The M_w 5.4 Reggio Emilia 1996 earthquake: active compressional tectonics in the Po Plain, Italy     

G. Selvaggi  F. Ferulano  M. Di Bona  A. Frepoli  R. Azzara  A. Basili  C. Chiarabba  M. G. Ciaccio  F. Di Luccio  F. P. Lucente  L. Margheriti   C. Nostro 《Geophysical Journal International》2001,144(1):1-13

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Sr,Nd,Pb and trace element systematics of the New Caledonia harzburgites:Tracking source depletion and contamination processes in a SSZ setting     

Arianna Secchiari  Alessandra Montanini  Delphine Bosch  Patrizia Macera  Dominique Cluzel 《地学前缘(英文版)》2020,11(1):37-55

The New Caledonia ophiolite(Peridotite Nappe)consists primarily of harzburgites,locally overlain by mafic-ultramafic cumulates,and minor spinel and plagioclase lherzolites.In this study,a comprehensive geochemical data set(major and trace element,Sr-Nd-Pb isotopes)has been obtained on a new set of fresh harzburgites in order to track the processes recorded by this mantle section and its evolution.The studied harzburgites are low-strain tectonites showing porphyroclastic textures,locally grading into protomylonitic textures.They exhibit a refractory nature,as attested by the notable absence of primary clinopyroxene,very high Fo content of olivine(91-93 mol.%),high Mg#of orthopyroxene(0.91-0.93)and high Cr#of spinel(0.44-0.71).The harzburgites are characterised by remarkably low REE concentrations(<0.1 chondritic values)and display"U-shaped"profiles,with steeply sloping HREE(DyN/YbN=0.07-0.16)and fractionated LREE-MREE segments(LaN/SmN=2.1-8.3),in the range of modern fore-arc peridotites.Geochemical modelling shows that the HREE composition of the harzburgites can be reproduced by multi-stage melting including a first phase of melt depletion in dry conditions(15%fractional melting),followed by hydrous melting in a subduction zone setting(up to 15%-18%).However,melting models fail to explain the enrichments observed for some FME(i.e.Ba,Sr,Pb),LREE-MREE and Zr-Hf.These enrichments,coupled with the frequent occurrence of thin,undeformed films of Al2 O3,and CaO-poor orthopyroxene(Al2O3=0.88-1.53 wt.%,CaO=0.31-0.56 wt.%)and clinopyroxene with low Na2 O(0.03-0.16 wt.%),Al2 O3(0.66-1.35 wt.%)and TiO2(0.04-0.10 wt.%)contents,point to FME addition during fluid-assisted melting followed by late stage metasomatism most likely operated by subductionrelated melts with a depleted trace element signature.Nd isotopic ratios range from unradiogenic to radiogenic(-0.80<εNdi≤+13.32)and negatively correlate with Sr isotopes(0.70257≤87Sr/86Sr≤0.70770).Pb isotopes cover a wide range,trending from DMM toward enriched,sediment-like,compositions.We interpret the geochemical signature displayed by the New Caledonia harzburgites as reflecting the evolution of a highly depleted fore-arc mantle wedge variably modified by different fluid and melt inputs during Eocene subduction.  相似文献   

A habitat-specific fish-based approach to assess the ecological status of Mediterranean coastal lagoons   总被引：1，自引：0，他引：1  

Anita Franco  Patrizia Torricelli  Piero Franzoi 《Marine pollution bulletin》2009,58(11):1704-1717

A habitat approach was promoted in the framework of ecological status assessment of transitional waters, assuming the importance of habitat heterogeneity to the overall system status. The approach was applied to the use of fish-based multimetric indices by adapting them to seagrass and marsh habitats in the Venice lagoon, Italy, through selection of appropriate metrics and reference conditions. While for marsh habitats, no clear patterns resulted, the index response for seagrass was consistent with the habitat degradation and loss recorded in the lagoon between 2002 and 2005 and with the higher habitat disturbance in southern and central lagoon sub-basins. The assessment of individual habitats is presented as a first step in the process of evaluating the overall condition of a Mediterranean lagoon environment, which should also take account of the diversity of habitats and their availability within the system to properly define an overall index of ecological status.  相似文献   

Recycling and “re-hydration” of degassed magma inducing transient dissolution/crystallization events at Stromboli (Italy)     

Patrizia Landi  Nicole Mtrich  Antonella Bertagnini  Mauro Rosi 《Journal of Volcanology and Geothermal Research》2008,174(4):325-336

