DEVELOPMENT OF A GEOLOGICAL MODEL USEFUL FOR THE STUDY OF THE NATURAL HAZARDS IN URBAN ENVIRONMENTS: AN EXAMPLE FROM THE EASTERN SECTOR OF ROME (ITALY)

摘要

A detailed knowledge of the subsoil setting is an extremely important issue for a correct risk reduction policy, especially if dealing with urban areas hosting cultural heritage, that enhance risk conditions even under low geo-hazard levels, as in the case of Rome. In general terms, the reliability of risk assessments related to geo-hazards is strictly dependent on the resolution of the reference geological model. The here presented study exemplifies an integrated methodology aimed at refining the knowledge of the geological setting in such a peculiar environment as the city of Rome, where canonical approaches are limited by a substantial lack of outcrops and on-purpose geognostic campaigns can be time- and money-consuming. The methodology is based on a critical review of available geological, stratigraphic, archaeological, historical-archival data. The integration of such data, properly stored, managed and analyzed in a GIS environment, allowed us to better frame the geological setting of a wide sector in the eastern part of Rome, with particular focus on the identification of buried natural morphologies (i.e. valleys) strongly modified by the progressive urbanization and, more in general, on the assessment of the thickness of backfills, that often represent a critical geotechnical issue. As a result we obtained a detailed geological model that shows slight but significant differences with respect to the already available official maps, highlighting the necessity of in-depth analyses of already existing data from different sources in order to achieve thematic information useful for effective land management policies.