Laser Scanning Application for Geostructural analysis of Tuffaceous Coastal Cliffs: the case of Punta Epitaffio, Pozzuoli Bay, Italy

Abstract

This study presents the results of a Terrestrial Laser Scanner (TLS) application aimed at characterizing the structural pattern of Punta Epitaffio tuffaceous coastal cliff, Pozzuoli Bay, Eastern Tyrrhenian margin. The study site is located in the Campi Flegrei, an active volcanic caldera, characterized by dense urbanization, near the town of Naples, Italy. The 3D digital model of the Punta Epitaffio cliff derived from TLS data, provided a base for the classification of rock discontinuities by geostatistical analysis. In particular, the work flow of geostructural data processing included: 1) statistical analysis of spatial orientation of the facets of the 3D mesh derived by the TLS survey; 2) extraction of the best-fit attitudes (dip and dip direction) of discontinuity sets for each sub-planar patch of the rock face; 3) cluster analysis of best-fit structural discontinuities; 4) definition of all the discontinuity sets and geo-structural classification of 3D model facets; 5) kinematic analysis for the definition of possible failure mechanisms. Kinematic analysis took into account primarily structurally-controlled failure mechanisms (planar sliding, wedge sliding, flexural toppling, and direct toppling). The method illustrated in this research can be extensively applied to identify unstable areas along tuffaceous coastal cliffs and define shape and volume of rocks potentially involved by failures.