A microtremor survey to define the subsoil structure in a mud volcanoes area: the case study of Salinelle (Mt. Etna,Italy)     

Francesco Panzera  Simona Sicali  Giuseppe Lombardo  Sebastiano Imposa  Stefano Gresta  Sebastiano D’Amico 《Environmental Earth Sciences》2016,75(15):1140

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Petrology of parasitic and eccentric cones on the flanks and base of Somma-Vesuvius     

Ray Macdonald  Bogusław Bagiński  Giuseppe Rolandi  Benedetto De Vivo  Anna Kopczyńska 《Mineralogy and Petrology》2016,110(1):65-85

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Horizontal accuracy assessment of very high resolution Google Earth images in the city of Rome,Italy     

Giuseppe Pulighe  Valerio Baiocchi  Flavio Lupia 《International Journal of Digital Earth》2016,9(4):342-362

Google Earth (GE) has recently become the focus of increasing interest and popularity among available online virtual globes used in scientific research projects, due to the free and easily accessed satellite imagery provided with global coverage. Nevertheless, the uses of this service raises several research questions on the quality and uncertainty of spatial data (e.g. positional accuracy, precision, consistency), with implications for potential uses like data collection and validation. This paper aims to analyze the horizontal accuracy of very high resolution (VHR) GE images in the city of Rome (Italy) for the years 2007, 2011, and 2013. The evaluation was conducted by using both Global Positioning System ground truth data and cadastral photogrammetric vertex as independent check points. The validation process includes the comparison of histograms, graph plots, tests of normality, azimuthal direction errors, and the calculation of standard statistical parameters. The results show that GE VHR imageries of Rome have an overall positional accuracy close to 1 m, sufficient for deriving ground truth samples, measurements, and large-scale planimetric maps.  相似文献   

Procedimento rapido per il calcolo del coefficiente di correlazione lineare     

Prof. Dr. Giuseppe Lovera 《Pure and Applied Geophysics》1953,24(1):1-4

Riassunto Nell'ipotesi di una correlazione normale tra due variabili, si deduce una formula che consente il calcolo del coefficiente di correlazione lineare dal semplice conteggio delle concordanze di segno delle coppie di valori corrispondenti da correlare, riferiti alle rispettive medie aritmetiche. La relazione tra la frequenza delle concordanze di segno ed il coefficiente di correlazione è pure tabulata, per accrescere ulteriormente la speditezza delle operazioni.

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Summary For the case of a normal correlation between two variables, a formula is deduced, that enables the calculation of the coefficient of linear correlation simply starting from the number of the sign concomitances in the pairs of correspondent values of the two variables, related to their aritmetical means. The formula is tabulated also, in the aim of increasing the speed of calculation.

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Monitoring of a methane-seeping pockmark by cabled benthic observatory (Patras Gulf, Greece)     

Giuditta Marinaro  Giuseppe Etiope  Nadia Lo Bue  Paolo Favali  George Papatheodorou  Dimitris Christodoulou  Flavio Furlan  Francesco Gasparoni  George Ferentinos  Michel Masson  Jean-François Rolin 《Geo-Marine Letters》2006,26(5):297-302

A new seafloor observatory, the gas monitoring module (GMM), has been developed for continuous and long-term measurements of methane and hydrogen sulphide concentrations in seawater, integrated with temperature (T), pressure (P) and conductivity data at the seafloor. GMM was deployed in April 2004 within an active gas-bearing pockmark in the Gulf of Patras (Greece), at a water depth of 42 m. Through a submarine cable linked to an onshore station, it was possible to remotely check, via direct phone connection, GMM functioning and to receive data in near-real time. Recordings were carried out in two consecutive campaigns over the periods April–July 2004, and September 2004–January 2005, amounting to a combined dataset of ca. 6.5 months. This represents the first long-term monitoring ever done on gas leakage from pockmarks by means of CH₄+H₂S+T+P sensors. The results show frequent T and P drops associated with gas peaks, more than 60 events in 6.5 months, likely due to intermittent, pulsation-like seepage. Decreases in temperature in the order of 0.1–1°C (up to 1.7°C) below an ambient T of ca. 17°C (annual average) were associated with short-lived pulses (10–60 min) of increased CH₄+H₂S concentrations. This seepage “pulsation” can either be an active process driven by pressure build-up in the pockmark sediments, or a passive fluid release due to hydrostatic pressure drops induced by bottom currents cascading into the pockmark depression. Redundancy and comparison of data from different sensors were fundamental to interpret subtle proxy signals of temperature and pressure which would not be understood using only one sensor.  相似文献   

