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Seismic response and ambient vibrations of a Mediaeval Tower in the Mugello area (Italy)
No full textThis paper describes the experimental campaigns on the Tower of the Palazzo dei Vicari in Scarperia, a village in the
Mugello area (Tuscany) exposed to high seismic hazards. The first campaign was carried out from December 2019 to Janu-
ary 2020, and the Tower underwent the so-called Mugello seismic sequence, which featured an M 4.5 earthquake. Other
ambient vibration tests were repeated in June 2021 and September 2023 when another seismic sequence struck the area
near Scarperia. These tests aimed to characterise the Tower’s dynamic behaviour under ambient and seismic excitations
and check the response of the Tower over time. The experimental results were then used to calibrate a finite-element model
of the Tower and estimate its seismic vulnerability. Several numerical simulations were conducted on the calibrated model
using the NOSA-ITACA code for nonlinear structural analysis of masonry buildings. The dynamic behaviour of the Tower
subjected to a seismic sequence recorded in 2023 by a seismic station at the base was investigated by comparing the velocities
recorded along the Tower’s height with their numerical counterparts. Furthermore, several pushover analyses were conducted
to investigate the collapse of the Tower as the load’s distribution and direction variedIn pressJCR Journa
Rayleigh wave attenuation and phase velocity maps of the greater Alpine region from ambient noise
No full textWe use seismic ambient noise data from 724 publicly available broadband seismic stations across central Europe to create detailed phase velocity and attenuation maps of Rayleigh waves, focusing on short periods down to 3 s. We interpret these maps in terms of the underlying physical processes relevant to the nature of continental crust. Through a regionalized interpretation based on tectonic settings, we highlight the significant role of fluid-filled fractures in the attenuation of surface waves. Our findings indicate a close connection between the time elapsed since the last tectonic activity in the European crust and the attenuation coefficient values. Additionally, we observe a pronounced decrease in attenuation coefficient values at periods below 6 s. The anti-correlation between attenuation coefficient and phase velocity in recently active tectonic regions suggests that fluid-filled fractures are likely the dominant factor governing seismic attenuation in the European crust.Grant of Excellence Departments, MIUR-Italy (ARTICOLO 1, COMMI 314-337 LEGGE 232/2016).
INGV Pianeta Dinamico 2023-2025 (grant no. CUP D53J19000170001) supported by the Italian Ministry of University and Research (“Fondo finalizzato al rilancio degli investimenti delle amministrazioni centrali dello Stato e allo sviluppo del Paese, legge 145/2018”) - Project MT_ADRIABRIDGE.Published29164OST1 Alla ricerca dei Motori GeodinamiciJCR Journa
A fast compilation of the VONA messages using a computer-assisted procedure
No full textMt. Etna, in Italy, is one of the most active volcanoes in the world, producing several explosive events in recent years. Those eruptions form high eruption columns that often reach the top of the troposphere (and sometimes even the lower part of the stratosphere) and create several disruptions to air traffic, mainly to the Fontanarossa International Airport in Catania, which is about 20 NM (~ 37 km; NM = Nautical Miles) away from the summit craters and is located in the main wind direction. In Italy, the institution responsible for volcano monitoring is the Istituto Nazionale di Geofisica e Vulcanologia (INGV). In 2007, the INGV, Osservatorio Etneo (INGV-OE) in Catania was appointed as “State Volcano Observatory” (SVO) and, in 2014, sent the first Volcano Observatory Notice for Aviation (VONA) message. Since that moment, several VONA messages have been sent, mainly due to the high frequency of Etna activity. In order to facilitate and speed in the generation and the dispatch of the VONA messages, a computer-assisted procedure has been designed and built to help the work done by the volcanologist on duty and by the two shift workers of the 24/7 Control Room of INGV-OE. Consequently, information on the explosive activity can be quickly provided to the Volcanic Ash Advisory Center (VAAC) in Toulouse and national air traffic offices, reducing risks to aviation operations. In this work, we describe how the computer-assisted procedure works, addressing the main advantages and possible improvements. We retain that a similar approach could be easily applied to other volcano observatories worldwide.Published39OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Short-term magma-carbonate interaction: A modelling perspective
