169 research outputs found

    EFFECTS OF EARTHQUAKES ON THE MINOAN «ROYAL VILLA» AT HAGHIA TRIADA (CRETE)

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    Examination of damages affecting the buildings of the archaeological site of Haghia Triada (southern Crete), suggests that this Minoan settlement was probably destroyed by a major seismic event characterized by MKS intensities of IX-X and occurred in the Neo-palatial (1450 B.C.) periods. Geological and morphological studies carried out in the neighbouring areas show the occurrence of E-W trending Quaternary normal fault segments (Spili and Haghia Galini faults) that control the present topography and morphology, and exhibit steep young scarps mostly Holocene in age. These fault segments are related to a NW-SE extension direction which is consistent with that indicated by the available focal mechanisms of the earthquakes occurring in this area in the last 50 years. Combining structural and seismic data we can infer that the Spili and Haghia Galini fault segments could represent good candidates to be considered active faults generating large earthquakes (M~6.5) that were responsible for the damages of Haghia Triada. This hypothesis suggests that the Minoan palatial centres were destroyed by several large earthquakes related to ruptures along distinct fault segments rather than by a single catastrophic event that caused the abrupt destruction of the Minoan civilisation in the eastern Mediterranean

    Geological hazard in the central Mediterranean area

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    The present-day tectonic framework of the central Mediterranean area is the result of the Neogene-quaternary geodynamic processes related to the ca. N-S Africa-Europe convergence. This area is currently affected by large earthquakes and by local volcanic activity, mostly related to extensional or oblique-slip tectonics. The main regional feature in the area is a prominent fault belt that runs more or less continuously for a length of about 200km from the central sector of the Aeolian archipelago (Aeolian- Tindari fault system), along the Mount Etna coastline as far as the Hyblean-Malta offshore (Alfeo–Etna and Malta Escarpment fault systems), connecting southwards with the Sicily Channel rift systems.peer-reviewe

    Site effects on fault-zone : results from ambient noise measurements

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    It is well known that fault zones are generally characterized by a highly fractured low-velocity belt (damage zone), hundreds of meter wide, bounded by higher-velocity area (host rock) that can broaden for some kilometres (Ben-Zion et al,. 2003; Ben-Zion and Sammis, 2003, 2009 and references therein). Such geometrical setting and impedance contrast is in principle proficient to produce local amplification of ground motion (Peng and Ben-Zion, 2006; Calderoni et al., 2010; Cultrera et al., 2003; Seeber et al., 2000), as well as to support the development of fault zone trapped waves. There is a large number of papers that describe propagation properties of fault-guided waves (e.g., Li et al., 1994; Mizuno, Nishigami, 2006) in terms of ground motion amplification having a propensity to be maximum along the fault-parallel direction. These observations, both in theoretical and experimental approaches deal with almost pure strike slip faults such as the S. Andreas and the Anatolian faults (see Li et al., 2000; Ben Zion et al., 2003). Studies about local seismic response nearby fault zones have been performed in Italy and in California by Cultrera et al. (2003), Calderoni et al. (2010), Pischiutta et al. (2012) who observed evidences of ground motion amplification in the fault zone environments and strong directional effects with high angle to the fault strike. Similar studies, performed by Rigano et al. (2008) and Di Giulio et al. (2009) documented the presence of a systematic polarization of horizontal ground motion, near faults located on the eastern part of the Etnean area, that was never coincident with the strike of the tectonic structures. These directional effects were observed both during local and regional earthquakes, as well as using ambient noise measurements, therefore suggesting the use of microtremors for investigating ground motion polarization properties along and across the main tectonic structures of all the volcanic area. All the observations showed evidence of directional amplifications not parallel to the fault strike, as would have been expected for trapped waves. In the present study, the results of new measurements are shown and discussed. The data were recorded in newly investigated tectonic structures of the volcano located both on the western flank of Mt. Etna (Ragalna fault system) and on the eastern flank of the volcano (Piedimonte fault) as well as in a non-volcanic area (Malta Island), located in the Hyblean foreland. Moreover, several measurements were performed in areas significantly distant from the studied tectonic structures (Piano dei Grilli and Malta area), in order to observe how directional effects can change at increasing distance from the fault lines.peer-reviewe

    Terrestrial Laser Scanner techniques in the assessment of tsunami impact on the Maddalena peninsula (south-eastern Sicily, Italy)

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    The coastline of the Maddalena peninsula (south-eastern Sicily, Italy) is characterised by the occurrence of a boulder field associated to an extended soil stripping area and by a gravel/sandy berm. The accumulation of the boulders has been mostly correlated to the impact of the December 28, 1908 tsunami wave. The use of Terrestrial Laser Scanner survey techniques, associated to Differential Global Position System determinations, permits to obtain new data for the assessment of tsunami impact on this coastal area. The computing of the surveyed data using the most recent equations is a useful tool in order to estimate the theoretic inundation limit and to reconstruct its variability in function of the boulders size and of the coastal topography. Moreover, the entire new data set allows to confirm that the hypothesis of the tsunami impact is the most reasonable to explain the occurrence of boulders weighing up to 50 tons on the Maddalena peninsula

