Monitoring, Geomorphological Evolution and Slope Stability of Inca Citadel of Machu Picchu: Results from Italian INTERFRASI project

The Geology of Machu Picchu area is characterised by granitoid bodies that had been emplaced in the axial zones of the main rift system. Deformation of the granite, caused by cooling and tectonic phases, originated 4 main joint sets, regularly spaced (few decimetres to metres). Several slope instability phenomena have been identified and classified according to mechanism, material involved and state of activity. They are mainly related to rock falls, debris flows, rock slides and debris slides. Origin of phenomena is kinematically controlled by the structural setting and relationship with slope face (rock falls, rock slide and debris slides); the accumulated materials is the source for debris flow. Geomorphological evidences of deeper deformations are currently under investigation.