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Lalibela is located in the northern-central part of Ethiopia, approx. 600 km north of Addis Ababa in Northern Wollo, one of the most structural food deficit areas of the Amhara Region. The town, which has about 12000 inhabitants, is situated at an altitude of 2500 m (Fig. 26.1). In its center, a unique complex of 11 rock-hewn Christian Orthodox churches is loacted. The churches were cut out of the living rock some 800 years ago during the kingdom of King Lalibela (1167–1207) of the Zagwe dynasty. One of these churches, Biet Aba Libanos, is a monolithic church anchored to the rock from which it was carved. Two major damaging phenomena affect the church: weathering of volcanic tuff in the lower part of the edifice and sliding of the façade and lateral walls, as consequence of a prone discontinuity. A first destruction of the façade was already occurred in the past, as consequence of an old planar sliding, still in coincidence of the same joint. Presently, the walls prone to slide are the structures constructed to replace the original rock that collapsed during the slide as well as some of the original rock hewn lateral walls. Kinematical analysis and numerical modeling implemented, clearly evidence the hazardous conditions of the rock hewn church of Biet Aba Libanos and the need of a prompt and proper intervention. [ABSTRACT FROM AUTHOR]

The village of Craco (Basilicata, Italy), is being affected by severe landslide phenomena mainly due to the geological and geomorphological setting of the area. The village has been interested by a progressive abandon of the population after the occurrence in the time of landslides and earthquakes that caused the disruption of large portions of the urban settlement. Several landslide typologies can be recognized in the area: rock-falls in the upper part of the hill, rotational and translational earth slides, earth-flows, rock lateral spreading. The main purpose of the paper is to reconstruct the evolution of the geological and morphological dynamics acting on the southern slope of Craco, where the largest landslides occurred in the past. The analysis of deep landslide phenomena has been carried out with a multi-temporal geomorphological approach using analogical and digital photogrammetry on 4 different set of aerial photos (1954–1999). The analysis has stressed a progressive retrogression of the crown area in the upper portions of the hill that caused, in the recent past, the degradation or, in some cases, the complete disruption of part of the historical village, where most of cultural heritage was located. The reconstruction of the landslide evolution acting in this area can be very useful as model to transfer in other areas characterized by similar geological and morphological setting that may result in large landslide phenomena. The suggestion of correct mitigation strategies may help to prevent environmental and, consequently, social degradation of the territory. [ABSTRACT FROM AUTHOR]

The geology of Machu Picchu area is characterized 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 decimeters to meters). 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 are the source for debris flows. Geomorphological evidences of deeper deformations are currently under investigation. A low environmental impact monitoring system has been established on the area with the purpose to minimize equipments usage and, in the mean time, to collect reliable data on surface deformations. The monitoring network is based on a GPS, multitemporal laser scanner survey, Ground based Radar interferometry (GB-SAR) and Satellite Interferometric Synthetic Aperture Radar (InSAR). The preliminary results are partially confirming the field evidences of slope deformation but, in the mean time, they require a longer period of observations since the sliding processes are relatively slow. [ABSTRACT FROM AUTHOR]