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Building materials and decay assessment of the Gerace Cathedral (Reggio Calabria, Southern Italy)
No full textA multi-analytical approach was employed for the first time to study the stone materials, wall paintings and related degradation forms in the Cathedral of Gerace (Reggio Calabria, southern Italy). With an area of around 1898 square meters, the Gerace Cathedral is the largest in Calabria: its construction dates back to the Norman era (between 1085 and 1120), and currently displays distinct features of Greek and Latin architectural orders. Despite having undergone numerous restorations, the church perfectly preserves its original buildings materials. Following an extensive site inspection campaign, supported by the experts dealing with building restoration, several areas were selected for analyses. Both in situ investigations and laboratory tests were carried out on micro-fragments using Non-Destructive and Micro-Destructive Techniques (NDTs and MDTs). The first step involved an inspection through InfraRed Thermography (IRT) in order to map the internal walls of the Cathedral and identify zones with potential degradation phenomena. Subsequently, a more in-depth study was designed based on the thermographic results, and laboratory tests were carried out on micro-fragments and powders to characterize the different kinds of materials (i.e., stones, mortars, plasters and pigments) and decay agents (i.e., salts and efflorescences). Thirty-one samples were subjected to a complementary analytical approach which included Polarizing Optical Microscopy (POM), Ion Chromatography (IC), X-Ray Powder Diffraction (XRPD) and Scanning Electron Microscopy (SEM) coupled with microanalysis (EDS). The results allowed us to preliminarily characterize the different materials from which the Cathedral was built, determine its state of conservation and provide a better knowledge of the entire building, revealing details not visible to the naked eye which are important for future conservation interventions. As for the state of conservation, the integrated use of various techniques enabled the detection of rising damp generally correlated with the occurrence of water infiltration and migration phenomena which appear to affect a large part of the building, causing noticeable damage (i.e., loss of surface material, micro-cracks, white salt efflorescence, etc.). The characterization of the materials carried out on mortars, plasters, and pigments also confirmed the local origin of the raw materials. However, the provenance of the studied marbles and crystalline limestones, could not be established and, therefore, further in-depth studies are required.Publishede02225OSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa
The Erasmus+ BridgET project: A European partnership to renew teaching in marine geosciences
No full textRecent advances in underwater and airborne robotic systems and ocean technologies have
opened new perspectives in marine geology and its applications in the context of coastal and
marine economic activities, whose sustainable development is increasingly acknowledged as a
pillar for the new blue economy. BridgET (Bridging the gap between the land and the sea in a
virtual Environment for innovative Teaching and community involvement in the science of climate
change-induced marine and coastal geohazard) is an EU ERASMUS+ project designed to develop
innovative and inclusive teaching methods to address a growing demand for strategic skills and
scientific expertise in the field of 3D geological mapping of coastal environments. Seamless
integration of the wide variety of multisource and multiscale onshore, nearshore and offshore
geospatial data is indeed one of the main areas for improvement in the implementation of
efficient management practices in coastal regions, where climate change, rising sea level, and
geohazards are considerable environmental issues.
BridgET involves a partnership consisting of six European universities with outstanding expertise
in the study of geological hazards, and climate impacts in marine and coastal areas (i.e., University
of Milano-Bicocca, Italy, Arctic University of Tromsø/CAGE - Norway, National and Kapodistrian
University of Athens - Greece, Kiel University, Germany, University of Liege – Belgium, and the
University of Malta), two Italian research institutes (INGV and INAF) and a German company
(Orthodrone GmvH) specialized in UAS-based LiDAR and photogrammetry data acquisition services and analyses.
Project implementation relies on delivering learning and teaching activities
through dedicated summer schools for MSc students by efficiently combining the partner’s
expertise. Schools focus on giving students a hands-on experience with the variety of methods
and procedures adopted in geospatial data acquisition and processing, including the use of drones
(Uncrewed Aerial System – UAS), acoustic remote sensing techniques and underwater robotic
systems, together with the progress made by computer visions and digital image analysis by
using Artificial Intelligence (AI). Students are also introduced to the opportunity to easily examine
multiple viewing angles of the seabed and coastal 3D surfaces by using immersive and nonimmersive
Virtual Reality (VR), to bring them closer to a more straightforward observation of
geomorphological data and geological phenomena.
