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Roberta Marciano Rosalba Munno Paola Petrosino Nicoletta Santangelo Antonio Santo Igor Villa 《Journal of Volcanology and Geothermal Research》2008
The results of stratigraphic and tephrostratigraphic analyses of several pyroclastic levels, collected along the coastal sector of the Cilento region (southern Italy), are presented. Some of these levels are here described for the fist time, others, already known in literature, were reconsidered in order to better understand their stratigraphic position and to point out the possible volcanic sources. 相似文献
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Emanuele Perinati Chris Tenzer Andrea Santangelo Konrad Dennerl Michael Freyberg Peter Predehl 《Experimental Astronomy》2012,33(1):39-53
The pn-CCD cameras at the focal plane of the eROSITA space observatory will be the first X-ray (0.2?C12?keV) detector to operate in a L-2 orbit. Therefore, no direct information of instrumental non X-ray background (NXB) is available to make predictions for eROSITA. Since, in general, the instrumental NXB experienced in orbit has a major impact on the overall sensitivity of the cameras, we investigated and modeled the L-2 radiation environment and its interaction with the eROSITA mass distribution and cameras, in order to quantify the expected pn-CCD NXB level. We obtain an average value of NXB ??25% lower than that observed by the pn-CCDs on-board the XMM-Newton satellite, which is placed in a Highly Elliptical Orbit (HEO). We discuss this result in light of the differences between the L-2 and HEO space environments. 相似文献
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Karst collapse sinkholes (KCS) are a peculiar karst morphology resulting from the collapse of the topographic surface caused by subsurface karstification. In the Southern Apennines these phenomena are not randomly distributed but concentrate in several zones, named High Sinkhole Concentration Areas (HSCA), showing peculiar geological, structural and hydrogeological conditions. Gas vents and mineral springs occur widely in these HSCA, and are often stricty related to the KCS. Starting from four representative areas, the aim of this study is to ascertain if there is a genetic link between peculiar mineralogical vs geochemical features of densely fractured/altered rocky masses in KCS, gas vents/springs occurrences and diffuse hypogenic karstification. By means of a multidisciplinary approach (geological/geomorphological, mineralogical and geochemical) we selected and analysed four different kinds of samples related to KCS, gas vent and spring occurrences: (i) altered to deeply altered limestones sampled in the sinkholes; (ii) unaltered limestones sampled in close proximity to sinkhole areas; (iii) gypsum-rich crusts/patinae, precipitated near to gas vents; (iv) gypsum- and calcite-rich precipitates occurring at springs or inside caves. Among neoformed non-carbonate minerals, gypsum is virtually ubiquitous, halides (fluorite, halite, sylvite) also occur in small to trace amounts. The mineralogical assemblages of the different samples show similarities and may also be compatible with hypogenic speleogenesis and with a process of alteration of the carbonate bedrock by means of uprising mineralizing fluids along structural discontinuities. Stable isotopic compositions (S, O) display strong variability in δ34S and δ18O for sulfate in the different areas, but a deep-seated sulfur source can be hypothesized for many of the studied KCS-related samples. This study has important implications for the relationships between areas of high concentration of sinkholes, regional fault systems, mechanical characteristics of rocks and the high seismicity typical of these areas of the Southern Apennines. © 2018 John Wiley & Sons, Ltd. 相似文献
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Landslide distribution and size in response to Quaternary fault activity: the Peloritani Range,NE Sicily,Italy 
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下载免费PDF全文 Francesco Bucci Michele Santangelo Mauro Cardinali Federica Fiorucci Fausto Guzzetti 《地球表面变化过程与地形》2016,41(5):711-720
Landslides contribute to dismantle active mountain ranges and faults control the location of landslides. Yet, evidence of the long‐term, regional dependency of landslides on active faults is limited. Previous studies focused on the transient effects of earthquakes on slope stability in compressive and transcurrent regimes. Here we show that in the Peloritani range, NE Sicily, Italy, one of the fastest uplifting areas in the Mediterranean, a clear geographical association exists between large bedrock landslides and active normal faults of the Messina Straits graben. By interpreting aerial photographs, we mapped 1590 landslides and sackungs and 626 fault elements and their facets in a 300 km2 area in the eastern part of the range. We used the new landslide and fault information, in combination with prior geological and seismic information, to investigate the association between bedrock landslides and faults. We find that the distribution and abundance of landslides is related to the presence of large active normal faults, and matches the pattern of the local historical seismicity. Landslide material is more abundant along the East Peloritani Fault System where the long‐term activity of the faults, measured by the average yearly geological moment rate, is larger than in the West Peloritani Fault System where landslides are less abundant. Along the fault systems landslide material concentrates where the cumulated fault throws are largest. We conclude that large landslides and their cumulated volume are sensitive to local rates of tectonic deformation, and discriminate the deformation of the single fault segments that dissect the Peloritani range. Our findings are a direct test of landscape evolution models that predict higher rates of landslide activity near active faults. Our work opens up the possibility of exploiting accurate landslide and fault maps, in combination with geological and seismic information, to characterize the long‐term seismic history of poorly instrumented active regions. © 2015 The Authors Earth Surface Processes and Landforms Published by John Wiley & Sons Ltd 相似文献
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Sponges Inhabiting a Mediterranean Red Coral Population 总被引：2，自引：0，他引：2
Abstract. A coastal red coral [Corallium rubrum (L.)] population, whose age structure and demographic parameters have been previously analysed, harbours 10 species of endobiotic sponges. This sponge assemblage differs considerably from that inhabiting other calcareous substrata of the surrounding area, suggesting some selectivity for red coral. The two most common endobiotic species, Spiroxya heteroclita T opsent and Cliona sarai M elone , are described in detail. The percentage of infested coral colonies increases according with colony age, with a sharp increment at four years. An increase in coral colony mortality observed at this age may be related to the increment of endobiotic sponge infestation. 相似文献