1,635 research outputs found
A new dataset and empirical relationships between magnitude/intensity and epicentral distance for liquefaction in central-eastern Sicily
Strong earthquakes can trigger several phenomena inducing soil deformation, such as liquefaction, ground fracturing
and landslides, which can often cause more damage than the seismic shaking itself. A research performed
on numerous historical accounts reporting descriptions of seismogeological effects in central-eastern Sicily, allowed
the authors to update the previous liquefaction datasets. 75 liquefaction-induced phenomena observed in
26 sites, triggered by 14 earthquakes, have been used to define relationships between intensity/magnitude values
and epicentral distance from the liquefied sites. The proposed upper bound-curves, at regional scale for central-
eastern Sicily, are realized by using the updating liquefaction dataset and also the new CPTI04 Italian earthquake
parametric catalogue. These relationships can be useful in hazard assessment to evaluate the minimum energy
of an earthquake inducing liquefactions
Geological Evidence of Paleotsunamis at Torre degli Inglesi (northeast Sicily)
Two layers of fine sand of marine origin occur in a
sequence of organic rich colluvia in an archaeological
excavation at Torre degli Inglesi, on Capo Peloro, northeast
Sicily. Stratigraphic and micropaleontologic analyses
support the hypothesis that these layers are related to
deposition due to paleotsunami waves. Their ages are
constrained both with radiocarbon and archaeological
datings. The age of the oldest layer is coincident with the
17 A.D. earthquake that hit Reggio Calabria but for which
no tsunami was previously reported. The age of the
youngest layer can be only constrained in the range 3rd–
19th century and is tentatively associated to the 6 Feb. 1783
event
Discrimination of tsunami sources (Earthquake vs. Landslide) on the basis of historical data in Eastern Sicily and southern Calabria
The source mechanisms responsible for large historical tsunamis that
have struck eastern Sicily and southern Calabria are a topic of robust debate. We have
compiled a database of historical coeval descriptions of three large tsunamis: 11 January
1693, 6 February 1783, and 28 December 1908. By using accounts of run-up and
inundation and employing an approach proposed by Okal and Synolakis in 2004, we
can provide discriminants to define the nature of the near-field tsunami sources (fault
dislocation or landslide).
Historical reports for the 1908 event describe affected localities, maximum runups,
and inundation areas. However, for the 1693 and 1783 tsunamis, reports are
limited to inundation and occasional run-up estimates. We calculate run-up values
for these events using available relations between inundation and run-up. We
employed the model of Okal and Synolakis to the obtained profiles of tsunami
run-up along the inundated shorelines. The 1908 run-up data distribution confirms
that the tsunami is compatible with a seismic dislocation source, whereas the
1783 data supports contemporary observations and recent offshore investigations suggesting
that the tsunami was produced by an earthquake-triggered submarine landslide.
Analysis of the 1693 event data suggests that the tsunami was generated
during a tectonic event and thus a seismogenic source should be found offshore
A unique 4000 year long geological record of multiple tsunami inundations in the Augusta Bay (eastern Sicily, Italy)
We present the geological evidence for a 4000 year long record of multiple tsunami inundations along the coast of the Augusta Bay (eastern Sicily)and discuss its implications. The research was carried out through a multi-theme approach which benefited from an extraordinarily long historical record that we used to guide detailed geomorphologic and geologic surveys, coring campaigns and laboratory analyses. Two sites, named the Augusta Hospital and Priolo Reserve, were selected and investigated in detail along the 25 km-long coastline of Augusta Bay. We found evidence for six (possibly seven) tsunami deposits; three of them may be tentatively associated with the 1693 and 365 AD Ionian Sea historical tsunamis and the ~3600 BP Santorini event. The other three (possibly four) deposits are evidence for unknown paleo-inundations dated at about 650–770 AD, 600–400 BC and 975–800 BC (at Augusta Hospital site), and 800–600 BC (at Priolo Reserve site). We use these ages to extend further back the historical record of tsunamis available for this coastal area. The exceptional number of tsunami deposits found with this study allowed us to derive an average geologic tsunami recurrence interval in the Augusta Bay of about 600 years for the past 4 ka. Conversely, the historical tsunami data for the past millennium suggest an average tsunami recurrence interval of about 250 years. This difference in the average recurrence intervals suggests that only the strongest inundations may leave recognizable geological signatures at the investigated sites (i.e. the evidence for the 1908 and 1169 tsunamis is missing) but also that the geomorphological setting of the site and its erosional/depositional history are critical aspects for the data recording. Thus, an average recurrence interval derived from the geological record should be considered as a minimum figure. The identification and age estimation of tsunami deposits represent a new and independent contribution to tsunami scenarios and modeling for coastal hazard assessment in Civil Protection applications. Furthermore, our study cases provide new elements on tsunami deposit recognition related to exceptionally large events that occurred in the Aegean Sea
Characterisation of flow dynamics within and around an isolated forest, through measurements and numerical simulations
The case study of ‘Bosco Fontana’, a densely-vegetated forest located in the north of Italy, is analysed both
experimentally and numerically to characterise the internal ventilation of a finite forest with a vertically