No full textShort-term interaction of magma with crustal carbonates can affect a volcano's eruptive style and drive even low-viscosity magmas toward large explosive eruptions. Only a few studies have focused on short-term magma-carbonate interaction under controlled laboratory conditions and the physical processes behind the experimental observations are still poorly understood. In this work, we present the first numerical modelling study of short-term magma-carbonate interaction and provide an interpretative framework for experimental and field observations. We developed thermodynamic and dynamic models for carbonate dissolution and mixing and mingling between contaminated magma pockets and host magma. We find that mixing and mingling can play a central role in modulating the efficiency of volatile exsolution. The increasing viscosity of the host melt slows down melt mingling and hence the mixing process, limiting volatile exsolution. Less efficient mixing and mingling could allow the fingerprints of short-term magma-carbonate interaction to be preserved in volcanic and intrusive rocks. Finally, we highlight that the mechanism and timescale of magma-carbonate interaction open a key question about the anomalous high mobility of CaO during carbonate dissolution.Published118592OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Ground Penetrating Radar (GPR) Investigations in Urban Areas Affected by Gravity-Driven Deformations
No full textThe 1980 Ms 6.9 Irpinia earthquake was responsible for the activation or reactivation of numerous gravitative deformations mainly hosted by clayey lithotypes, affecting wide areas of Benevento Province and the Sele and Ofanto R. Valleys. The case of Calitri offers valuable insights into a methodological approach to studying mass movements affecting human settlements. Post-earthquake investigations in Calitri involved extensive geognostic boreholes and in situ surveys, providing substantial data for lithological characterization and landslide modeling. Additionally, over the past two decades, satellite-based techniques have supported the mapping and characterization of ground deformations in this area, improving our understanding of spatiotemporal evolution. Despite these efforts, a detailed subsurface comprehensionof the tectono-stratigraphy and geometriesof gravity-induced deformation remains incomplete. This study aims to enhance our knowledge of gravity-driven deformations affecting urban areas by using deep-penetrating GroundPenetrating Radar (GPR) surveys to identify landslide-related structures, rupture surfaces, and lithological characterization of the involved lithotypes. The integration of GPR surveys with classical morphotectonic analysis led to the delineation of the main subsurface discontinuities (stratigraphy, tectonics, and gravity-related), correlating them with available geognostic data. This approach provided non-invasive, detailed insights into subsurface features and stands out as one of the rare case studies in Italy that employed the GPR method for landslide investigations.Published222JCR Journa
Constraining the end of the Last Interglacial (MIS 5e) relative sea-level highstand in central Mediterranean: New data from Grotta delle Capre, central Italy
No full textThe current rapid change of the Earth’s climate has resulted in an increasing interest for the past warm periods as
potential long-term scenarios of the effects of the present global warming. The last such a period occurred
129–116 ka, known as the Last Interglacial (LIG), when the continental ice volume was significantly smaller than
present, leading to a global sea-level (GSL) higher than present one. Detailed morpho-stratigraphic data, supported
by a robust U/Th chronology, from Grotta delle Capre, central Italy, provided new chronological insights
on the relative sea-level (RSL) dynamic during the LIG in the Mediterranean region. Our results indicate that, on
Tyrrhenian Sea coasts of the central Italy, after having stationed at ~9 m a.s.l., the LIG RSL fell at an elevation
<3 m a.s.l. as early as before 123 ka, and then no longer rose above this elevation either during the later stages of
the LIG or afterwards. The results match previous studies based on U/Th dating of terrestrial limiting points from
Grotta Infreschi, ~200 km SE from Grotta delle Capre along the same Tyrrhenian Sea coasts, and are in
agreement with the Red Sea RLS and GSL records and the probabilistic LIG sea level assessments based on
globally distributed records. On the other hand, our reconstruction is not supported by implications of U/Th
