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Towards a probabilistic risk analysis due to volcanic-hazards at Mount Etna
No full textMount Etna is the largest active volcano in Europe and is renowned for its effusive and explosive eruptions, frequently accompanied by intense seismic activity. The densely urbanized area of Eastern Sicily (Italy), situated on the flanks of Mt. Etna, has been the focus of an innovative and comprehensive research project aimed at evaluating the potential volcano hazards and subsequent risks. Hazard scenarios were generated within the research project PANACEA (Probabilistic AssessmeNt of volCanorelated multi-hazard and multi-risk at Mount EtnA) and they have been effectively employed in risk assessment for built-up areas and lifelines. The risk analyses were conducted for lava flow, tephra fall and volcanic earthquake hazards. Risk scenarios were assessed at different spatial scales, from the local one (at the resolution of the census track) to the sub-regional scale, defined as the union of some municipalities. Probabilistic damage scenarios were calculated with the aim of conducting a multi-hazard risk analysis, estimating direct losses in terms of structural damage, casualties and loss of functionality. A few examples of risk assessment are presented here to test the last step of the whole process developed in PANACEA.PublishedOSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Large, multilevel magmatic intrusions as an important carbon degassing source in a nonvolcanic setting
No full textMagmatic intrusions in nonvolcanic areas are believed to cause extensive CO2 degassing
and seismicity. However, the size, geometry, and spatial relationships of these hypothesized
intrusive bodies remain unclear due to a lack of high-resolution geophysical data, especially in
Northeast China sedimentary basins. Here, we present a three-dimensional electrical resistivity
model based on magnetotelluric data from the Songliao Basin in Northeast China. The model
shows a low-resistivity anomaly at the Moho depth vertically connecting to two shallower, sill-
like anomalies in the crust. These anomalies are interpreted as multilevel basaltic intrusions,
with the mid-crust sills estimated to contain up to 150 km3 of melt. The layering of the crust,
as well as the level of neutral buoyancy, plays a critical role in controlling the geometry and
depth of the intrusions in the basins. Seismicity, high heat flow, and CO2 degassing indicate
that this huge magmatic system, although located in a nonvolcanic area, is still active.PublishedOSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Constraining the early stage of the post-orogenic extensional tectonics in central Italy: New evidence from a long sediment core from the tectonically active L’Aquila Basin
No full textThe central Apennines are among the most
seismically active sectors of the central Mediterranean
region, as testified by the recent sequence
of Mw >6 earthquakes (L’Aquila Mw
6.3, 6 April 2009; Amatrice Mw 6.2, 24 August
2016), that struck the region. Although
many recent studies have focused on the
recent history of the active and seismogenic
faults, due to the poor understanding on the
age of the fault-bounded intermontane basins
and on the early stage of their continental
deposition, less is known about the faults’
long-term behavior.
To try to fill this knowledge gap, we analyzed
a long sediment core (230 m depth,
Castelnuovo 1 borehole; CN-1) recovered
from the infill of the Plio-Pleistocene
tectonically active L’Aquila Basin (Paganica–
San Demetrio–Castelnuovo [PSC]
Sub-basin) by employing 40Ar/39Ar dating,
magnetostratigraphy, multiproxy paleoclimatic
data (palynological analyses, pollen
temperature index and clumped isotopes),
and astrocyclostratigraphy.
Combining the results from the CN-1
pollen record, 40Ar/39Ar dating of a tephra
(1.77 ± 0.15 Ma), and magnetostratigraphy
of the CN-1 sediment core, we can refer the
longest normal polarity interval (N3) to the
Olduvai subchron, which we use to constrain
the CN-1 age model. Moreover, spectral
analysis of the CN-1 calcimetry data series
shows the presence of 13 obliquity-modulated
cycles, resulting in an age of ca. 1490
ka for the top of the core and an age of ca.
2027 ka for its base. This time span encompasses
Marine Isotopic Stages (MIS) 50–75.
The occurrence of lacustrine ostracod fauna
since the lowermost portion of the CN-1 core
points to the presence in the PSC Sub-basin,
already at 2 Ma, of a well-developed intermontane
lake. Both pollen assemblages and
clumped isotopes show warm-to-cold climate
changes along the CN-1 sediment core, with
clumped-isotope–derived temperatures of
the lake waters of 15.4 ± 1.6 °C (MIS 53) and
11.5 ± 1.3 °C (MIS 52), whereas temperatures
of 21 ± 1.7 °C and 15.6 ± 1.7 °C correspond
respectively to MIS 67 and MIS 64.
