Asbestos and other fibrous minerals contained in the serpentinites of the Gimigliano-Mount Reventino Unit (Calabria,S-Italy)   总被引：1，自引：1，他引：0  

Andrea Bloise  Teresa Critelli  Manuela Catalano  Carmine Apollaro  Domenico Miriello  Alessandro Croce  Eugenio Barrese  Francesca Liberi  Eugenio Piluso  Caterina Rinaudo  Elena Belluso 《Environmental Earth Sciences》2014,71(8):3773-3786

Serpentinites are metamorphic rocks with good technological properties and valuable ornamental characteristics, which have been exploited since ancient times. Actually, their use is limited and monitored in several countries worldwide because they can contain fibrous asbestos minerals that may be carcinogenic. Furthermore, certain types of fibrous minerals can be confused with asbestos, and must therefore be carefully investigated. We have investigated the possible presence of the asbestos and non-asbestos fibrous phases contained in serpentinitic rocks in a meta-ophiolitic sequence from the Gimigliano-Mount Reventino Unit (Southern Italy), which had not been previously assessed. The detection and quantification of asbestos and the correct distinction of the fibrous non-asbestos minerals are very important not only from a scientific point of view, but also from a legislative one. This is especially the case for the administrative agencies that have to take decisions with regards to the implementation of public and occupational health protection measures (e.g., in road yards and quarry excavations). As a consequence of this, serpentinitic rock samples have been characterized in detail through X-ray powder diffraction, scanning and transmission electron microscopy combined with energy-dispersive spectrometry, analytical electron microscopy (SEM–EDS and TEM–AEM), differential scanning calorimetry, thermogravimetry and micro-Raman spectroscopy. Two kinds of asbestos and four kinds of non-asbestos fibrous silicates have been detected in the examined samples. In order of decreasing abundance these are polygonal serpentine, chrysotile, fibrous antigorite, tremolite, gedrite and magnesiohornblende. The size, morphology, crystallinity and chemical composition of the fibres were also discussed, in the light of the possible role these properties could play in the carcinogenic effect on human health.  相似文献   

Earthquakes in Switzerland and surrounding regions during 2009     

Nicholas Deichmann  John Clinton  Stephan Husen  Benjamin Edwards  Florian Haslinger  Donat Fäh  Domenico Giardini  Philipp Kästli  Urs Kradolfer  Iris Marschall  Stefan Wiemer 《Swiss Journal of Geoscience》2010,103(3):535-549

This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during 2009. During this period, 450 earthquakes and 68 quarry blasts were detected and located in the region under consideration. The three strongest events occurred about 15 km NW of Basel in southern Germany (M_L 4.2), near Wildhaus in the Toggenburg (M_L 4.0) and near Bivio in Graubünden (M_L 3.5). Although felt by the population, they were not reported to have caused any damage. With a total of 24 events with M_L ≥ 2.5, the seismic activity in the year 2009 was close to the average over the previous 34 years.  相似文献   

Water–gas dynamics and coastal land subsidence over Chioggia Mare field, northern Adriatic Sea     

Pietro Teatini  Domenico Baú  Giuseppe Gambolati 《Hydrogeology Journal》2000,8(5):462-479

A major development programme comprising 15 gas fields of the northern Adriatic Sea has recently been submitted to the Ministry of the Environment, VIA Committee for the assessment of the environmental impact, by ENI-Agip, the Italian national oil company. One of the largest reservoirs is Chioggia Mare, located about 10 km offshore of the Venetian littoral, with a burial depth of 1000–1400 m. The planned gas production from this field is expected to impact the shoreline stability with a potential threat to the city of Venice, 25 km northwest of the center of Chioggia Mare. To evaluate the risk of anthropogenic land subsidence due to gas withdrawal, a numerical model was developed that predicts the compaction of both the gas-bearing formations and the lateral/bottom aquifer (water drive) during a 13-year producing and a 12-year post-production period, and the transference of the deep compaction to the ground surface. To address the uncertainty of a few important hydromechanical parameters, several scenarios are simulated and the most pessimistic predictions obtained. The modeling results show that at most 1 cm of land subsidence over 25 years may be expected at the city of Chioggia, whereas Venice is not subject to settlement. If aquifer drawdown is mediated by water injection, land subsidence is arrested 5 km offshore, with the Chioggia littoral zone experiencing a rebound of 0.6–0.7 cm. Electronic Publication  相似文献   