Stone mobility and longshore transport at reshaping breakwaters     

Alberto Lamberti  Giuseppe R. Tomasicchio   《Coastal Engineering》1997,29(3-4)

Physical model tests have been performed in two different wave flumes to analyse the threshold of stone movement and quantify the frequency and length of displacements due to head-on wave attacks at a reshaping breakwater. Data on stone movements were obtained from the observation of cumulative displacements at the end of each wave attack and from video records during the attack. Threshold conditions, frequency of movement and displacement length are expressed as function of a suitably modified stability number.A simple model is defined relating longshore transport due to oblique wave attack to stone mobility. The transport model is based on the assumption that movement statistics is affected by obliquity only through the appropriate mobility index and that stones move during up- and down-rush in the direction of incident and reflected waves. Without any calibration, results compare favourably with experimental data available in literature in the range of low mobility conditions where movement statistics was observed. A calibration is provided in order to obtain an accurate transport formula valid in a wide mobility range i.e. for reshaping breakwaters and up to gravel beaches.  相似文献   

An experiment at sea on the reflection of the wind waves     

P. Boccotti  G. Barbaro  V. Fiamma  L. Mannino  A. Rotta 《Ocean Engineering》1993,20(5)

Before a reflecting wall, the wind waves strongly differ from the periodic waves. The nodes and the antinodes tend to disappear starting one wave length from the wall. The wave period, as a function of the distance from the wall, exhibits some negative discontinuities at the nodes. Those properties were predicted from an analysis of theoretical spectra and were confirmed by an experiment which employed 30 wave gauges at sea. The experiment revealed also a characteristic pressure-fall under the crests of the highest waves at the wall. The phenomenon was related to high water jets detected at the centers of the wave fronts.  相似文献   

Ecological Differences in the Distribution of two Tethya (Porifera, Demospongiae) Species Coexisting in a Mediterranean Coastal Lagoon     

Giuseppe Corriero  rea Balduzz  Michele Sarà 《Marine Ecology》1989,10(4):303-315

Abstract. In the Sicilian lagoon Stagnone di Marsala, Tethya aurantium and T. citrina show different ecological distributions, although some overlapping occurs. The first species reaches its highest density where linear currents are maximal, and in this habitat it is particularly frequent on Posidonia oceanica rhizomes. The second species is more abundant in still water locations and is equally common on Posidonia rhizomes and on calcareous concretions. Such distributions can be related to water movement, Posidonia shoot density, and associated factors such as sedimentation and food availability. These observations are consistent with an adaptive interpretation of the morphofunctional features distinguishing the two species.  相似文献   

3D displacement maps of the 2009 L’Aquila earthquake (Italy) by applying the SISTEM method to GPS and DInSAR data     

Francesco Guglielmino  Marco Anzidei  Pierre Briole  Panagiotis Elias  Giuseppe Puglisi 《地学学报》2013,25(1):79-85

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Erratum to: Melilite-type and melilite-related compounds: structural variations along the join Sr2?x Ba x MgSi2O7 (0?≤?x?≤?2) and high-pressure behavior of the two end-members     

Matteo Ardit  Michele Dondi  Marco Merlini  Giuseppe Cruciani 《Physics and Chemistry of Minerals》2012,39(7):599-599

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