The PSC Sub-basin shows a complex subsurface
architecture, with highs and depocenters
showing maximum thickness of the
lacustrine deposits up to 510–450 m. Considering
that the CN-1 age model points to a
sedimentation rate of 0.3 mm/yr for the deep
lacustrine deposits, the onset of the continental
sedimentation in the L’Aquila intermontane
basin started at ca. 3.2–3.0 Ma.
This post-orogenic extensional domain
responsible for the onset and subsequent development
of the L’Aquila intermontane basin
is still active, representing an archive of
∼3 m.y. of continued crustal extension from
one of the most seismically active sectors of
the central Mediterranean region.PublishedOSA1: Variazioni del campo magnetico terrestre, imaging crostale e sicurezza del territorioJCR Journa
The liquefaction evidences following the 2020 Petrinja earthquake (Pannonian basin, Croatia): A full database and insights for phenomena comprehension
Get PDFThe 2020 MW 6.4 Petrinja (Croatia) earthquake induced extensive and diversified
liquefaction and lateral spreading phenomena within ’ 20 km radius from the
epicenter. A detailed investigation from field and Unmanned Aerial Vehicle (UAV)
surveys was carried out by a European researcher team (EUTeam) in the months
following the mainshock. This work focuses on 61 surveyed sites: field observations
were coupled with laboratory tests for soil classification and sediment composition.
The adopted procedure provides an in-depth geological and geotechnical
characterization of the liquefied sites in the Petrinja region. The liquefaction
evidences are mainly associated to alluvial plain environments, in particular to
meander paleochannels, and the ejected material is predominantly siliciclastic, made
up of very rounded quartz-rich lithics. Few sites are dominated by angular
carbonate rock fragments, related to liquefaction in cataclastic deposits along
tectonic fractures. The ejected sediment includes a wide range of grain-size from
silt to gravel. The peculiar presence of gravel in the liquefied deposits (up to 28% in
some samples) confirms the need of expanding the grain-size boundaries for
liquefiable coarse-grained gravelly soils. The information gathered from the postearthquake
surveys and from the sedimentological and geotechnical analysis for
each studied site were compiled in organized data sheets, providing a striking
instrument for in-depth earthquake studies, both for geological and geotechnical
engineering purposes. The format defined for the data sheet can be functional and
applicable also in liquefaction studies from different geological and depositional
settings.PublishedOST2 Deformazione e Hazard sismico e da maremotoOST3 Vicino alla fagliaJCR Journa
Unveiling the largest (M7) pre-Campanian Ignimbrite event in the Campi Flegrei explosive history: the Maddaloni/X-6 eruption (~109 ka)
No full textThe Campi Flegrei caldera (Italy) is among the most productive volcanoes of the Mediterranean area. However, the volcanic history preceding the VEI 7 Campanian Ignimbrite eruption (~40 ka) is still poorly constrained. Here, we use a tephra dispersal model to reconstruct the eruption source parameters of the Maddaloni/X-6 eruption (~109 ka), one of the most widespread Late Pleistocene Mediterranean marker tephra from Campi Flegrei. Our results suggest that the eruption was characterized by an early Plinian phase involving ~6 cubic kilometers (within the range of 3-21 cubic kilometers) of magma, followed by a co-ignimbrite phase erupting ~148 cubic kilometers (range of 60-300 cubic kilometers). This ranks the Maddaloni/X-6 as a high-magnitude (M7.6) eruption, resulting at least as the second largest known event from Campi Flegrei. This study provides insights into the capability of the Campi Flegrei magmatic system to repeatedly generate large explosive eruptions, which has broad implications for hazard assessment in the central Mediterranean area.PublishedOSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
The Italian Archive of Historical Earthquake Data, ASMI
No full textASMI, the Italian Archive of Historical Earthquake Data, is a data collection distributed online that provides seismological data on more than 6600 earthquakes that occurred in the Italian peninsula and surrounding areas from 461 BC to the present day, based on more than 460 seismological data sources. ASMI is the Italian node of AHEAD, the European Archive of Historical Earthquake Data, which is, in turn, the European node providing data on historical earthquakes to EPOS ERIC, the 10 European Plate Observing System, a European Research Infrastructure Consortium. ASMI distributes earthquake parameters, sets of macroseismic intensity data and other details about earthquake effects, together with the bibliographical reference of the data source and, if possible the data source itself. ASMI's web portal allows users to query the data by earthquake or by data source, and to download the earthquake parameters and macroseismic intensities and represent them on interactive maps and tables. ASMI is updated regularly with new data on past and recent earthquakes. ASMI is the basic source of data for the Italian 15 Macroseismic Database (DBMI) and the Parametric Catalogue of Italian Earthquakes (CPTI). This article describes the archive content and structure, its main features and functionalities, and its potential seismological research applications.PublishedJCR Journa
