The 1930 earthquake and the town of Senigallia (Central Italy): an approach to seismic risk evaluation

Abstract

The town of Senigallia is located on the Adriatic coast of the Marche and Romagna regions (Central Italy), an area affected by offshore seismicity. This city was almost completely destroyed by an earthquake of IX degree intensity on the Mercalli-Cancani-Sieberg scale (MCS) on October 30, 1930. This quake is the most recent and the best documented. In particular, this shock was characterized by strong differences in the damage levels at a scale of hundreds and tens of metres. The geographic position of Senigallia at the mouth of a river and its soil conditions, similar to many other coastal historical and tourist centres in the region, make this earthquake an important case history, useful for a better understanding of the seismic risk of the entire coastal area. This note reports the first results of a study on the possible causes of the different damage levels. The research started with the history and town-planning evolution of Senigallia, then. the regional or local geological characteristics were considered by geological, geotechnical and geophysical investigations.