Occurrence of bottlenose dolphins Tursiops truncatus in natural gas fields of the northwestern Adriatic Sea     

Francesca Triossi  Trevor J. Willis  Daniela S. Pace 《Marine Ecology》2013,34(3):373-379

Common bottlenose dolphins, Tursiops truncatus, were surveyed in offshore gas fields off Ravenna, Italy, between Spring and Autumn, 2001–2005. These visual surveys provide the first density estimates of bottlenose dolphins in the Northwestern Adriatic Sea south of the Po River. Since no study has examined the distribution of bottlenose dolphins relative to gas platforms, when dolphins were encountered, their distance from the nearest gas platform was estimated and behaviour was assessed. Dolphins were sighted on ca. 36% of survey trips, which varied in duration from 1 to 6 h. Group size ranged from 1 to ~50 individuals, with no seasonal trend evident in the likelihood of encounter. Dolphin density was estimated to be approximately 80% higher within 750 m of gas platforms, relative to densities >750 m from platforms, although variability around the estimates was high. From a limited number of behavioural observations, slightly higher frequencies of feeding and milling behaviour were observed closer to gas platforms, whereas dolphins observed further away exhibited higher frequencies of socialising and travelling. Gas platforms are known to provide habitat for demersal fishes and act as aggregation points for pelagic fishes, and these data provide some support for the idea that bottlenose dolphins may utilise gas platforms opportunistically as feeding sites.  相似文献   

The emplacement of the Late Miocene Monte Capanne intrusion (Elba Island,Central Italy): constraints from magnetic fabric analyses     

Francesca?CifelliEmail author  Liliana?Minelli  Federico?Rossetti  Giorgia?Urru  Massimo?Mattei 《International Journal of Earth Sciences》2012,101(3):787-802

Anisotropy of magnetic susceptibility (AMS) analysis has been carried out in the thermometamorphic aureole surrounding the Late Miocene Monte Capanne pluton (Elba Island, Central Italy). The identification and separation of the main carriers of the magnetic susceptibility by low-temperature and high-field AMS measurements demonstrate that a correct knowledge of the magnetic fabric is needed in order to use AMS for tectonic interpretations. Magnetic fabric data, combined with structural data from the aureole, and their comparison with data from the pluton itself, were used to constraint the mode of pluton emplacement. Results document an intimate linkage between the magmatic flow pattern and the syn-metamorphic fabrics acquired during pluton emplacement in the host rocks. The magnetic/structural fabric in the aureole rocks is dominated by flattening deformation and no systematic relationship with any regional tectonic feature is observed. These results suggest that local processes induced by magma ascent in the upper crust might have played a primary role in space generation for pluton emplacement in the Tuscan Magmatic Province, suggesting a revaluation of the modes of pluton emplacement during the post-orogenic evolution of the northern Apennine system as a whole.  相似文献   

Vesta's mineralogical composition as revealed by the visible and infrared spectrometer on Dawn     

M. Cristina De Sanctis  Eleonora Ammannito  M. Teresa Capria  Fabrizio Capaccioni  Jean‐Philippe Combe  Alessandro Frigeri  Andrea Longobardo  Gianfranco Magni  Simone Marchi  Tom B. McCord  Ernesto Palomba  Federico Tosi  Francesca Zambon  Francesco Carraro  Sergio Fonte  Y. J. Li  Lucy A. McFadden  David W. Mittlefehldt  Carle M. Pieters  Ralf Jaumann  Katrin Stephan  Carol A. Raymond  Christopher T. Russell 《Meteoritics & planetary science》2013,48(11):2166-2184

The Dawn spacecraft mission has provided extensive new and detailed data on Vesta that confirm and strengthen the Vesta–howardite–eucrite–diogenite (HED) meteorite link and the concept that Vesta is differentiated, as derived from earlier telescopic observations. Here, we present results derived by newly calibrated spectra of Vesta. The comparison between data from the Dawn imaging spectrometer—VIR—and the different class of HED meteorites shows that average spectrum of Vesta resembles howardite spectra. Nevertheless, the Vesta spectra at high spatial resolution reveal variations in the distribution of HED‐like mineralogies on the asteroid. The data have been used to derive HED distribution on Vesta, reported in Ammannito et al. (2013), and to compute the average Vestan spectra of the different HED lithologies, reported here. The spectra indicate that, not only are all the different HED lithologies present on Vesta, but also carbonaceous chondritic material, which constitutes the most abundant inclusion type found in howardites, is widespread. However, the hydration feature used to identify carbonaceous chondrite material varies significantly on Vesta, revealing different band shapes. The characteristic of these hydration features cannot be explained solely by infalling of carbonaceous chondrite meteorites and other possible origins must be considered. The relative proportion of HEDs on Vesta's surface is computed, and results show that most of the vestan surface is compatible with eucrite‐rich howardites and/or cumulate or polymict eucrites. A very small percentage of surface is covered by diogenite, and basaltic eucrite terrains are relatively few compared with the abundance of basaltic eucrites in the HED suite. The largest abundance of diogenitic material is found in the Rheasilvia region, a deep basin, where it clearly occurs below a basaltic upper crust. However, diogenite is also found elsewhere; although the depth to diogenite is consistent with one magma ocean model, its lateral extent is not well constrained.  相似文献   

