Search results for "geologia"

Durability of calcarenitic hypogea in the underground cultural heritage of Palermo (Sicily)

2011

The paper deals with the stability conditions of hypogea, several hundred m 2 wide, dating from the Punic period to the XIX century, dug out of the calcarenitic table that makes up the bedrock of the Plain of Palermo in the Fossa della Garofala. This work concerns the influence that the shape of the hypogea and the characteristics of the lithotypes wields on the instability and decay phenomena taking place, by mean of laboratory tests on the calcarenite and parametric numerical models. The comparison between the numerical models and the actual instability phenomena validated the use of the empirical formula of Hoeck to the mechanical characterization of complex structured rock-mass in soft …

Landslide inventory and rockfall risk assessment of the Monte Pellegrino Oriented Nature Reserve area (Sicily)

2018

In the last 20 years the natural oriented reserve of Monte Pellegrino is affected by several rockfall events. This sector of the Northern Sicily is a strategic urban area and represent the most important element of both the religious and cultural tradition and landscape for the city of Palermo.The rockfalls are here the major natural threats and represent a relevant risk of people, structures and infrastructures and prevents the economic and social development that could be made by high tourist potential of the area. For the above mentioned reasons a detailed geological and geotechnical study in order to define a quantitative risk analysis is now being carried out, concurrently with the imp…

Exporting a Google Earth™ aided earthflow susceptibility model: a test in central Sicily

2012

Abstract In the framework of a regional landslide susceptibility study in southern Sicily, a test has been carried out in the Tumarrano river basin (about 80 km2) aimed at characterizing its landslide susceptibility conditions by exporting a ‘‘source model’’, defined and trained inside a limited (about 20 km2) representative sector (the ‘‘source area’’). Also, the possibility of exploiting Google Earth TM software and photo-images databank to produce the landslide archives has been checked. The susceptibility model was defined, according to a multivariate geostatistic approach based on the conditional analysis, using unique condition units (UCUs), which were obtained by combining four selec…

Geological and geomorphological aspects of the landslide of the Cathedral of Agrigento (Sicily-Italy)

2014

Measure of a limestone weathering degree using Laser Scanner.

2013

The weathering degree of the building materials and natural stones is generally quantified as the decrement of some mechanical features that can be measured experimentally by means of compressive tests or point load tests in the laboratory or Schmidt hammer tests carried out in situ. Such destructive or damaging tests are unacceptable in case of cultural heritage since even small amounts of damage must be avoided. This work shows a correlation between Schmidt hammer rebound values and the reflectivity that is detected by means of terrestrial scanner laser; therefore it allows assessing the weathering degree of buildings or stones in situ. The results demonstrate that such an investigation c…

The Latomiae of Syracuse: A Geotechnical Mapping Through Rock Reflectivity

2014

The archeological site of the Latomia del Paradiso (Syracuse) is endangered by severe instability phenomena due to the shape of walls and underground excava-tion related with the poor mechanical characteristics of the weathered and wet rock. The failure of huge blocks from the ceiling of the underground areas and the detaching of rock "flakes" from the walls surface make the geotechnical zon-ing particularly complex. the zoning is based on the characteristics of the rock wall surface that, in first approximation, can be distinguished in regularized sur-faces because of mining , and in irregular surfaces characterized by fracture prop-agation. The elaboration of reflectivity values obtained …

Measuring magnitude and rate of vertical movements in the offshore Capo Vaticano (W Calabria) using lowstand coastal prisms and wave-built terraces

2012

The magnitude and rate of vertical movements have been measured in the offshore Capo Vaticano (western Calabria) for the Late Pleistocene - Holocene on the basis of the depth of submerged coastal prism and associated wave-built terrace formed during the sea-level lowstand of the Last Glacial Maximum (LGM). Uplifted and submerged terraces have proved to be valuable recorders of vertical motion in many locations around the world (e.g. DICKINSON, 2001; WEBSTER et alii, 2004) as the depth of their tops appear to be controlled by the sea-level. In the eastern Tyrrhenian margins, depending on the hydraulic energy conditions (i.e. waves and wind-induced currents), the average water depth of terrac…

“Inner” and “outer” wedge-top sequences in the Late Miocene Sicilian Foreland Basin System; inferences from the Upper Tortonian – Lower Messinian Ter…

2010

Rock decay phenomena and collapse processes in the “Latomiae del Paradiso” in Syracuse (Sicily)

2014

The Latomiae (origin: Greek latomia, from laas, las stone plus –tomia tomy ) del Paradiso in Syracuse are Magna Graecia rock quarries, located in the coastal areas of Southern Italy and internationally renowned for their impressive environment. The few historical technical records do not help clarify the events that led to their current configuration since a series of instability phenomena occurred due to decay processes over time. Through a geotechnical back-analysis, this work highlights the failure phenomena, which may have led to the current configuration of the easterly side of the Latomiae del Paradiso. The back-analysis process was carried out by means of numerical modelling, support…

Facies Architecture and Evolution of a Cretaceous, Tectonically-Controlled, Carbonate Slope from Western Sicily (Italy)

2018

The stratigraphic architecture of a Cretaceous carbonate slope from north western Sicily (Italy) has been reconstructed on the basis of detailed field sections. The wire cut walls of a number of quarries that extract the Cretaceous limestones as ornamental stones allowed the mapping of the stratal architecture and lithologies at various scales. The vertical and lateral facies relationships in this about 1000 m thick depositional system account for a complex sedimentary dynamics along a carbonate platform escarpment that was strongly influenced by syn-sedimentary transtensional tectonics associated to magmatism. Although the original relationships with the carbonate platform were obscured by…