The first Summer School was held in Santorini between the 3rd and 14th of October, 2022. It was
attended by 26 students coming from 13 different countries. Teaching and learning activities
included several classrooms, fieldwork, laboratory sessions, and seven seminars and cultural visits
dealing with transversal topics, allowing students to approach an integrated understanding of
human interaction with physical processes from social and economic perspectives. In this
presentation, we give examples of course content used to allow students to develop a deeper
understanding of theoretical and practical knowledge of climate-induced coastal and marine
geohazards. Participants' opinions on the quality of the offered learning/training activities of the
Erasmus+ BridgET Santorini Summer School (collected through a dedicated questionnaire) will also
be presented.
Erasmus+ BridgET Team: Varvara Antoniou, Fabio Luca Bonali, Clara Drummer, Theynushya
Esalingam, Luca Fallati, Susanna Falsaperla, Felix Gross, Hans-Balder havenith, Juri Klusak,
Sebastian Krastel, Iver Martens, Aaron Micallef, Paraskevi Nomikou, Giuliana Panieri, Danilo
Reitano, Julian Teege, Alessandro Tibaldi, Andrea Giulia Varzi, Fabio Vitello, Othonas VlasopoulosPublishedVienna (Austria)OSA4: Ambiente marino, fascia costiera ed Oceanografia operativ
Materials for a Catalogue of Italian Earthquakes. Minor earthquakes in the Asolo area (Northern Italy) (1861-1921)
No full textIn assessing the seismic hazard of an area, and consequently, in risk estimates, a key role is played by the occurrence of strong earthquakes, in this case, the earthquake of 25 February 1695 (Mw 6.4). However, as shown by the MPS19 hazard model [Meletti et al., 2021], the significant increase in hazard values in areas of medium seismicity (e.g. Emilia Romagna), in particular the 10% estimate in 50 years, is determined by the strong improvement of the base data included in the CPTI15 catalogue [Rovida et al., 2022], represented by about a thousand earthquakes re‐evaluated with respect to the previous version, a couple of hundred of which were introduced ex novo in the catalogue.
The present work took into consideration the portion of the Treviso area close to the Venetian Prealps, in particular the area close to the town of Asolo, of which several relatively “minor” earthquakes, included in the CPTI15 catalogue [Rovida et al., 2022] based on super‐expeditious studies, were studied ex novo.
Starting from the preliminary studies available, in‐depth research was carried out going back to the original sources, redetermining the epicentral parameters of each event on the basis of a new data‐set.
As a result of this work, a substantial improvement in the information on each earthquake both in terms of the number of intensity points and the reliability of the estimates has been achieved, as well as making available the transcripts of the entire body of sources and bibliography on the earthquakes considered.Published1-155OST1 Alla ricerca dei Motori GeodinamiciJCR Journa
Modelling Paroxysmal and Mild-Strombolian Eruptive Plumes at Stromboli and Mt. Etna on 28 August 2019
No full textVolcanic eruptions pose a major natural hazard influencing the environment, climate and
human beings at different temporal and spatial scales. Nevertheless, several volcanoes worldwide
are poorly monitored and assessing the impact of their eruptions remains, in some cases, challenging.
Nowadays, different numerical dispersion models are largely employed in order to evaluate the
potential effects of volcanic plume dispersion due to the transport of ash and gases. On 28 August
2019, both Mt. Etna and Stromboli had eruptive activity; Mt. Etna was characterised by mild-
Strombolian activity at summit craters, while at Stromboli volcano, a paroxysmal event occurred,
which interrupted the ordinary typical-steady Strombolian activity. Here, we explore the spatial
dispersion of volcanic sulphur dioxide (SO2) gas plumes in the atmosphere, at both volcanoes, using
the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) considering the
ground-measured SO2 amounts and the plume-height as time-variable eruptive source parameters.
