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1.
Multiplatform observation of the surface circulation in the Gulf of Naples (Southern Tyrrhenian Sea) 总被引:1,自引:1,他引:0
Marco Uttieri Daniela Cianelli Bruno Buongiorno Nardelli Berardino Buonocore Pierpaolo Falco Simone Colella Enrico Zambianchi 《Ocean Dynamics》2011,61(6):779-796
The Gulf of Naples (Southern Tyrrhenian Sea) is a highly urbanised area, where human activities and natural factors (e.g.
river runoff, exchanges with adjacent basins) can strongly affect the water quality. In this work we show how surface transport
can influence the distribution of passively drifting surface matter, and more in general if and how the circulation in the
basin can promote the renovation of the surface layer. To this aim, we carried out a multiplatform analysis by putting together
HF radar current fields, satellite images and modelling tools. Surface current fields and satellite images of turbidity patterns
were used to initialise and run model simulations of particle transport and diffusion. Model results were then examined in
relation to the corresponding satellite distributions. This integrated approach permits to investigate the concurrent effects
of surface dynamics and wind forcing in determining the distribution of passive tracers over the basin of interest, identifying
key mechanisms supporting or preventing the renewal of surface waters as well as possible areas of aggregation and retention. 相似文献
2.
Franco Ricci Lucchi Albina Colella Gianni Gabbianelli Sergio Rossi William R. Normark 《Geo-Marine Letters》1984,3(2-4):71-77
The Crati Fan is located in the tectonically active submerged extension of the Apennines chain and foretrough. The small fan
system is growing in a relatively shallow (200 to 450 m), elongate nearshore basin receiving abundant input from the Crati
River. The fan is characterized by a short, steep, channelized section (inner or upper fan) and a smooth, slightly bulging
distal section (outer or lower fan). The numerous subparallel channels head in the shelf or littoral zone and do not form
branching distributary patterns. Sand and mud depositional lobes of the outer fan stretch over more than 60% of fan length.
Margin setting represents fan and/or source area 相似文献
3.
Kristy F. Tiampo David D. Bowman Harmony Colella John B. Rundle 《Pure and Applied Geophysics》2008,165(3-4):693-709
In this work, we provide a joint study of the stress accumulation method (SAM) (King and Bowman, 2003) and the Pattern Informatics (PI) index (Tiampo et al., 2002b). We examine the theoretical underpinnings for the similarities between the two techniques, as well as the differences in their application. The SAM technique is employed to determine likely mechanisms for smaller areas of increased probability identified by the PI index, while a modified version of the PI index can be used to locate regions where the smaller magnitude associated with the anomaly is below the resolution of the SAM. Finally, we present three case studies from different regions of the San Andreas fault system to illustrate both their complementary nature, as well as the advantages to combining them in one synthesized analysis. 相似文献
4.
M. Colella G. R. Lumpkin Z. Zhang E. C. Buck K. L. Smith 《Physics and Chemistry of Minerals》2005,32(1):52-64
In this study, the valence states of uranium in synthetic and natural brannerite samples were studied using a combination of transmission electron microscopy-electron energy loss spectroscopy, scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), and X-ray photoelectron spectroscopy (XPS) techniques. We used a set of five (UO2, CaUO4, SrCa2UO6, UTi2O6, and Y0.5U0.5Ti2O6) U standard samples, including two synthetic brannerites, to calibrate the EELS branching ratio, M5/(M4 +M5), against the number of f electrons. The EELS data were collected at liquid nitrogen temperature in order to minimise the effects of electron beam reduction of U6+ and U5+. Test samples consisted of three additional synthetic brannerites (Th0.7U0.3Ti2O6, Ca0.2U0.8Ti2O6, and Th0.55U0.3Ca0.15Ti2O6) and three natural brannerites from different localities. The natural brannerite samples are all completely amorphous, due to cumulative alpha decay events over geological time periods (24–508 Ma). Our U valence calibration results are in reasonable agreement with previous work, suggesting possibly a non-linear relationship between the branching ratio and the number of f electrons (and hence the average valence state) of U in solids. We found excellent agreement between the nominal valence states of U and the average valence states determined directly by EELS and estimated by EDX analysis (with assumptions regarding stoichiometry) in two of the three synthetic brannerite test samples. The average U oxidation states of the five synthetic brannerite samples, as derived from XPS analyses, are also in good agreement with those determined by other techniques. The average valence states of U in three amorphous (metamict) natural brannerite samples with alpha decay doses ranging from 3.6×1016 to 6.9×1017 /mg were found to be 4.4, 4.7, and 4.8, consistent with the presence of U5+ and/or U6+ as well as U4+ in these samples. These results are in general agreement with previous wet chemical analyses of natural brannerite. However, the average valence states inferred by SEM-EDX for two of the natural brannerite samples do not show satisfactory agreement with the EELS determined valence. This may be due to the occurrence of OH– groups, cation vacancies, anion vacancies, or excess oxygen in the radiation-damaged structure of natural brannerite. 相似文献
5.
