Geologia Urbana: itinerari in centro città per scoprire la geodiversità litologica

During the last years the interest towards urban areas as possible sites for educational activities concerning the Earth Sciences has been growing. The "Urban Geology" project developed by the Earth Sciences Department of the Universita degli Studi di Milano offers to high school teachers a model of a low-cost outdoor geological activity, with a particular focus on the importance of rocks as georesources and heritage stones in architecture. In a first phase, a pilot itinerary in the centre of Milan for discovering rocks in architecture was structured involving the undergraduate students of Natural Sciences and then proposed to teachers attending the TFA (Tirocinio Formativo Attivo) and in the frame of the "Piano Lauree Scientifiche". The Milan city centre is characterized by a lithological geodiversity that allows the observation of a great number of rocks of different origin and provenance, most of which are also widespread in the neighbouring cities. For each of the identified rocks, a short guide is made available to the teachers, with lithological description, petrographic classification and additional information on the origin, provenance and use in historical buildings. The guide may be used as preparatory material before the guided excursion, or as a support for more detailed studies after the visit, also offering ideas for interdisciplinary connections (art and architecture, history, economy). The supplied material may also help the teachers in organizing their own itinerary. The itinerary was proposed as didactic activity guided by Department tutors to high school classes (around 190 students up to now), as well as to the general public during the "Settimana del Pianeta Terra 2018" (80 participants). After the first positive experiences with the guided excursion, the project was further developed in the framework of the "Progetti Alternanza Scuola - Lavoro" (School - Work Alternance Projects) and was carried out by a total of 75 students from high schools located in Milan, San Donato Milanese, Bergamo and Lecco. The data collection on the field was performed using a specific multimedial tool, the GeoODK Collect App (http://ona.io/mzucali; http://ona.io/ibollati) for Smartphone. Through such projects, groups of students were able to create itineraries of Urban Geology in their own cities, illustrate their work to the public and share the data online. A workflow to reproduce the activity also in other areas is finally proposed.