The performance of WRF-Chem was assessed by cross-correlating the simulated SO2 dispersion
maps with data retrieved by TROPOMI and OMI sensors. The results show a feasible agreement
between the modelled dispersion maps and TROPOMI satellite for both volcanoes, with spatial
pattern retrievals and a total mass of dispersed SO2 of the same order of magnitude. Predicted
total SO2 mass for Stromboli might be underestimated due to the inhibition from ground to resolve
the sin-eruptive SO2 emission due to the extreme ash-rich volcanic plume released during the
paroxysm. This study demonstrates the feasibility of a WRF-Chem model with time-variable ESPs in
simultaneously reproducing two eruptive plumes with different SO2 emission and their dispersion
into the atmosphere. The operational implementation of this method could represent effective support
for the assessment of local-to-regional air quality and flight security and, in case of particularly intense
events, also on a global scale.Published5727OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Ultrahigh-precision noble gas isotope analyses reveal pervasive subsurface fractionation in hydrothermal systems
No full textMantle-derived noble gases in volcanic gases are powerful tracers of terrestrial volatile evolution, as they contain mixtures of both primordial (from Earth's accretion) and secondary (e.g., radiogenic) isotope signals that characterize the composition of deep Earth. However, volcanic gases emitted through subaerial hydrothermal systems also contain contributions from shallow reservoirs (groundwater, crust, atmosphere). Deconvolving deep and shallow source signals is critical for robust interpretations of mantle-derived signals. Here, we use a novel dynamic mass spectrometry technique to measure argon, krypton, and xenon isotopes in volcanic gas with ultrahigh precision. Data from Iceland, Germany, United States (Yellowstone, Salton Sea), Costa Rica, and Chile show that subsurface isotope fractionation within hydrothermal systems is a globally pervasive and previously unrecognized process causing substantial nonradiogenic Ar-Kr-Xe isotope variations. Quantitatively accounting for this process is vital for accurately interpreting mantle-derived volatile (e.g., noble gas and nitrogen) signals, with profound implications for our understanding of terrestrial volatile evolution.Publishedeadg2566OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Hydrogeochemical characterization of the alluvial aquifer of Catania Plain, Sicily (South Italy)
No full textA hydrogeochemical study was carried out on the shallow Catania Plain alluvial aquifer, in eastern Sicily to reconstruct
its hydrogeological structure, the meteoric recharge and to assess the infuence of human activities on groundwater. To
characterize the geochemistry of the shallow aquifer, two sampling campaigns were carried out, August–October 2004 and
April–May 2005 in 47 sites distributed throughout the plain. The samples were collected and analyzed for physical–chemical parameters and major ions, as well as stable isotopes (δ18O and δ2
H). Alluvial deposits with heterogeneous grain sizes
constitute the aquifer. Varying conditions of vertical and horizontal permeability lead to the presence of a multilayered aquifer
with diferent conditions of confnement and partial interconnection among layers. The sampled waters were separated into
four groups of diferent compositions due to the water–rock interaction with the diferent lithologies present in and around
the study area. Maps of electrical conductivity and sulfate show a systematic control of land use, in correspondence with
the biggest farms. High sulfate concentration is due to both the natural interaction between local meteoric waters and Etna’s
plume and the mixing with groundwater coming from the area where evaporitic rocks of the Gessoso Solffera formation are
present. In addition, anthropogenic contamination cannot be ruled out. A rain gauge network, consisting of 3 sites located at
diferent altitudes, was installed to collect rain waters to determine isotopic data (δ2
H and δ18O) and to measure the monthly
rainfall amount. Based on the isotopic composition of sampled waters, it has been established that beyond the direct meteoric
recharge, the recharging areas are in the North (Mt. Etna) and the South (Hyblean Plateau).Published1446A. Geochimica per l'ambiente e geologia medicaJCR Journa
Detection of ice core particles via deep neural networks
No full textInsoluble particles in ice cores record signatures of past climate parameters like vegetation dynamics, volcanic activity, and aridity. For some of them, the analytical detection relies on intensive bench microscopy investigation and requires dedicated sample preparation steps. Both are laborious, require in-depth knowledge, and often restrict sampling strategies. To help overcome these limitations, we present a framework based on flow imaging microscopy coupled to a deep neural network for autonomous image classification of ice core particles. We train the network to classify seven commonly found classes, namely mineral dust, felsic and mafic (basaltic) volcanic ash grains (tephra), three species of pollen (Corylus avellana, Quercus robur, Quercus suber), and contamination particles that may be introduced onto the ice core surface during core handling operations. The trained network achieves 96.8% classification accuracy at test time. We present the system’s potential and its limitations with respect to the detection of mineral dust, pollen grains, and tephra shards, using both controlled materials and real ice core samples. The methodology requires little sample material, is nondestructive, fully reproducible, and does not require any sample preparation procedures. The presented framework can bolster research in the field by cutting down processing time, supporting human-operated microscopy, and further unlocking the paleoclimate potential of ice core records by providing the opportunity to identify an array of ice core particles. Suggestions for an improved system to be deployed within a continuous flow analysis workflow are also presented.Published539-5655A. Ricerche polari e paleoclimaJCR Journa
