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A multi-step approach to evaluate the sustainable use of groundwater resources for human consumption and agriculture
No full textThe rapid decline in both quality and availability of freshwater resources on our planet necessitates their thorough assessment to ensure sustainable usage. The growing demand for water in industrial, agricultural, and domestic sectors poses significant challenges to managing both surface and groundwater resources. This study tests and proposes a hybrid evaluation approach to determine Groundwater Quality Indices (GQIs) for irrigation (IRRI), seawater intrusion (SWI), and potability (POT), finalized to the spatial distribution of groundwater suitability involving water quality indicator along with hydrogeological and socio-economic factors. Mean Decrease Accuracy (MDA) and Information Gain Ratio (IGR) were used to state the importance of chosen factors such as level of groundwater above the sea, thickness of the aquifer, land cover, distance from coastline, silt soil content, recharge, distance from river and lagoons, depth to water table from ground, distance from agricultural wells, hydraulic conductivity, and lithology for each quality index, separately. The results of both methods showed that recharge is the most important parameter for GQIIRRI and GQIPOT, while the distance from the coastline and the rivers, are the most important for GQISWI. The spatial modelling of GQIIRRI and GQIPOT in the study area has been achieved applying three machine learning (ML) algorithms: the Boosted Regression Tree (BRT), the Random Forest (RF), and the Support Vector Machine (SVM). Validation results showed that RF has the highest prediction for GQIIRRI, while the SVM model has the highest prediction for the GQIPOT index. It is worth to mention that the future utilization and testing of new algorithms could produce even better results. Finally, GQIIRRI and GQIPOT were combined and compared using two combine and overlay methods to prepare a hybrid map of multi-GQIs. The results showed that 69% of the study area is suitable for irrigation and potable use, due to both geogenic and anthropogenic activities which contribute to make some water resources unsuitable for either use. Specifically, the northern, western, and eastern portions of the study area are in the "very high and high quality" classes while the southern portion shows "very low and low quality" classes. In conclusion, the developed map and approach can serve as a practical guide for enhancing groundwater management, identifying suitable areas for various uses and pinpointing regions requiring improved management practices.Published119041JCR Journa
Multidisciplinary Study of Mud Emissions Following the 2016 Norcia Earthquake
No full textWe report composition, grain size, and rheological data related to the mud emitted as a consequence of the maximum moment magnitude (Mw max = 6.5) on 30 October 2016, commonly referred to as the Norcia earthquake (central Italy), and on the activity of pre-existent mud volcanoes affected by the central Italy seismic sequence started on 24 August 2016. The emission sites were located at Monteleone di Fermo and Santa Vittoria in Matenano, two municipalities near the town of Fermo (Marche Region, Italy). We sampled, measured, and analyzed the products of mud emissions 3 days after the mainshock to characterize the mud by geochemical, mineralogical, and rheological analyses. The muds’ geochemical composition and low electrical conductivity suggest a continental origin, likely belonging to the Colombacci Formation. The collected muds are silt–sand–water-rich suspensions characterized by a Bigham rheology with viscosity values between 6.3∙107 and 6.9∙105 Pa∙s. The calculated minimum fluidization velocity of the mud suspensions is between 0.05 m/s (grain size of 2 μm) and 0.74 m/s (grain size of 8 μm). Water-rich mud suspensions flowing on a slope move faster as the water content increases up to 30 wt.%. At higher values, the velocity remains almost constant due to the disaggregation of bonds among the solid particles in the mixtures.Published69681T. Struttura della TerraJCR Journa
Gravity modelling of the Tyrrhenian-Calabrian-Ionian subduction system
No full textThis study provides a lithospheric-scale model along the Ionian Subduction zone
in Southern Italy, contributing to the seismotectonic investigation of a region
which is affected by relevant historical seismicity. The study employs gravity
forward modelling to build the geo-structural model along a composite, NWSE
trending transect extending from the Ionian to the Tyrrhenian Sea, including the
Aeolian arc and the Calabro-Peloritan onshore. Through a multidisciplinary
approach, we propose new interpretations of three 2D deep-seismic reflection
profiles across the study area. Such interpretative profiles are used as constraints
to model the observed Bouguer gravity anomalies providing upper and lower crust
geometries. Whilst a tomographic model provides constraints for the lithospheric
and asthenospheric modelling. The entire workflow is constrained by literature
data about Moho geometry, deep seismicity and tomographic images that are
integrated to determine the subducting slab geometry. The proposed model of
the entire subducting system reasonably fits the observed gravity field and is
coherent with the first-order geological and geophysical constraints. The
modelling results in updated Tyrrhenian and Ionian Moho depth, subducting
slab geometry and location, and densities of the main units, providing valuable
input about the composition and geometry of the Calabrian arc structures.PRIN-2017 (project #2017KT2MKE_003)Published1259831OST1 Alla ricerca dei Motori GeodinamiciJCR Journa
A new accurate retrieval algorithm of bromine monoxide columns inside minor volcanic plumes from Sentinel-5P TROPOMI observations
No full textBromine monoxide (BrO) is a key radical in the atmosphere, influencing the chemical state of the atmosphere, most notably the abundance of ozone (O3). O3 depletion caused by the release of bromine has been observed and modeled in polar regions, salt pans, and in particular inside volcanic plumes. Furthermore, the molar ratio of BrO and SO2 – which can be detected simultaneously via spectroscopic measurements using the differential optical absorption spectroscopy (DOAS) method – is a proxy for the magmatic composition of a volcano and potentially an eruption forecast parameter.