Resistivity anomaly imaging by probability tomography   总被引：10，自引：0，他引：10  

Paolo Mauriello  & Domenico Patella 《Geophysical Prospecting》1999,47(3):411-429

Probability tomography is a new concept reflecting the inherently uncertain nature of any geophysical interpretation. The rationale of the new procedure is based on the fact that a measurable anomalous field, representing the response of a buried feature to a physical stimulation, can be approximated by a set of partial anomaly source contributions. These may be given a multiplicity of configurations to generate cumulative responses, which are all compatible with the observed data within the accuracy of measurement. The purpose of the new imaging procedure is the design of an occurrence probability space of elementary anomaly sources, located anywhere inside an explored underground volume. In geoelectrics, the decomposition is made within a regular resistivity lattice, using the Frechet derivatives of the electric potential weighted by resistivity difference coefficients. The typical tomography is a diffuse image of the resistivity difference probability pattern, that is quite different from the usual modelled geometry derived from standard inversion.  相似文献   

Preliminary prediction of damage to residential buildings following the 21st August 2017 Ischia earthquake     

Carlo Del Gaudio  Mariano Di Domenico  Paolo Ricci  Gerardo Mario Verderame 《Bulletin of Earthquake Engineering》2018,16(10):4607-4637

On August 21st, 2017, an earthquake with duration magnitude M_d?=?4.0 and epicentre in Casamicciola Terme hit Ischia island, in the South of Italy. This event caused two fatalities and dozens of injured people. Moreover, despite the low magnitude, the earthquake produced significant damages to masonry and reinforced concrete (RC) buildings, with some partial or complete collapse of structures, in a very limited area close to the epicentre, while even at small distance from the most damaged zone the earthquake was just felt by local people and tourists. In the days after the event, discussions concerning the destructive effects of such an earthquake arose in the scientific community—as also reported by local and national media. In this paper, the seismic history of Ischia island is recalled to show and explain the peculiarity of the August 21st earthquake, which is also described in terms of ground motion and response spectra characteristics. The results of the first surveys carried out in Casamicciola Terme are reported, together with appropriate pictures, to introduce and explain the observed damage state of masonry and RC buildings in the epicentral zone. Then, data from the 15th general census of the population and dwellings (ISTAT) is used to define vulnerability classes according to the classification of the European Macrosismic Scale (EMS-98) (Grünthal, 1998). Seismic damage scenarios are then evaluated combining macro-seismic intensity values obtained using an interpolation method starting from QUEST macro-seismic survey data (Azzaro et al., 2017 ) and fragility curves for A-to-D vulnerability classes and for five damage states, from DS0 (no damage) to DS5 (collapse) trough a Monte Carlo simulation technique. The distributions of Usable, Temporarily or Partially Unusable, and Unusable buildings, which are obtained by using relationships between damage and usability judgments obtained through post-earthquake damage data collected after past seismic events, result in very good accordance with those published in September 1st, 2017 by the Department of Civil Protection, regarding a dataset of about 600 buildings.  相似文献   

A discriminatory diagram of massive versus stratified deposits based on the sedimentation and bedload transportation rates. Experimental investigation and application to pyroclastic density currents     

Pierfrancesco Dellino  Fabio Dioguardi  Domenico Maria Doronzo  Daniela Mele 《Sedimentology》2020,67(4):2013-2039

Dense gas-particle jets similar to collapsing eruption columns were generated by large-scale experiments. The column collapse resulted in a ground-hugging current forming stratified layers with bedding similar to natural pyroclastic density current deposits. At the impact of the collapsing column on the ground, a thick, massive bed was formed due to a high sedimentation rate that dumped turbulence due to high clast concentration. Down-current, flow expansion favoured turbulence and dilute gas-particle current that formed thin rippled layers deposited under traction. Experiments fed with fine ash (median size 0·066 mm) formed deposits without tractional structures, because fine particles, as other sedimentary fine material, is cohesive and exposes a limited surface to the shear stress. Experimental outcomes show that massive beds are formed where the sedimentation rate per unit width S_rw exceeds the bedload transportation rate Q_b by two orders of magnitude. A lower ratio generates traction at the base of the flow and formation of shear structures that increase in wavelength and height with a decreasing flux. This study presents a diagram that provides a useful addition for facies analysis of pyroclastic density currents, provided that deposits representing sustained sedimentation can be identified in the field. In the diagram a decrease in the S_rw/Q_b ratio corresponds to an increase in bedform size. Application of the diagram for hazard assessment purposes allows the reconstruction of the mass eruption rate of the Agnano–Monte Spina eruption at Campi Flegrei, which is the main variable defining the intensity of past eruptions, and of the Bingham rheology of the massive underflow of the Mercato pyroclastic density current at Vesuvius.  相似文献