A reappraisal of seismic Q evaluated in Campi Flegrei caldera. Receipt for the application to risk analysis     

Edoardo Del Pezzo  Francesca Bianco 《Journal of Seismology》2013,17(2):829-837

The civil defense of Italy and the European community have planned to reformulate the volcanic risk in several volcanic areas of Italy, among which Mt. Vesuvius and Campi Flegrei, by taking into account the possible occurrence of damaging pre- or syn-eruptive seismic events. Necessary to achieve this goal is the detailed knowledge of the local attenuation–distance relations. In the present note, we make a survey of the estimates of seismic quality factor (the inverse is proportional to the attenuation coefficient with distance) reported in literature for the area of Campi Flegrei where many, but sometimes contradictory results have been published on this topic. We try to review these results in order to give indications for their correct use when calculating the attenuation laws for this area.  相似文献   

Annual runoff assessment in arid and semiarid Mediterranean watersheds under the Budyko's framework          下载免费PDF全文

F. Viola  D. Caracciolo  A. Forestieri  D. Pumo  L.V. Noto 《水文研究》2017,31(10):1876-1888

The solution of many practical water problems is strictly connected to the availability of reliable and widespread information about runoff. The estimation of mean annual runoff and its interannual variability for any basin over a wide region, even if ungauged, would be fundamental for both water resources assessment and planning and for water quality analysis. Starting from these premises, the main aim of this work is to show a new approach, based on the Budyko's framework, for mapping the mean annual surface runoff and deriving the probability distribution of the annual runoff in arid and semiarid watersheds. As a case study, the entire island of Sicily, Italy, is here proposed. First, time series data of annual rainfall, runoff, and reconstructed series of potential evapotranspiration have been combined within the Budyko's curve framework to obtain regional rules for rainfall partitioning between evapotranspiration and runoff. Then this knowledge has been used to infer long‐term annual runoff at the point scale by means of interpolated rainfall and potential evapotranspiration. The long‐term annual runoff raster layer has been obtained at each pixel of the drainage network, averaging the upstream runoff using advanced spatial analysis techniques within a GIS environment. Furthermore, 2 alternative methods are here proposed to derive the distribution of annual runoff, under the assumption of negligible interannual variations of basin water storage. The first method uses Monte Carlo simulations, combining rainfall and potential evapotranspiration randomly extracted from independent distributions. The second method is based on a simplification of the Budyko's curve and analytically provides the annual runoff distribution as the derived distribution of annual rainfall and potential evapotranspiration. Results are very encouraging: long‐term annual runoff and its distribution have been derived and compared with historical records at several gauged stations, obtaining satisfactory matching.  相似文献   

Improving flow forecasting by error correction modelling in altered catchment conditions          下载免费PDF全文

Francesca Pianosi  Andrea Castelletti  Leonardo Mancusi  Elisabetta Garofalo 《水文研究》2014,28(4):2524-2534

Despite human is an increasingly significant component of the hydrologic cycle in many river basins, most hydrologic models are still developed to accurately reproduce the natural processes and ignore the effect of human activities on the watershed response. This results in non‐stationary model forecast errors and poor predicting performance every time these models are used in non‐pristine watersheds. In the last decade, the representation of human activities in hydrological models has been extensively studied. However, mathematical models integrating the human and the natural dimension are not very common in hydrological applications and nearly unknown in the day‐to‐day practice. In this paper, we propose a new simple data‐driven flow forecast correction method that can be used to simultaneously tackle forecast errors from structural, parameter and input uncertainty, and errors that arise from neglecting human‐induced alterations in conceptual rainfall–runoff models. The correction system is composed of two layers: (i) a classification system that, based on the current flow condition, detects whether the source of error is natural or human induced and (ii) a set of error correction models that are alternatively activated, each tailored to the specific source of errors. As a case study, we consider the highly anthropized Aniene river basin in Italy, where a flow forecasting system is being established to support the operation of a hydropower dam. Results show that, even by using very basic methods, namely if‐then classification rules and linear correction models, the proposed methodology considerably improves the forecasting capability of the original hydrological model. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Flooding scenarios due to land subsidence and sea‐level rise: a case study for Lipari Island (Italy)          下载免费PDF全文