The detection of BrO in volcanic plumes from satellite spectroscopic observations is limited by the precision and sensitivity of the retrieval, which so far only allowed for the detection of BrO during major eruptions. The unprecedented spatial resolution of up to 3.5 km×5.5 km and the high signal-to-noise ratio of the TROPOspheric Monitoring Instrument (TROPOMI) on board Sentinel-5 Precursor (S-5P) enable observing and monitoring volcanic bromine release globally even for minor eruptions or even quiescent degassing.
In this study, we investigate how far the BrO retrieval can be improved using TROPOMI data and how well BrO can be detected, even in small eruptions and during quiescent volcanic degassing. There are two steps for which improvements in accuracy are investigated and applied: the improvement and quantitative determination of (1) the detection limit of the DOAS BrO column retrieval and (2) the correction of the non-volcanic background BrO signal. First, the DOAS retrieval settings are varied, and their influence on accuracy and precision is investigated with respect to the detection limit and potential systematic influences. Based on these results, we propose a dedicated DOAS evaluation scheme optimized for the detection of BrO in volcanic plumes. For the DOAS retrieval, we propose the use of a large fit window from 323–360 nm, yielding a statistical uncertainty lower by a factor of 1.8 compared to previous BrO DOAS algorithms while not enhancing systematic influences. Second, the effect of the background BrO is reduced by a latitude-dependent empirical correction scheme correlated to cloud information as well as information on the O3 column. Via these improvements, the combined statistical and systematic uncertainties in the resulting BrO vertical column density is on the order of .
We present a new and accurate retrieval algorithm of BrO columns from TROPOMI observations which allows for the detection of even slightly enhanced BrO amounts inside minor eruptive plumes of bromine-rich volcanoes. While designed specifically for TROPOMI observations, the retrieval algorithm is in general also applicable to other hyperspectral satellite observations. However, some parts might require adaptation.Published5537–5573OSV3: Sviluppo di nuovi sistemi osservazionali e di analisi ad alta sensibilitàJCR Journa
Archaeometric Characterisation and Assessment of Conservation State of Coins: The Case-Study of a Selection of Antoniniani from the Hoard of Cumae (Campania Region, Southern Italy)
No full textThe paper presents the first archaeometric results on a selection of ancient Roman coins (antoniniani) from a treasure found in the Roman necropolis area of ancient Cumae (Southern Italy) during archaeological campaigns by the Centre Jean Bérard. A multi-analytical approach consisting of non-destructive techniques (stereomicroscopy, FESEM-EDS, pXRF, Raman, μ-CT) was implemented on the better-preserved coins of the treasure in order to investigate the chemical composition of the alloy. Chemical analysis showed that the Roman mint prepared the metal with an argentiferous lead–bronze alloy. A group of coins presents a low content of the precious metal, which is in agreement with the financial crisis of the Roman Empire of the third century. Another group of two coins shows a higher silver content, which is in agreement with their issue or with the Mediolanum mint standards. In addition, the external layers of corroded coins were analysed to explore the state of conservation of the patina and to identify the corrosion products. Some typical corrosion patinas due to post-depositional conditions were identified. The mineralogical characterisation of the corrosion products enables us to implement adequate conservation strategies, and the presence of more aggressive patinas suggests immediate interventions.Published2038–2055JCR Journa
SISMIKO: INGV operational task force for rapid deployment of seismic network during earthquake emergencies
No full textThe National Institute of Geophysics and Volcanology (INGV, Istituto Nazionale di Geofisica e Vulcanologia), is an italian public research institute established in 1999. Since its inception, the mission of INGV included seismic surveillance and earthquake monitoring in Italy. INGV is part of the Civil Defence system (Margheriti et al., 2021). INGV has offices in different parts of Italy and operates the Italian National Seismic Network (Rete Sismica Nazionale—RSN; INGV Seismological Data Centre, 2006) and other networks at national scale (Michelini et al., 2017). INGV also operates a temporary seismic network infrastructure, a pool of instruments used to densify seismic networks for scientific experiments or in response to damaging earthquakes and to increase monitoring capabilities during seismic sequences.
