Geostructural and geognostic survey for a stability analysis of the calcareous cliff of Ispica (Hyblean plateau, southeastern Sicily)

The paper reports a geostructural and geognostic survey to evaluate the stability conditions of the highlyfractured calcareous cliff where the Monastery of the “Frati Minori” of Ispica is located. A large number offractures affect the whole cliff, resulting in dangerous conditions. In addition to a careful inspection of theslope to measure the structural discontinuities and identify rock blocks larger than 1 m3, cored boreholes wereextended to a depth of 30 m. The rock quality designation indicated that the rock quality varies from poor tofairly good. In this steep, vegetated area, the use of different investigation methods was necessary to determinethe physical, mechanical and geometric parameters necessary to plan the remedial works and measures toreduce the risk of rocks falling.