Marco Anzidei  Alessandro Bosman  Roberto Carluccio  Daniele Casalbore  Francesca D'Ajello Caracciolo  Alessandra Esposito  Iacopo Nicolosi  Grazia Pietrantonio  Antonio Vecchio  Cosmo Carmisciano  Massimo Chiappini  Francesco Latino Chiocci  Filippo Muccini  Vincenzo Sepe 《地学学报》2017,29(1):44-51

Archaeological and instrumental data indicate that the southern sector of the volcanic island of Lipari has been subsiding for the last 2100 years due to isostatic and tectonic factors, at variable rates of up to ~11 mm a^?1. Based on this data, a detailed marine flooding scenario for 2100 AD is provided for the bay of Marina Lunga in the eastern part of the island from (1) an ultra‐high‐resolution Digital Terrain and Marine Model (DTMM) generated from multibeam bathymetry (MB) and Unmanned Aerial Vehicles (UAV), (2) the rate of land subsidence from Global Positioning System (GPS) data and (3) the regional sea‐level projections of the International Panel on Climate Change (IPCC). When land subsidence is considered, the upper bound of sea‐level rise is estimated at 1.36 m and 1.60 m for RCP4.5 and RCP8.5 climate change scenarios, respectively. Here, we show the expected impact of marine flooding at Lipari for the next 85 years and discuss the hazard implications for the population living along the shore.  相似文献   

Seismic soil–structure interaction in multi‐span bridges: Application to a railway bridge     

Sandro Carbonari  Francesca Dezi  Graziano Leoni 《地震工程与结构动力学》2011,40(11):1219-1239

The effects of soil‐structure interaction on the seismic response of multi‐span bridges are investigated by means of a modelling strategy based on the domain decomposition technique. First, the analysis methodology is presented: kinematic interaction analysis is performed in the frequency domain by means of a procedure accounting for radiation damping, soil–pile and pile‐to‐pile interaction; the seismic response of the superstructure is evaluated in the time domain by means of user‐friendly finite element programs introducing suitable lumped parameter models take into account the frequency‐dependent impedances of the soil–foundation system. Second, a real multi‐span railway bridge longitudinally restrained at one abutment is analyzed. The input motion is represented by two sets of real accelerograms: one consistent with the Italian seismic code and the other constituted by five records characterized by different frequency contents. The seismic response of the compliant‐base model is compared with that obtained from a fixed‐base model. Pile stress resultants due to kinematic and inertial interactions are also evaluated. The application demonstrates the importance of performing a comprehensive analysis of the soil–foundation–structure system in the design process, in order to capture the effects of soil‐structure interaction in each structural element that may be beneficial or detrimental. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

Linear soil–structure interaction of coupled wall–frame structures on pile foundations     

Sandro Carbonari  Francesca Dezi  Graziano Leoni 《Soil Dynamics and Earthquake Engineering》2011

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Formation of cordierite-bearing lavas during anatexis in the lower crust beneath Lipari Island (Aeolian arc,Italy)   总被引：2，自引：1，他引：1  

Corrado Di Martino  Francesca Forni  Maria Luce Frezzotti  Rosaria Palmeri  James D. Webster  Robert A. Ayuso  Federico Lucchi  Claudio A. Tranne 《Contributions to Mineralogy and Petrology》2011,162(5):1011-1030

Cordierite-bearing lavas (CBL;~105 ka) erupted from the Mt. S. Angelo volcano at Lipari (Aeolian arc, Italy) are high-K andesites, displaying a range in the geochemical and isotopic compositions that reflect heterogeneity in the source and/or processes. CBL consist of megacrysts of Ca-plagioclase and clinopyroxene, euhedral crystals of cordierite and garnet, microphenocrysts of orthopyroxene and plagioclase, set in a heterogeneous rhyodacitic-rhyolitic groundmass containing abundant metamorphic and gabbroic xenoliths. New petrographic, chemical and isotopic data indicate formation of CBL by mixing of basaltic-andesitic magmas and high-K peraluminous rhyolitic magmas of anatectic origin and characterize partial melting processes in the lower continental crust of Lipari. Crustal anatectic melts generated through two main dehydration-melting peritectic reactions of metasedimentary rocks: (1) Biotite + Aluminosilicate + Quartz + Albite = Garnet + Cordierite + K-feldspar + Melt; (2) Biotite + Garnet + Quartz = Orthopyroxene + Cordierite + K-feldspar + Melt. Their position into the petrogenetic grid suggests that heating and consequent melting of metasedimentary rocks occurred at temperatures of 725 < T < 900°C and pressures of 0.4–0.45 GPa. Anatexis in the lower crust of Lipari was induced by protracted emplacement of basic magmas in the lower crust (~130 Ky). Crustal melting of the lower crust at 105 ka affected the volcano evolution, impeding frequent mafic-magma eruptions, and promoting magma stagnation and fractional crystallization processes.  相似文献