SISMIKO is the operational task force of INGV whose core purpose is to rapidly deploy temporary seismic stations in response to moderate—large magnitude earthquakes or in areas where a seismic sequence is causing concerns and/or scientific interest (Moretti et al., 2016). By reducing the spatial distance between the seismic stations, temporary deployments can improve the RSN detection capability and the accuracy of the earthquake locations. SISMIKO was established in 2015 by Lucia Margheriti and Milena Moretti, so they became responsible for INGV emergency deployments of the temporary networks. SISMIKO involves INGV technicians and researchers from all over Italy, from Milano to Catania (see acknowledgments), grouped together by common interest technical and scientific issues. SISMIKO coordinates all INGV groups working on seismic emergencies (Figure 1).
The data acquired by the SISMIKO temporary networks, are made available to the scientific community, without any restrictions, via italian node of the European Integrated Data Archive portal (EIDA1; Danecek et al., 2021). Datasets are archived in near real-time in the “Standard for the Exchange of Earthquake Data (SEED)” format and have an associated Digital Object Identifier (DOI). The data are used for monitoring, surveillance and for scientific research.
Since its establishment, SISMIKO has installed seven temporary seismic networks, including the one used to monitor the 2016–2018 seismic sequence in central Italy (Moretti et al., 2016). The most recent activations of SISMIKO were in May and November 2022: Chianti-Fiorentino (Piccinini et al., 2022; 2023) and North Marche coast (D’Alema et al., 2022b), respectively.
The following section briefly describes the history of the INGV emergency mobile network.Published1146579OST5 Verso un nuovo MonitoraggioJCR Journa
The earthquake of September 1924 in the Ligurian Sea and its relationship with the recent seismic event in Bargagli (Genoa, Italy, September 2022)
No full textOn September 22, 2022 the Bargagli area, located about 10 kilometers away from Genoa, was
affected by a series of earthquakes of which the largest was that of 15.39 (local time), of magnitude
Mw 4.0. The event was felt in a very large area and caused minor damage to a church and a cemetery.
A few smaller magnitude tremors followed, mainly clustered in the first few days after the main event.
The peculiarity of this seismic crisis is that it occurred in an area not previously affected by earthquakes
of that magnitude, at least according to the information contained in the historical and instrumental
catalogs currently available. This article describes a study carried out using instrumental bulletins and
historical seismograms stored in the Sismos project database to study in greater detail the seismicity
of the area and provide any information on other earthquakes that occurred in that sector of the
Ligurian Apennines. Based on the results obtained, we propose that the earthquake of September 21,
1924, originally located offshore about two kilometers from the Ligurian coast, actually took place in
the vicinity of Bargagli. Although this new position has no particular implications for the seismic hazard
of the area, however, it represents an important information to be taken into account in the
calculation of the return period and in the seismotectonic interpretation of the area.Published3-244T. Sismicità dell'ItaliaJCR Journa
From ambient vibration data analysis to 1D ground-motion prediction of the Mj 5.9 and the Mj 6.5 Kumamoto earthquakes in the Kumamoto alluvial plain, Japan
No full textWe present horizontal ground motion predictions at a soft site in the Kumamoto alluvial plain for the Mj 5.9 and Mj 6.5 Kumamoto earthquakes of April 2016, in the framework of an international blind prediction exercise. Such predictions were obtained by leveraging all available information which included: (i) analysis of earthquake ground motions; (ii) processing of ambient vibration data (AMV); and (iii) 1D ground response analysis. Spectral analysis of earthquake ground-motion data were used to obtain empirical estimates of the prediction site amplification function, with evidence of an amplification peak at about 1.2 Hz. Horizontal-to-vertical spectral ratio analysis of AMV confirmed this resonance frequency and pointed out also a low-frequency resonance around 0.3 Hz at the prediction site. AMV were then processed by cross-correlation, modified spatial autocorrelation and high-resolution beamforming methods to retrieve the 1D shear-wave velocity (Vs) structure at the prediction site by joint inversion of surface-wave dispersion and ellipticity curves. The use of low frequency dispersion curve and ellipticity data allowed to retrieve a reference Vs profile down to few thousand meters depth which was then used to perform 1D equivalent-linear simulations of the M 5.9 event, and both equivalent-linear and nonlinear simulations of the M 6.5 event at the target site. Adopting quantitative goodness-of-fit metrics based on time–frequency representation of the signals, we obtained fair-to-good agreement between 1D predictions and observations for the Mj 6.5 earthquake and a poor agreement for the Mj 5.9 earthquake. In terms of acceleration response spectra, while ground-motion overpredictions were obtained for the Mj 5.9 event, simulated ground motions for the Mj 6.5 earthquake severely underestimate the observations, especially those obtained by the nonlinear approach.stituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy.Published105OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impattoJCR Journa