dating of corals and phreatic overgrowth on speleothems from the Balearic Island of Mallorca. Such an inconsistency
in the overall knowledge around the LIG RSL reconstruction results in a high uncertainty in modelling the ice and sea-level dynamic during this warm period, which needs to be reduced through more and more highresolution, stratigraphic and chronological investigations of the morphological and sedimentary sea-level records.Published104321OSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa
A novel multiple-expert protocol to manage uncertainty and subjective choices in probabilistic single and multi-hazard risk analyses
No full textIntegrating diverse expert opinions in hazard and risk projects is essential to managing subjective
decisions and quantifying uncertainty to produce stable and trustworthy results. A structured
procedure is necessary to organize the gathering of experts' opinions while ensuring transparency,
accountability, and independence in judgements. We propose a novel Multiple-Expert
management Protocol (MEP) to address this challenge, providing procedural guidelines for conducting
single to multi-hazard risk analyses. MEP establishes a workflow to manage subjectivity
rooted in (i) moderated and staged group interactions, (ii) trackable blind advice through written
elicitations with mathematical aggregation, (iii) participatory independent review, (iv) close cooperation
between scientific and managerial coordination, and (v) proper and comprehensive
documentation. Originally developed for stress testing critical infrastructure, MEP is designed as
a single, flexible, technology-neutral procedural workflow applicable to various sectors. Moreover,
its scalability allows it to adapt from high to low-budget projects and from complex probabilistic
multi-hazard risk assessments to standard single-hazard analyses, with different experts'
degree and type of involvement depending on available funding and emerging controversies. We
present two compelling case studies to showcase MEP's practical applicability: a multi-hazard risk
analysis for a port infrastructure and a single-hazard regional tsunami hazard assessment.Published104641JCR Journa
On the retrieval of cloud optical thickness from spectral radiances - A sensitivity study with high albedo surfaces
No full textMeasurements of spectral zenith radiance in the 320–950 nm wavelength range have been carried out since 2021 at the Thule High Arctic Atmospheric Observatory (THAAO,
https://www.thuleatmos-it.it/
, 76.5° N, 68.8° W, 225 m a.s.l) located in Pituffik, northern Greenland. This study evaluates whether such observations could provide, in principle, scientifically meaningful cloud optical depth (τ) estimates, what would be the limitations, which are the necessary auxiliary measurements, and which radiance wavelengths would be better suited for the goal. Although clouds play a critical role in the Arctic, a climatology of τ in high albedo conditions is particularly difficult to obtain. THAAO might have the instrument capabilities to provide such a long-term dataset. We use a radiative transfer package to simulate visible spectra with different cloud and surface conditions, assuming homogeneous overcast sky and liquid water clouds of fixed geometrical thickness. Simulations are run to reproduce typical conditions encountered at THAAO when measurements are carried out. We find that the assumption of a broadband albedo instead of a spectrally-resolved one is the source of the largest uncertainties. Tests on size and phase of cloud particles showed that a 50% uncertainty in reff leads to a ∼10% error in τ, and that a 10% contamination of ice crystals in a low-level liquid water cloud leads to an error in τ estimates of less than 5%. All the tests showed that the most critical τ range is between the thin and thick cloud regimes (τ ∼ 7–15), where the retrievals can be less reliable. Otherwise, tests suggest that in the environmental conditions that characterize late spring and summer at THAAO, and given the observatory measurements capabilities, estimates of τ for low-level clouds could be accurately retrieved both in high and low surface albedo conditions by means of zenith radiance measurements in the UV-Vis-NIR range.This research has been supported by the Italian Antarctic Research Program (PNRA) through project PNRA18_00122 "CLouds And Radiation in the Arctic and Antarctica (CLARA2)" and by the Italian Arctic Research Programme (PRA) through project PRA2019-0009 "Effects of Changing Albedo and Precipitation on the Arctic Climate (ECAPAC)". Both PNRA and PRA are programs of the Ministry of University and Research.
