ShakeMap Atlas of historical earthquakes in Italy

Italy has a rich history of studies on seismic history within the country and surrounding areas. Numerous archives and databases that focus on historical earthquake data, primarily intensity observations, are regularly updated. Macroseismic fields of past earthquakes are of foremost importance for evaluation of earthquake effects. To this purpose, we have implemented a strategy for generating historical earthquake shaking maps by adopting the ShakeMap service provided by the Istituto Nazionale di Geofisica e Vulcanologia (INGV). For our analysis, we used this dataset which contains over 12,000 intensity observations collected from the Italian Macroseismic Database (DBMI15). We selected 79 earthquakes with a magnitude of 6.0 or higher that occurred before 1972. The resulting shaking maps have been available on the INGV ShakeMap portal and the ASMI (Archivio Storico Macrosismico Italiano, Rovida et al., 2017) platform. To build the dataset, we adopted the configuration defined for the seismic settings in Italy, as described in the work of Michelini et al. (2020). We employed customized ground-motion-to-intensity conversion equations (GMICEs) and intensity prediction equations (IPEs). The conversion between ground motion and intensity was conducted using the regressions developed by Oliveti et al. (2022) and implemented in ShakeMap.