Fluid-mineral dynamics at the Rincón de la Vieja volcano—hydrothermal system (Costa Rica) inferred by the study of major, minor and rare earth elements in the hyperacid crater lake
No full textVolcanic lakes are complex natural systems and their chemical composition is
related to a myriad of processes. The chemical composition of major, minor, Rare
Earth Elements (REE) and physico-chemical parameters at the hyperacid crater
lake of Rincón de la Vieja volcano (Costa Rica) are here investigated during
February 2013–August 2014. The study of the lake chemical composition
allows to identify the main geochemical processes occurring in the lake and to
track the changes in the volcanic activity, both important for active volcanoes
monitoring. The total REE concentration ( REE) dissolved in the crater lake varies
from 2.7 to 3.6 mg kg−1 during the period of observation. REE in the water lake
samples normalized to the average volcanic local rock (REEN-local rock) are
depleted in light REE (LREE). On the contrary REEN-local rock in the solids
precipitated (mainly gypsum/anhydrite), from lake water samples in laboratory
at 22°C, are enriched in LREE. The low variability of (La/Pr)N-local rock and (LREE/
HREE)N-local rock ratios (0.92–1.07 and 0.66–0.81, respectively) in crater lake
waters is consistent with the low phreatic activity (less than 10 phreatic
eruptions in 2 years) observed during the period of observation. This period of
low activity precedes the unrest started in 2015, thus, it could be considered as a
pre-unrest, characterized by infrequent phreatic eruptions. No clear changes in
the REE chemistry are associated with the phreatic eruption occurred at mid-
2013. The results obtained investigating water-rock interaction processes at theRincón de la Vieja crater lake show that rock dissolution and mineral precipitation/
dissolution are the main processes that control the variability of cations
composition over time. In particular, precipitation and dissolution of gypsum
and alunite are responsible for the variations of REE in the waters. Despite the
low variations of (La/Pr)N-local rock and (LREE/HREE)N-local rock ratios, this study
allows to suggest that REE can be used, together with major elements, as
practical tracers of water-rock interaction processes and mineral precipitation/
dissolution at active hyperacid crater lakes over time, also during periods of
quiescence and low phreatic activity.Published1197568OSV3: Sviluppo di nuovi sistemi osservazionali e di analisi ad alta sensibilitàJCR Journa
Implications for the geometry of plate boundaries in NE Asia based on the geodetic analysis of the 2020Mw 6.4 Koryak event
No full textOn the 9th of January 2020, an Mw 6.4 strike-slip earthquake took place north of the Asian
margin of the Bering Sea. The earthquake occurred within the known reverse-right-lateral
active fault zone, called Khatyrka–Vyvenka, which transverses the Koryak Highland from
SE to NW and is thought to be a surface manifestation of the Asian portion of either the
Bering plate boundary or the northern edge of the Alaskan stream. No other strong earthquake
has ever been recorded in this remote uninhabited area and the few existing seismic stations
provide poor quality earthquake locations.We adopt SAR interferometry (InSAR) technique to
define an improved location of the Koryak 2020 earthquake and constrain the seismic source.
The analysis of the 2020 event revealed a previously unknown active fault of left-lateral
kinematics that is possibly hidden and strikes NWtransversely to the Khatyrka–Vyvenka fault
zone. Although several mechanisms could account for left-lateral kinematics of this fault,
we propose that the structure is part of a more extended NW fault structure, that formed in
pre-neotectonic times and has played a role of a pre-existing rheological discontinuity. This
revived NW structure together with a similar structure located easterly, so far aseismic, make
the plate/stream boundary segmented, step-like in plan view. The step-like boundary geometry
may be the result of internal transform deformation of a rigid plate, but it is better explained
by deflections of the Alaskan stream edge at local crustal asperities, which are pre-Cenozoic
terrains.Published1412–1421OST2 Deformazione e Hazard sismico e da maremotoJCR Journa