Intrusive degassing and recycling of degassed and dense magma at depth have been proposed for a long time at Stromboli. The brief explosive event that occurred at the summit craters on 9 January 2005 threw out bombs and lapilli that could be good candidates to illustrate recycling of shallow degassed magma at depth. We present an extensive data set on both the textures and the mineral, bulk rock and glassy matrix chemistry of the “9 Jan” products. The latter have the common shoshonitic–basaltic bulk composition of lavas and scoriae issued from typical strombolian activity. In contrast they differ by the heterogeneous chemistry of their matrix glasses and their crystal textures that testify to crystal dissolution event(s) just prior magma crystallization upon ascent and eruption. Comparison between mineral paragenesis of the natural products and experimental phase equilibria suggest water-induced magma re-equilibration. We propose that mineral dissolution is related to water enrichment of the recycled degassed magma, via differential gas bubble transfer and to some extents its physical mixing with volatile-rich magma blobs. However, all these features illustrate transient processes. Even though evidence of mineral dissolution is ubiquitous at Stromboli, its effect on the bulk magma chemistry is minor because of the subtle interplay between mineral dissolution and crystallization in magmas having comparable bulk chemistry.  相似文献   

Ultrasound assisted extraction and determination of the carbohydrate fraction in marine sediments     

Mauro Mecozzi  Patrizia Dragone  Marina Amici  Eva Pietrantonio 《Organic Geochemistry》2000,31(12)

In this paper, an ultrasound–acetic acid procedure for the simultaneous extraction and hydrolysis of carbohydrates in marine sediments prior to their colorimetric determination is described. The main advantage of the proposed procedure is the improved analytical accuracy achieved. Extraction and hydrolysis are quantitative since the oxidative reactions which cause the underestimation of the total carbohydrate amount are minimized. Moreover the procedure is fast, requiring only 5 h for the whole analysis (extraction, hydrolysis and colorimetric determination by the phenol-sulphuric acid method). The proposed procedure has recoveries generally higher than 80% and gives comparable results with the conventional 24 h HCl extraction.  相似文献   

Integrated Geophysical Investigations at the Greek Kamarina Site (Southern Sicily,Italy)     

Salvatore Scudero  Raffaele Martorana  Patrizia Capizzi  Antonino Pisciotta  Antonino D’Alessandro  Carla Bottari  Giovanni Di Stefano 《Surveys in Geophysics》2018,39(6):1181-1200

Kamarina, located in southern Sicily (Italy), was an important Greek colony since its foundation in the sixth century BC. Archaeological excavations, carried out since the twentieth century, uncovered only limited portions of the site so far. Despite the importance of the Greek colony, the presence of remarkable buildings that archaeologists expected to bring to light has not found fully correspondence in the archaeological excavations. Consequently, the integrated geophysical prospection carried out in the study area is aimed to support and address the future archaeological investigations. After the photographic and thermographic survey obtained by an unmanned aerial vehicle, we performed a systematic survey through ground magnetic and GPR methods over an area of 6200 m². The acquisition procedures have been optimized in order to get the best results combining high resolution and elevated speed of acquisition. The results derived from the three geophysical techniques have been conveniently combined by means of a cluster analysis, allowing us to clearly identify a series of buried archaeological features. Because of their geometrical characteristics, often in good agreement with the spatial arrangement of the archaeological remains at the surface, these buried archaeological features can be interpreted as roads, walls, or buildings foundations in which the various construction phases of the city can be clearly recognized. The integrated approach has proven to be essential for a robust interpretation of the archaeogeophysical investigation.  相似文献   

BaMn[CO3]2 – a previously unrecognized double carbonate in low-temperature environments: Structural,spectroscopic, and textural tools for future identification     

Michael E. Böttcher  Herta S. Effenberger  Peer-Lennart Gehlken  Georg H. Grathoff  Burkhard C. Schmidt  Patrizia Geprägs  Rainer Bahlo  Olaf Dellwig  Thomas Leipe  Vera Winde  André Deutschmann  Alexander Stark  David Gallego-Torres  Francisca Martinez-Ruiz 《Chemie der Erde / Geochemistry》2012,72(1):85-89

Following a tentative evidence for the occurrence of low-temperature barium manganese(II) carbonates in brackish sediments of the Baltic Sea, a stoichiometric double carbonate, BaMn[CO₃]₂, was synthesized from aqueous solutions at ambient temperature for the first time. Here we report the results of a multi-method approach, including scanning electron microscopy (SEM–EDX) investigations, the chemical composition, and, in particular, the diagnostic powder X-ray diffraction pattern, as well as diagnostic parts of the FT infrared absorption and Raman spectra for future identification of this new carbonate in low-temperature environments, like brackish sediments.  相似文献   

