Search results for "Geomorfologia"
showing 10 items of 291 documents
Evaluating the effects of man-induced topographic changes in landscape structure on soil erosion by water: a case study in Sicily
2012
Sprofondamenti di origine antropica nell'area di Marsala (Sicilia occidentale) analizzati mediante rilievi in sito e analisi numerica dei processi di…
2013
The geo-hydrologic event in the Peloritan – Ionian area of 2009: debris-flow susceptibility assessment by means of forward logistic regression
2012
On the 1st of October 2009, the area centred on the village of Giampilieri (Messina), on the Ionian side of the Peloritan belt, suffered thousands of landslides activated in the time lapse of about five hours, which caused 36 victims, more than 100 injured and more than 0.5M€ of damage to structures. This unprecedented phenomenon was triggered by an exceptional meteorological event, recorded at the foothills with 250mm of rain in just 8 hours; this amount of rainfall was cumulated to two previous events (16/IX: 75mm; 23/IX: 190mm) for a total amount of more than 500mm in less than two weeks. Due to the peculiar triggering conditions a huge number of debris flows involved the shallow weather…
Dal tempo biblico al tempo geologico
2011
Primo contributo sui depositi argillosi a terra rossa dell'Abisso del Vento, Isnello (PA).
2004
Secondary minerals from halite caves in the Atacama Desert (Chile)
2017
In the past 15 years several expeditions by French, American and especially Italian cavers have surveyed over 15 km of salt cave passages in the Cordillera de la Sal, close to San Pedro de Atacama village (Atacama Desert, Northern Chile). Over 50 caves have been explored up to now at an elevation around 2,500 m asl. These karst systems are characterized by in-cave temperature of around 17 °C and a relative humidity always very low, with a maximum of 15%. This extreme aridity is due to the severe conditions of the area with only a couple millimeters annual rainfall and several years without rain. Currently the rare precipitation events are enough to allow the dissolution of the salt rock and…
Hypogenic caves of Sicily (Southern Italy)
2013
First results of a study on hypogenic caves in Sicily are presented. Inactive water-table sulphuric acid caves and 3D maze caves linked to rising of thermal waters rich in H2S were recognized. Cave patterns are guided by structural planes, medium and small scale morphological features are due mainly to condensation-corrosion processes. Calcite and gypsum represent the most common cave minerals. Different types of phosphates linked to the presence of large bat guano deposits were analyzed.
Secondary Minerals From Italian Sulfuric Acid Caves
2017
Italy is a country hosting a large number of hypogenic sulfuric acid (SAS) speleogenesis caves, mostly located along the Apennine chain, but also in Campania (along the coastline of Capo Palinuro), Apulia (along the coastline of Santa Cesarea Terme) and Sicily. Besides the typical morphologies related to their special geochemical origin (cupolas, replacement pockets, bubble trails, etc), these caves often host abundant secondary mineral deposits, mainly gypsum, being the result of the interaction between the sulfuric acid and the carbonate host rock. Native sulfur deposits are also well visible on the ceiling and roof, and peculiar sulfuric acid minerals such as jarosite, alunite, and other…
Analisi numerica dei processi di instabilità in cave sotterranee a Marsala (Sicilia occidentale)
2014
La presenza di estesi sistemi caveali in sotterraneo, utilizzati nel secolo scorso per l’estrazione di materiale da costruzione in diversi contesti del territorio italiano, di frequente determina situazioni di pericolo per l’ambiente antropizzato, a causa dello sviluppo di processi di instabilità, che possono propagarsi verso l’alto, sino a raggiungere la superficie. Specialmente nei casi in cui la memoria storica della presenza ed estensione delle cave sotterranee è andata persa, lo sviluppo urbanistico dei centri abitati nel corso degli ultimi decenni può avere determinato la realizzazione di abitazioni ed infrastrutture al di sopra, o nelle immediate vicinanze, di zone interessate da com…
An Approach for the Validation of a Coastal Erosion Vulnerability Index: An Application in Sicily
2022
In recent decades, coastal erosion phenomena have increased due to climate change. The increased frequency and intensity of extreme events and the poor sediment supply by anthropized river basins (dams, river weirs, culverts, etc.) have a crucial role in coastal erosion. Therefore, an integrated analysis of coastal erosion is crucial to produce detailed and accurate coastal erosion vulnerability information to support mitigation strategies. This research aimed to assess the erosion vulnerability of the Sicilian coast, also including a validation procedure of the obtained scenario. The coastal vulnerability was computed by means of the CeVI (Coastal Erosion Vulnerability Index) approach, whi…