geological set-up and to estimate the thickness of shallow deposits. The results of the geophysical surveys were compared with detailed geological information derived from both in situ surveys and boreholes. Finally, cross-correlation among these data and technical reports coeval to the earthquake allowed us to create a complete picture of the possible causes of uneven damage.