0000000000399371
AUTHOR
A. Bambina
Interazione tra processi geomorfologici che coinvolgono il suolo e condizioni di rischio geoambientale
Lo studio dei fenomeni di instabilità superficiale risulta di particolare interesse in quanto molto spesso tale tipologia di dissesto produce gravi danni alle strutture antropiche e, talvolta, anche perdite di vite umane. Nonostante la modesta massa di terreno mobilizzata, queste frane possiedono una elevata pericolosità dovuta principalmente alla loro forza d’urto; i danni più frequenti riguardano le strade ed i relativi muri in calcestruzzo o in pietra che subiscono forti spinte laterali che ne provocano il ribaltamento. In alcuni casi possono causare anche gravi lesioni agli edifici, sfondando i muri posti sulla traiettoria della massa in movimento, provocando anche delle vittime; esempi…
LARGE LANDSLIDES AND NEOTECTONICS: A CASE STUDY IN WESTERN SICILY
The study area is located in the western sector of the Sicanian Mounts where the superimposition, consequence of the Miocene and Lower Pliocene tectonic transpressive phases, of different geologic bodies, having vergence to the southern quadrants, can be observed. In this area, the neo-autochthonous deposits are given by marly-clayey sediments of middle-upper Pliocene, pertaining to the “Marnoso-arenacea” Formation of the Belice Valley, and by Pleistocene calcarenites. The recent extensional tectonic crisis (neotectonics) have further dissected and dismembered the original structural edifice, involving also the Pleistocene calcarenites, which show tectonic displacements mainly NE – SW orien…
GENESIS AND GEOMORPHOLOGICAL EVOLUTION OF DEEP-SEATED GRAVITATIONAL SLOPE DEFORMATIONS: AN EXAMPLE OF DATING IN WESTERN SICILY
The study area lies in the westernmost part of the Sicani Mountain range where a superposition of SE-trending, stacked, geological bodies crops out. this structure is the result of transpressive tectonic phases of Miocene and Lower Pliocene age. The neo-autochthon outcrops are made up of clay–marly deposits of the Middle–Upper Pliocene, and of calcarenites of Pleistocene age. The extensional Quaternary tectonic phases later dissected and dismembered the original structure, thus involving the calcarenites that show clear, mainly NE–SW oriented dislocations. Such calcarenites, which have a total thickness of about 80 metres, overlap the Belice marly-arenaceous formation. This determined favou…
Note illustrative alla carta geomorfologica della Tavoletta Menfi (Sicilia occidentale)
The present note is to describe the morphogenetic processes and the relative landforms that were recognized in the area represented by the 1: 25,000 scale IGMI topographic map named Tavoletta Menfi (Serie 25/V F. 266 IV NO). The geomorphological map was realized by using the classic methodology based on direct geological and geomorphological field surveys, integrating the acquired data with the analysis of 1:18,000 scale aerial photos taken in 1997. From the geological point of view the examined area is characterized by the outcropping of carbonate and terrigenous sediments. The great part of the territory is affected by landslide phenomena, of different sizes and activity degree, that show…