non-homogeneous canopy. Measurements allow for the evaluation of the turbulent exchange across the forest
canopy. The case study is then reproduced numerically via a two-dimensional RANS simulation, successfully
validated against experimental data. The analysis of the internal ventilation leads to the identification of
seven regions of motion along the predominate-wind direction, for whose definition a new in-canopy stability
parameter was introduced. In the vertical direction, the non-homogeneity of the canopy leads to the separation
of the canopy layer into an upper foliage layer and a lower bush layer, characterised respectively by an
increasing streamwise velocity and turbulence intensity, and a weak backflow. The conclusions report an
improved description of the dynamic layer and regions of motion presented in the literature
Geological evidence for paleotsunamis along eastern Sicily (Italy): an overview
Abstract. We present geological evidence for paleotsunamis along the ~230 km-long coast of eastern Sicily (Italy); combining this information with historical data, we reconstruct a unique history of tsunami inundations. We integrate data on 38 paleotsunami deposits (from fine sand layers to boulders) collected at 11 sites (one offshore). The geological data record traces of large tsunamis which have occurred during the past 4 millennia. Chronological constrains include 14C, 210Pb and 137Cs, OSL and tephrochronology. When compatible, the age of the paleotsunami deposits is associated to historical events, but it is also used to highlight unknown tsunamis. Average tsunami recurrence interval (between 320 and 840 yr) and minimum inland tsunami ingressions (often greater than the historical ones) were estimated at several sites. On the basis of this work, the tsunami catalogue is implemented by two unknown tsunamis which occurred during the first millennium BC and by one unknown regional tsunami, which occurred in 650–770 AD. By including this latter event in the eastern Sicily catalogue, we estimate an average recurrence interval for strong tsunamis of ca. 385 yr. Comparison and merging of historical and geological data can definitely contribute to a better understanding of regional and local tsunami potential and provides robust parameters to be used in tsunami hazard estimates
Composition of Ragusano Cheese During Aging
Ragusano cheese is a brine-salted pasta filata cheese. Composition changes during 12 mo of aging were determined. Historically, Ragusano cheese has been aged in caves at 14 to 16 degrees C with about 80 to 90% relative humidity. Cheeses (n = 132) included in our study of block-to-block variation were produced by 20 farmhouse cheese makers in the Hyblean plain region of the Province of Ragusa in Sicily. Mean initial cheese block weight was about 14 kg. The freshly formed blocks of cheese before brine salting contained about 45.35% moisture, 25.3% protein, and 25.4% fat, with a pH of 5.25. As result of the brining and aging process, a natural rind forms. After 12 mo of aging, the cheese contained about 33.6% moisture, 29.2% protein, 30.0% fat, and 4.4% salt with a pH of 5.54, but block-to-block variation was large. Both soluble nitrogen content and free fatty acid (FFA) content increased with age. The pH 4.6 acetate buffer and 12% TCA-soluble nitrogen as a percentage of total nitrogen were 16 and 10.7%, respectively, whereas the FFA content was about 643 mg/100 g of cheese at 180 d. Five blocks of cheese were selected at 180 d for a study of variation within block. Composition variation within block was large; the center had higher moisture and lower salt in moisture content than did the outside. Composition variation within blocks favored more proteolysis and softer texture in the center
Geological evidence for paleotsunamis along eastern Sicily (Italy): an overview
We present geological evidence for paleotsunamis
along the 230 km-long coast of eastern Sicily (Italy); combining
this information with historical data, we reconstruct
a unique history of tsunami inundations. We integrate data
on 38 paleotsunami deposits (from fine sand layers to boulders)
collected at 11 sites (one offshore). The geological data
record traces of large tsunamis which have occurred during
the past 4 millennia. Chronological constrains include 14C,
210Pb and 137Cs, OSL and tephrochronology. When compatible,
the age of the paleotsunami deposits is associated
to historical events, but it is also used to highlight unknown
tsunamis. Average tsunami recurrence interval (between 320
and 840 yr) and minimum inland tsunami ingressions (often
greater than the historical ones) were estimated at several
sites. On the basis of this work, the tsunami catalogue
is implemented by two unknown tsunamis which occurred
during the first millennium BC and by one unknown regional
tsunami, which occurred in 650–770 AD. By including this
latter event in the eastern Sicily catalogue, we estimate an
average recurrence interval for strong tsunamis of ca. 385 yr.
Comparison and merging of historical and geological data
can definitely contribute to a better understanding of regional
and local tsunami potential and provides robust parameters to
be used in tsunami hazard estimates
Historical, archeological and geological records of strong earthquakes at Capo Peloro (southern Italy)
During the 4th century AD southern Calabria and eastern Sicily were hit by an earthquake documented
by archaeoseismic analyses, which was interpreted by Guidoboni et al. (2000) as the predecessor of
the well-know 1908 earthquake, located in Messina Strait, whereas Galli and Bosi (2002) interpreted
this event as the precedessor of the 1783 earthquake.
The purpose of this paper is to find further evidence of these earthquakes in Messina area by a multidisciplinary
study aimed to recognize and date historical and paleo-earthquakes. For this goal we have
analyzed historical, archaeological and geological information of excavations performed at Capo
Peloro near the Torre del Faro village (Fig. 1) in the Torre degli Inglesi (English Tower), built on an
abandoned Roman tower
- …