    Giant endobronchial hamartoma resected by fiberoptic bronchoscopy electrosurgical snaring

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    Less than 1% of lung neoplasms are represented by benign tumors. Among these, hamartomas are the most common with an incidence between 0.025% and 0.32%. In relation to the localization, hamartomas are divided into intraparenchymal and endobronchial

    Active deformation evidence in the offshore of western Calabria (southern Tyrrhenian Sea) from ultra-resolution multichannel seismic reflection data: results from the Gulf of Sant'Eufemia

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    An ultra-resolution, multichannel seismic reflection data set was collected during an oceanographic cruise organised in the frame of the “Earthquake Potential of Active Faults using offshore Geological and Morphological Indicators” (EPAF) project, which was founded by the Scientific and Technological Cooperation (Scientific Track 2017) between the Italian Ministry of Foreign Affairs and International Cooperation and the Ministry of Science, Technology and Space of the State of Israel. The data acquisition approach was based on innovative technologies for the offshore imaging of stratigraphy and structures along continental margins with a horizontal and vertical resolution at decimetric scale. In this work, we present the methodology used for the 2D HR-seismic reflection data acquisition and the preliminary interpretation of the data set. The 2D seismic data were acquired onboard the R/V Atlante by using an innovative data acquisition equipment composed by a dual-sources Sparker system and one HR 48-channel, slant streamers, with group spacing variable from 1 to 2 meters, at 10 kHz sampling rate. An innovative navigation system was used to perform all necessary computations to determining real-time positions of sources and receivers. The resolution of the seismic profiles obtained from this experiment is remarkable high respect to previously acquired seismic data for both scientific and industrial purposes. In addition to the seismic imaging, gravity core data were also collected for sedimentological analysis and to give a chronological constraint using radiocarbon datings to the shallower reflectors. The investigated area is located in the western offshore sector of the Calabrian Arc (southern Tyrrhenian Sea) where previous research works, based on multichannel seismic profiles coupled with Chirp profiles, have documented the presence of an active fault system. One of the identified faults was tentatively considered as the source of the Mw 7, 8 September 1905 seismic event that hit with highest macroseismic intensities the western part of central Calabria, and was followed by a tsunami that inundated the coastline between Capo Vaticano and the Angitola plain. On this basis, the earthquake was considered to have a source at sea, but so far, the location, geometry and kinematics of the causative fault are still poorly understood. In this study we provide preliminary results of the most technologically advanced ultra-high-resolution geophysical method used to reveal the 3D faulting pattern, the late Quaternary slip rate and the earthquake potential of the marine fault system located close to the densely populated west coast of Calabria

    New evidence of MIS 3 relative sea level changes from the Messina Strait, Calabria (Italy)

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    © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Antonioli, F., Calcagnile, L., Ferranti, L., Mastronuzzi, G., Monaco, C., Orru, P., Quarta, G., Pepe, F., Scardino, G., Scicchitano, G., Stocchi, P., & Taviani, M. New evidence of MIS 3 relative sea level changes from the Messina Strait, Calabria (Italy). Water, 13(19), (2021): 2647, https://doi.org/10.3390/w13192647.Investigation of sea-level positions during the highly-dynamic Marine Isotope Stage 3 (MIS 3: 29–61 kyrs BP) proves difficult because: (i) in stable and subsiding areas, coeval coastal sediments are currently submerged at depths of few to several tens of meters below the present sea level; (ii) in uplifting areas, the preservation of geomorphic features and sedimentary records is limited due to the erosion occurred during the Last Glacial Maximum (LGM) with sea level at a depth of −130 m, followed by marine transgression that determined the development of ravinement surfaces. This study discusses previous research in the Mediterranean and elsewhere, and describes new fossiliferous marine deposits overlaying the metamorphic bedrock at Cannitello (Calabria, Italy). Radiocarbon ages of marine shells (about 43 kyrs cal BP) indicate that these deposits, presently between 28 and 30 m above sea level, formed during MIS 3.1. Elevation correction of the Cannitello outcrops (considered in an intermediate-to-far-field position with respect to the ice sheet) with the local vertical tectonic rate and Glacial Isostatic Adjustment (GIA) rate allows the proposal of a revision of the eustatic depth for this highstand. Our results are consistent with recently proposed estimates based on a novel ice sheet modelling technique.This research received no external funding