The Italian activities at Thule High Arctic Atmospheric Observatory (THAAO) have been supported by the Istituto Nazionale di Geofisica e Vulcanologia (Environment Department) in the framework of the Multidisciplinary Analysis of Climate change indicators in the Mediterranean And Polar regions (MACMAP) project.Published109108OSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa
Lahar events in the last 2000 years from Vesuvius eruptions – Part 1: Distribution and impact on densely inhabited territory estimated from field data analysis
No full textLahars represent some of the most dangerous phenomena in volcanic areas for their destructive power, causing dramatic changes in the landscape with no premonitory signs and impacting the population and infrastructure. In this regard, the Campanian Plain turns out to be very prone to the development of these phenomena, since the slopes of the Somma–Vesuvius and Campi Flegrei volcanoes, along with the Apennine reliefs, are mantled by pyroclastic deposits that can be easily remobilized, especially after intense and/or prolonged rainfall.
This study focuses on the analysis of pyroclastic fall and flow deposits and of the syn- and post-eruptive lahar deposits related to two sub-Plinian eruptions of Vesuvius in 472 CE (Pollena) and 1631. To begin with, historical and field data from the existing literature and from hundreds of outcrops were collected and organized into a database, which was integrated with several new pieces of data. In particular, stratigraphic, sedimentological (facies analysis and laboratory), and archeological analyses were carried out, in addition to rock magnetic investigations and impact parameter calculations. The new data are also referenced to the finding of ash beds in more distal areas, which were included in new isopach maps for the two sub-Plinian eruptions.
The results show that for both eruptions the distribution of the primary deposits is wider than previously known. A consequence of these results is that a wider areal impact should be expected in terms of civil protection, as the sub-Plinian scenario is the reference one for a future large eruption of Vesuvius. Such a distribution of the pyroclastic deposits directly affects the one of the lahar deposits, also because a significant remobilization took place during and after the studied eruptions, which involved distal phreatomagmatic ash. From these integrated analyses, it was possible to constrain the timing of the deposition and the kind of deposits remobilized (pyroclastic fall vs. flow), and it was possible to calculate the velocities and dynamic pressures of the lahars and ultimately infer the lahar transport and emplacement mechanisms.
The multidisciplinary approach adopted in this work shows how it is crucial to assess the impact of lahars in densely populated areas even at distances of several to tens of kilometers from active volcanoes. This especially applies to large parts of the densely populated areas around Somma–Vesuvius up to the nearby Apennine valleys.Published405-436OSV1: Verso la previsione dei fenomeni vulcanici pericolosiOSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Recalibration of the Intensity Prediction Equation in Italy Using the Macroseismic Dataset DBMI15 Version 2.0
No full textWerecomputethecoefficients of the intensity prediction equation (IPE) in Italy using the data of the DBMI15 version 2.0 (v.2.0) intensity database and the instrumental and combined (instrumental plus macroseismic) magnitudes reported by the CPTI15 v.2.0 catalog. Wefollow the same procedure described in the previous article, consisting of a first step in which the attenuation of intensity I with respect to the distance D from macroseismic hypocenter is referred to the expected intensity at the epicenter IE and a second step in which IE is related to the instrumental magnitude Mi, the combined magnitude Mc,the epicentral intensity I0, and the maximum intensity Imax using error-in-variable (EIV) regression methods. The main methodological difference with respect to the original article concerns the estimation of the uncertainty of IE to be used for EIV regressions, which is empirically derived from the standard deviation of regression between IE and Mi and also used for the regressions of IE with Mc, I0,andImax. In summary, the new IPE determined from DBMI15 v.2.0 is I IE−0:0081D−h−1:072 lnD−lnh , in which D p R2 h2 , h = 4.49 km, and IE can be calculated from the intensity data distribution of the earthquake. If the intensity data distribution is not available, IE can be calculated from the following relationships IE −2:578 1:867Mw,IE I0.Published2399–2408OST2 Deformazione e Hazard sismico e da maremotoJCR Journa