6.
Hindcast of oil-spill pollution during the Lebanon crisis in the Eastern Mediterranean, July-August 2006 总被引:2,自引:0,他引:2
Coppini G De Dominicis M Zodiatis G Lardner R Pinardi N Santoleri R Colella S Bignami F Hayes DR Soloviev D Georgiou G Kallos G 《Marine pollution bulletin》2011,62(1):140-153
MOON (Mediterranean Operational Oceanography Network http://www.moon-oceanforecasting.eu) provides near-real-time information on oil-spill detection (ocean color and SAR) and predictions [ocean forecasts (MFS and CYCOFOS) and oil-spill predictions (MEDSLIK)]. We employ this system to study the Lebanese oil-pollution crisis in summer 2006 and thus to assist regional and local decision makers in Europe, regionally and locally. The MEDSLIK oil-spill predictions obtained using CYCOFOS high-resolution ocean fields are compared with those obtained using lower-resolution MFS hydrodynamics, and both are validated against satellite observations. The predicted beached oil distributions along the Lebanese and Syrian coasts are compared with in situ observations.The oil-spill predictions are able to simulate the northward movement of the oil spill, with the CYCOFOS predictions being in better agreement with satellite observations. Among the free MEDSLIK parameters tested in the sensitivity experiments, the drift factor appears to be the most relevant to improve the quality of the results. 相似文献
7.
M. Boni N. Mondillo G. Balassone M. Joachimski A. Colella 《International Journal of Earth Sciences》2013,102(1):61-71
One of the main effects of supergene alteration of ore-bearing hydrothermal dolomite in areas surrounding secondary zinc orebodies (Calamine-type nonsulfides) in southwestern Sardinia (Italy) is the formation of a broad halo of Zn dolomite. The characteristics of supergene Zn dolomite have been investigated using scanning electron microscopy and qualitative energy-dispersive X-ray spectroscopy, thermodifferential analysis, and stable isotope geochemistry. The supergene Zn dolomite is characterized by variable amounts of Zn, and low contents of Pb and Cd in the crystal lattice. It is generally depleted in Fe and Mn relative to precursor hydrothermal dolomite (Dolomia Geodica), which occurs in two phases (stoichiometric dolomite followed by Fe-Mn-Zn-rich dolomite), well distinct in geochemistry. Mg-rich smithsonite is commonly associated to Zn dolomite. Characterization of Zn-bearing dolomite using differential thermal analysis shows a drop in temperature of the first endothermic reaction of dolomite decomposition with increasing Zn contents in dolomite. The supergene Zn dolomites have higher δ18O but lower δ13C values than hydrothermal dolomite. In comparison with smithsonite-hydrozincite, the supergene Zn dolomites have higher δ18O, but comparable δ13C values. Formation of Zn dolomite from meteoric waters is indicated by low δ13C values, suggesting the influence of soil-gas CO2 in near-surface environments. The replacement of the dolomite host by supergene Zn dolomite is interpreted as part of a multistep process, starting with a progressive “zincitization” of the dolomite crystals, followed by a patchy dedolomitization s.s. and potentially concluded by the complete replacement of dolomite by smithsonite. 相似文献
8.
9.
Alessio Langella Domenico Calcaterra Piergiulio Cappelletti Abner Colella Maria Pia D’Albora Vincenzo Morra Maurizio de Gennaro 《Environmental Earth Sciences》2009,59(1):145-160
Results of a research carried out on the lavas from Campi Flegrei and Somma-Vesuvius volcanic districts are reported here.
The lavas have been widely employed, since Roman age, in several important monumental buildings of the Campania region, mainly
in the town of Naples and in its province. They are classified as trachytes (Campi Flegrei products), tephri-phonolites and
phono-tephrites (Somma-Vesuvius complex) from a petrographical point of view. Sampling was carried out from well-known exploitation
districts. A substantial chemical difference between the products of the two sectors was confirmed, while petrophysical characterization
evidenced similarity among the two different materials, although some differences were recorded even in samples coming from
the same exploitation site. 相似文献
10.
Elena Colella Emiliano Ortore Christian Circi Ennio Condoleo 《Earth, Moon, and Planets》2017,120(1):31-39
This paper aims at investigating the feasibility of gaining complete and continuous coverage of an extended equatorial belt of Mars, under the effects of orbital perturbations. The problem could be solved by considering a minimum number of three probes, which move slightly off the Martian Areostationary Orbit. The proposed configurations allow the achievement of the goal without entailing corrective manoeuvres and presenting only a longitudinal motion with respect to the surface of Mars. 相似文献