A MATLAB toolbox for computation of velocity and strain rate field from GNSS coordinate time series
No full textWe propose a MATLAB toolbox for the computation of the strain rate field from the coordinate time series of some continuous GNSS stations. It consists of several functions, also compatible with GNU Octave, implementing the following steps: (i) time series download from a data repository (e.g., the Nevada Geodetic Laboratory database); (ii) calculation of velocities of the selected stations by means of the Maximum Likelihood Estimation (MLE) method implemented in the external package Hector, including modeling of offsets, outliers, noise and periodic components; (iii) (optional) filtering of Common Mode Errors; (iv) calculation of the strain rate field with the modified least squares method, in which a scale factor can be introduced to define the locality of the deformation analysis and, besides uncertainty estimation, a geometric evaluation of the significance of the results is provided; (v) visualization of the results for immediate use and easy interpretation for scientific purposes. The toolbox is divided into two components: the first one, named StaVel, performs the steps (i)-(iii) and the second component, GridStrain, performs the steps (iv) and (v). The potential of the toolbox is demonstrated on a real dataset. Time series from several continuous GNSS stations in South-Eastern Sicily (Southern Italy) are processed by means of StaVel and GridStrain in order to provide the strain rate field.PublishedGD317OST3 Vicino alla fagliaJCR Journa
Comparison analysis of the ETAS model with Gutenberg–Richter (GR), Tapered-GR and characteristic magnitude distributions
No full textThis article has been accepted for publication in Geophysical Journal International ©:The Author(s) 2023. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.Uploaded in accordance with the publisher's self-archiving policy.
All rights reserved.In this paper, we carry out a comparison analysis of the Epidemic Type Aftershock Sequence (ETAS) model for the earthquake process, embedded with the three main exponential-type distributions adopted in practical applications to describe the magnitudes of seismic events, that are, the Gutenberg–Richter (GR), the tapered Gutenberg–Richter (TGR) and the CHaracteristic (CH) frequency–magnitude distributions (FMDs). The first law is a pure-power decreasing function, while both the other two introduce a more rapid decay in the tail of the distribution: a soft taper in the TGR model and a sharp cut-off in the CH one. To perform the comparison, we first investigate some theoretical features of the ETAS model with CH-distributed magnitudes (ETAS-CH), which have not been deeply analysed in the literature as much as for ETAS-TGR and ETAS-GR. In particular, we explicitly compute the branching ratio, we analyse its asymptotics in relation to its parameters, and we derive the proper stability conditions. We then move to the comparison among the three ETAS-GR, ETAS-TGR and ETAS-CH processes, to highlight differences and similarities. This is done by carrying out both a theoretical analysis, mainly focused on the three models’ branching ratios and the relative sensitivity, and a simulation analysis of realistic synthetic catalogues to compare the processes’ numbers, events’ magnitude distribution and temporal evolution. The results we obtained show that the ETAS-TGR and ETAS-CH processes have very similar features. They both have also less restrictive non-explosion conditions than for ETAS-GR; in fact, differently from this latter case, their branching ratios exist for any value of the parameters and are lower than the one of ETAS-GR, to which they converge for large magnitudes.Published413-4285T. Sismologia, geofisica e geologia per l'ingegneria sismicaJCR Journa
Archaeobotanical and Historical Insights on Some Steps of Forest Cover Disruption at Ustica Island (Sicily, Italy) from Prehistory Until Present day
No full textThis paper interprets the first archaeobotanical data to emerge from the island of Ustica (north western Sicily, Italy). The excavation of the Neolithic site of Piano dei Cardoni (4600-4200 cal BC) and the Middle Bronze Age site of Faraglioni Village (1500-1250 cal BC), has made it possible to analyse plant macro-remains and compare them with data on local vegetation obtained from both historical literary sources and recent field surveys. The onset of agro pastoral practices in the mid-5th millennium BC brought about significant changes to the local pristine plant communities. Indeed, the presence of holm oaks and pine trees in that period was recently detected for the first time. The evolution of the local vegetation following the first human settlement in the Neolithic has some crucial parallels with what happened following the recolonisation of the mid-eighteenth century. The massive presence of olive trees during the Middle Bronze Age suggests the deliberate introduction of this crop species on the island and attests to olives’ paramount importance for the local economy at that time. The disappearance of some woody species shows that human occupation has had a powerful impact on the island’s forest resources, which partially recovered during the repeated long phases of land abandonment.Published312-3276SR VULCANI – Servizi e ricerca per la società7SR AMBIENTE – Servizi e ricerca per la societàJCR Journa