    An unusual evolution of pneumonia in a child

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    Pleural empyema represents a severe complication of community acquired pneumonia with an incidence of 0.6% among hospitalized children.  Clinical manifestations of picture may be different in infants and young children and it should always be suspected in a child with pneumonia without significant clinical improvement after 48 hours of antibiotic treatment.  The most common microorganism associated with empyema is Streptococcus pneumoniae, especially in children under 5 years of age. Chest radiograph is the gold standard for diagnosis but chest ultrasonography,  and in some cases chestCT,  may be necessary to study features and evolution of the pleural fluid in order to guide therapeutic choices.  In most cases small pleural empyema responds to antibiotics alone. However in severe and extensive cases, drainage and invasive treatments, like video-assisted thoracic surgery (VATS) and thoracotomy, became necessary.  Due to the early start of antibiotic therapy, blood and pleural fluid cultures may result negative; in these cases only the use of molecular techniques, like polymerase chain reaction in biological fluids, may determine the etiology of the infection.  Here we report the case of previously healthy 8-years-old boy with an important and severe pleural empyema as a complication of S. Pneumoniae pneumonia, that did not respond to antibiotic therapy and thoracocentesis and for which decortication has been necessary. In our patient only molecular analysis on pleuric fluid has allowed us to define the etiology of the process

    Brief Communication Co-seismic displacement on October 26 and 30, 2016 (M<sub>w</sub> 5.9 and 6.5) – earthquakes in central Italy from the analysis of discrete GNSS network

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    &lt;p&gt;&lt;strong&gt;Abstract.&lt;/strong&gt; On October 26&lt;sup&gt;th&lt;/sup&gt; 2016, immediately north of the epicentral area affected by the M&lt;sub&gt;w&lt;/sub&gt; 6.0, August 24&lt;sup&gt;th&lt;/sup&gt; earthquake, a strong earthquake (&lt;b&gt;&lt;i&gt;M&lt;/i&gt;&lt;/b&gt;&lt;sub&gt;w&lt;/sub&gt;&amp;#8201;=&amp;#8201;5.9), with a focal mechanism showing W-dipping normal faulting, occurred at the boundary between Marche and Umbria regions (central Apennines, Italy). Four days later (on October 30&lt;sup&gt;th&lt;/sup&gt;), the main-shock (&lt;b&gt;&lt;i&gt;M&lt;/i&gt;&lt;/b&gt;&lt;sub&gt;w&lt;/sub&gt;&amp;#8201;=&amp;#8201;6.5) of the whole seismic sequence occurred in the same area. The central Apennines are characterized by northeast-verging thrust-propagation folds, involving Mesozoic- Tertiary sedimentary successions. During the 2016 sequence, coseismic deformation has been recorded at the rear of the Sibillini Thrust which separates the main mountain chain from the Marche-Abruzzi foothills (Fig. 1). This contractional structure has been partly dissected and/or inverted by NNW-SSE trending Quaternary normal and oblique-slip faults. The major event (October 30) induced extensive geological effects at the surface and structural damages in the broader epicentral area up to a distance of 30&amp;#8201;km. According to the report of the Istituto Nazionale di Geofisica e Vulcanologia (SUMMARY REPORT ON THE 30 OCTOBER, 2016 EARTHQUAKE IN CENTRAL ITALY Mw 6.5, Gruppo di Lavoro INGV sul Terremoto in centro Italia 10 November 2016), the hypocenter of major event was located at 42.8322&amp;#176;&amp;#8201;N, 13.1107&amp;#176;&amp;#8201;E at a depth of 9.2&amp;#8201;km (Figs. 1 and 2). Following the August seismic events, we installed five new geodetic points located on both sides of the principal fracture zone and carried out two campaigns of GNSS measurements, the first one at the end of September (30-09/02-10, 2016), the second one early November (11/13-11, 2016) that covered the period of the October events. &lt;br&gt;&lt;br&gt; In this brief communication, we provide the results of our geodetic campaigns that registered the co- seismic displacement occurred in the period between doy (day of year) 2016/274 and doy 2016/318, therefore documenting the two latter major shocks. We also compare our results with the available surface deformation field of the broader area obtained on the basis of the DInSAR technique and particularly the elaboration realized by CNR-IREA of Sentinel-1 radar imaging of Copernicus European Program of 26/10&amp;#8211;1/11 (&lt;a href=&quot; http://www.irea.cnr.it/index.php?option=com_k2&amp;view=item&amp;id=761:nuovi-risultati-sul-terremoto- del-30-ottobre-2016-ottenuti-dai-radar-dei-satelliti-sentinel-1&quot;target=&quot;_blank&quot;&gt;http://www.irea.cnr.it/index.php?option=com_k2&amp;view=item&amp;id=761:nuovi-risultati-sul-terremoto- del-30-ottobre-2016-ottenuti-dai-radar-dei-satelliti-sentinel-1&lt;/a&gt;). The comparison shows an overall good fit. It&amp;#8217;s worth to note that these earthquakes occurred in a sector of the Central Apennines characterized by high geodetic strain-rates (e.g., D&amp;#8217;Agostino 2014), where several continuous GNSS stations are operating.&lt;/p&gt
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