Ecology of active rock glaciers and surrounding landforms: climate,soil, plants and arthropods     

Duccio Tampucci  Mauro Gobbi  Giuseppe Marano  Patrizia Boracchi  Giacomo Boffa  Francesco Ballarin  Paolo Pantini  Roberto Seppi  Chiara Compostella  Marco Caccianiga 《Boreas: An International Journal of Quaternary Research》2017,46(2):185-198

Active rock glaciers are periglacial landforms consisting of coarse debris with interstitial ice or ice‐core. Recent studies showed that such landforms are able to support plant and arthropod life and could act as warm‐stage refugia for cold‐adapted species due to their microclimate features and thermal inertia. However, integrated research comparing active rock glaciers with surrounding landforms to outline their ecological peculiarities is still scarce. We analysed the abiotic (ground surface temperature and humidity, soil physical and chemical parameters) and biotic (plant and arthropod communities) features of two Alpine active rock glaciers with contrasting lithology (silicate and carbonate), and compared them with the surrounding iceless landforms as reference sites (stable slopes and active scree slopes). Our data show remarkable differences between stable slopes and unstable landforms as a whole, while few differences occur between active scree slopes and active rock glaciers: such landforms show similar soil features but different ground surface temperatures (lower on active rock glaciers) and different occurrence of cold‐adapted species (more frequent/abundant on active rock glaciers). Both plant and arthropod species distributions depend mainly on the geographical context as a function of soil pH and on the contrast between stable slopes and unstable landforms as a function of the coarse debris fraction and organic matter content, while the few differences between active scree slopes and active rock glaciers can probably be attributed to microclimate. The role of active rock glaciers as potential warm‐stage refugia for cold‐adapted species is supported by our data; however, at least in the European Alps, their role in this may be less important than that of debris‐covered glaciers, which are able to host cold‐adapted species even below the climatic tree line.  相似文献   

A modelling approach to assessing variations of total suspended solids (tss) mass fluxes during storm events          下载免费PDF全文

Patrizia Piro  Marco Carbone 《水文研究》2014,28(4):2419-2426

Connections between the catchment hydrology and accumulation, washoff and transport of pollutants in wet weather greatly affect the management of urban drainage and its wet‐weather effluents. In recent years, the concept of the first flush has gained on prominence and was further developed for analyzing the interaction between the hydrology and transport of runoff pollutants. One of the most important definitions of the first flush can be derived from the analysis of the m(v) curves (i.e. the curves in which the normalized cumulative pollutant mass is plotted vs the normalized cumulative runoff volume). Indeed the m(v) curves, indicating the distribution of pollutant mass versus volume in wet‐weather flow (WWF) discharges, are commonly used for comparing pollutant discharges for different rainfall events and catchments. In this study, the m(v) curves were used to define the concepts of flow‐limited and mass‐limited WWF events. These two different behaviours have been analysed for rainfall/runoff events observed in the urbanized part of the Liguori catchment in Cosenza (Italy). In order to advance the understanding of the intra‐event variability of m(v) curves, the mathematical rainfall/runoff model Storm Water Management Model of the US Environmental Protection Agency (SWMM) was calibrated for eight observed rainfall/runoff events and the differences between observed and simulated m(v) curves were analysed. The results showed a good correlation between the observed and simulated m(v) curves, and this finding offers further benefits in SWMM model calibration. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Vertical crustal motions from differential tide gauge observations and satellite altimetry in southern Italy     

Carla Braitenberg  Patrizia MarianiLavinia Tunini  Barbara GrilloIldikò Nagy 《Journal of Geodynamics》2011

Our goal is to determine vertical crustal movement rates from tide gauge and satellite altimetry measurements. Tide gauges measure sea level, but as they are fixed to the crust, they sense both sea surface height variations and vertical crustal movements. The differential sea level rates of sufficiently nearby stations are a good means to determine differential crustal movement rates, when sea level height variations can be assumed to be homogeneous. Satellite altimetric measurements determine sea surface height variations directly and can be used to separate the crustal signal from the sea surface height variations in tide gauge measurements. The correction of the tide gauge sea level rates for the sea surface height contribution requires collocation of the satellite pass and the tide gauge station. We show that even if this is not the case, the satellite altimetric observations enable correction of differential tide gauge rates for the effects of sea surface rate inhomogeneities.  相似文献