Geoethics Supporting Geotourism Modelling: Assessing Karst Geosites and Management Practices in Serbia and Montenegro
No full textThis study presents the development of a comprehensive Karst Geoethics Assessment Model (KGAM) that integrates karst vulnerability, conservation practices, and tourism utilisation to promote a geoethical approach to International Best Practice (IBP), ensuring appropriate karst site management. The primary goal is to assess the performance from a geoethical perspective of sustainable management strategies for geologically significant destinations. As a case study, eight karst geosites in Serbia and Montenegro were subject to evaluation using four sets of indicators: Karst Vulnerability (KV), Human Activities (HA), Conservation Efforts (CE), and Geoethical Tourism Performance (GTP). Results reveal a range of vulnerabilities, conservation statuses, and tourism practices across the geosites, highlighting significant challenges, particularly in waste management, biodiversity loss, and geoethical awareness of local communities. Whilst a few geosites demonstrate robust conservation efforts and low human interference, others face high vulnerabilities from tourism and urban activities. The study emphasizes the need for specialised management strategies, educational programs, and geoethical practices to ensure the sustainable management and conservation of karst geosites. Recommendations for targeted interventions, stakeholder involvement, and geoethical tourism promotion are provided to improve the long-term sustainability of these unique landscapes.PublishedN/A or not JC
Benchmarking Non-Hydrostatic Tsunami-HySEA and Multilayer-HySEA Codes for Tsunami Hazard Assessment
No full textPublishe
Application of the conditional spectrum approach for the selection of ground motion time histories in vast areas: an example in the Lazio region
No full textSelection of accelerometric time histories is a fundamental step in seismic microzonation studies as well as in structural and ground response analyses. In this study we apply the procedure of Mascandola et al. (2020) for record selection in vast areas to the Lazio region (Central Italy). Unlike the original approach, we apply a different unsupervised clustering algorithm to divide the study area into mesozones, defined as zones that are homogeneous in terms of seismic hazard. Moreover, we apply the conditional spectrum () method for the selection of ground motion time histories. Concerning the zoning of the study area, two clustering algorithms are compared: K-means and Spectral clustering. We found that the latter provides a zonation that is more consistent with the spatial distribution of the seismic hazard as well as of hazard disaggregation and is therefore suggested for record selection in vast areas. For each mesozone, two conditional spectra (computed for two conditioning oscillator periods) are then defined and adopted as reference for the selection of real accelerometric records. The latter are selected from a large sample of accelerograms that include earthquakes having magnitude and distance consistent with the seismic scenarios controlling the hazard. The article ends with a comparison of different techniques for the selection of real acceleration time histories. We analyze the impact of different sets of accelerograms on the ground response of two soil profiles resonating at the same periods used for conditioning the spectra (i.e., 0.2s and 1.0s). The results confirm that the conditional spectrum approach is targeted at oscillatory systems with a well-specific vibration period, for which the conditional spectrum might provide more conservative ground motions than the standard uniform hazard spectrum approach. Conversely, the latter approach is preferable for dynamic analyses of systems where more than one response period is relevant. Furthermore, our findings show that dividing the area into mesozones and selecting accelerograms using a single reference spectrum for each mesozone produces results comparable to those obtained through conventional methods based on site-specific record selection. Therefore, our approach can significantly streamline the selection of accelerometric time histories, especially in the case of vast areas.PublishedJCR Journa
Migrazione della linea di costa dovuta a processi di tettonica attiva: una narrazione cartografica in ambiente GIS
No full textPublishedOST2 Deformazione e Hazard sismico e da maremot