1,721,086 research outputs found
Combined geochemical and isotopic analyses refine the tephrostratigraphic correlations on marker tephra layers from southern Italy lacustrine and marine sequences
No full textTrace element abundance and isotopic composition determinations of distal tephra levels is not currently a routine
analysis, so the main objective of this work was to obtain full geochemical and isotopic data on well-known
regional markers, aiming at enriching the comparison data-base for future tephrostratigraphic investigations. We
chose to work on distal tephra embedded in the San Gregorio Magno (SGM) lacustrine sequence (Campania,
Southern Italy) because its high sedimentation rates, should make it easier to avoid the problems linked to the
mixing of volcanic fragments related to different explosive events occurred very close in time. Where necessary,
due to the lack of data on comparison tephra from literature, marine distal equivalent were also fully characterized.
The main tephra layers extracted from both sequences, already characterized as to major element composition
(Munno and Petrosino, 2007; Morabito et al.,2014; Petrosino et al., 2016), were analyzed through LA-ICP-MS
to evaluate the abundance of trace elements. The isotopic composition has been measured on a hand-picked glass
amounts and when possible on minerals. The results of these analyses made it possible to refine some correlations
previously hypothesized, as that of sample SGM16, which definitely results the distal counterpart of Monte
Epomeo eruption of Ischia Island, aged ca. 55 ka, and well repeats the composition of the widespread tephra
marker Y-7. The bimodal composition of layer SGM11 is confirmed by the trace element abundance, and only one
of the two compositions (Na2O/K2O ca. 0.45) fully corresponds to that of marker X-5 (ca. 105 ka), here firstly
fully characterized in a marine sequence from a Tyrrhenian sea core. The glass fragments displaying a different
chemical composition (Na2O/K2O ca. 0.9) are probably the product of the reworking of the slightly older tephra
SGM10, the distal counterpart of marker X-6 (ca. 109 ka). Few tephra layers are deeply altered, as evidenced
by the high amount of clay minerals found by XRD analyses and for such a reason the results of 87Sr/86Sr and
143Nd/144Nd isotopic analysis on their glasses were not reliable. To bypass the problems linked to secondary
alteration, where possible, we analyzed feldspar crystals, less prone than glass to chemical alteration, and obtained
better results. In conclusion, the data produced in this work highlight that the full geochemical characterization of
tephra levels, integrated by isotopic data, makes it possible to identify their source and, in most cases, to correlate
them to a specific well known eruptive event.
Morabito, S., Petrosino, P., Milia, A., Sprovieri, M., Tamburrino, S. (2014). A multidisciplinary approach
for reconstructing the stratigraphic framework of the last 40ka in a bathyal area of the eastern Tyrrhenian Sea.
Global and Planetary Change, 123, 121-138.
Munno R., Petrosino P. (2007). The late Quaternary tephrostratigraphical record of the San Gregorio Magno basin
(southern Italy). Journal of Quaternary Science, 22, 247-266.
