A method for engineering-geological mapping: application to the Arezzo and Lucca provinces (Tuscany, Italy)

Lithological and geomechanical characters of outcropping rocks are relevant inputs for those applications involving geological issues. For instance, such information are used to implement spatial planning actions/rules influencing land use and transport infrastructures. The same data may also be used when mapping landslide susceptibility/hazard and preparing for landslide risk management. Many geomechanical classification systems for rock masses have been developed for engineering-geological applications (DEERE, 1963; BIENIAWSKI, 1973; BARTON et alii, 1974; HOEK, 1994). Nevertheless, these are site-specific systems or they are applied for specific engineering works (e.g. tunnels), so they are not fully adequate for continuous representations of engineering-geological properties over wide (map scale) areas. In this work, we describe the implementation of a GIS integrating lithological-geomechanical data collected in the field and laboratory with existing geological database to obtain an engineering-geological map at the scale of 1:10,000 for the provinces of Arezzo and Lucca (Tuscany, Italy). The study area is representative of different structural and lithologic settings within the Northern Apennines.