Feasibility and Problems in modeling rock faces for hazard mapping

ABSTRACT: In the paper we focus on the application of TLS to carry out the geometric surveying of rock faces to derive their DSM for simulating possible paths of falling rocks and then drawing hazard maps. After a general overview about the state-of-the-art of laser scanning tecniques applied to geological field, some operational addresses to people interested in this specific application are given. On the opinion of the author, the surveying of rock faces is one of the tasks which has taken major advantage by the appearance of TLSs, because they allow to get a DSM in a shorter time and with higher accuracy and resolution with respect to other topographicand photogrammetric methods, considering the degree of automation as well. In the second part of the paper three real experiences recently carried out in the Italian Prealps are presented. Each of them would like to give to the community the workflow of theapplication itself, so that practitioners could be apply the same method in their practical cases. However, main drawbacks areunderlined and some guidelines for further developements proposed.