Petrosino, P., Morabito, S., Jicha, B. R., Milia, A., Sprovieri, M., Tamburrino, S. (2016). Multidisciplinary
tephrochronological correlation of marker events in the eastern Tyrrhenian Sea between 48 and 105 ka. Journal of
Volcanology and Geothermal Research, 315, 79-99
Enhancing Social Resilience Through Fruition of Geological Heritage in the Vesuvio National Park
No full textThe Vesuvio National Park, established in June 1995, is the green area closest to Napoli megacity, which suffers the absence of urban green spaces, and could hence offer to citizens the opportunity to enjoy healthy places in a peculiar environment as the landscape of an active volcano. We here propose two trails with several stops, named the Ancient Railway Track and the Valle dell'Inferno. They start from San Sebastiano al Vesuvio and Ottaviano towns, located on two opposite sides of northern Somma-Vesuvio area, and are both directed towards the Vesuvio crater. Along the trails the visitors can enjoy several volcanic forms and products (the Somma caldera rim, dykes, lava domes, ropy lava flows, pyroclastic fall deposits) together with historical remains, as the Cook Railway track, and the typical botanic association, the Mediterranean bush. The stops were illustrated with panels describing in detail both geological and landscape features with pictures and simple text boxes, clear and engaging for a wide
set of excursionists of different age and cultural background. The quality of the two trails was assessed through a quantitative evaluation of the single stops considering the different typologies of expected visitors. The project of promotion and fruition of green spaces in an active volcanic area here proposed contributes to encourage healthy living and raise well-being and could represent one of the means to achieve a better level of resilience for a society exposed to high volcanic risk
PDC-BuilD framework: Assessing building damage probability for pyroclastic currents of a small-size explosive eruption at Campi Flegrei (Southern Italy)
No full textA methodology for the evaluation of damage that the buildings exposed to pyroclastic currents from a possible small-size eruption at Campi Flegrei could suffer is proposed. It was implemented in a structured GIS framework named BuilD (Building Damage) that integrates spatial and no-spatial data and allows to quantify and map the differences in building composition of censual districts and the damage they could undergo. BuilD uses the fragility curves to assess the damage at censual district scale and requires as input data the building features (ISTAT data and Google Earth images) and the dynamic pressure exerted by Pyroclastic Density Currents. 16 maps of percentage probability of exceeding a damage threshold resulting from 4 increasing damage levels by an eruption occurring at 4 hypothetical volcanic vents were drawn. In the single map, five classes (from high to very low) depict the spatial distribution of potential harms that the built environment could suffer. The methodology is implemented for the knowledge of the current status of the built environment; it can be easily managed also by non-technical stakeholders, exported in areas with similar requirements and profitably used for other hazards. The BuilD frame is scalable to larger areas at risk, keeping the censual districts, available for the whole European territory, as the minimum territorial reference units, useful for comparisons of building damages at regional scale. The produced maps can be used for addressing available funds to ameliorate the structural features of the buildings and to support local authorities in better land management and land use
Valenza socio-culturale del patrimonio geologico nelle aree vulcaniche attive della Baia di Napoli
No full text
The Effectiveness of Geotrails to Support Sustainable Development in the Campi Flegrei Active Volcanic Area
No full textThe fruition and protection of natural heritage to restore cultural identity and promote the regeneration of a marginal urban area fully comply with the targets of sustainable development. With this in mind, we propose a cultural trail in the outskirts of the metropolitan area of Naples, which includes a feld tour with several stops outstanding for geological and landscape value and a virtual tour of an ancient underground quarry, from which piperno, a unique pyroclastic rock, was exploited in the past centuries. The educational purpose of the tour is twofold. On the one hand, it leads people to achieve a better understanding of the geological features of the Campi Flegrei territory, which is essential to raise the awareness of the potential hazards it poses and to improve the resilience of those communities. On the other hand, the tour should provide a signifcant opportunity to get in touch with archeologic and historic remnants worthy of preservation, which help develop a sense of belonging to places. Visitors can also enjoy green spaces in an urban area, observe plant species typical of the Mediterranean environment, and, in the process, learn how the regeneration of semi-abandoned areas with endemic vegetation can help reduce the negative consequences of land degradation exacerbated by climate change. The geotrail fruition can improve well-being and strengthen the relationship between people and territory and, as a fnal spillover, create new low-impact income-producing activities. All these outcomes add up in supporting sustainable development in a marginal urban area, where liveability is made much more difcult by the impending volcanic risk
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A methodology for the evaluation of long-term volcanic risk from pyroclastic flows in Campi Flegrei (Italy),
No full textElementi per possibili correlazioni tra successioni medio-pleistoceniche marine (area di Montalbano) e continentali (area di Venosa), affioranti nell’Avanfossa Bradanica e le vulcaniti del Monte Vulture (Italia meridionale)
No full text- …
