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New Insights on Ground Deformation at Campi Flegrei Caldera Inferred From Kinematics and Dynamics Investigation of Borehole Tilt
No full textThe study of the ground deformation in active calderas provides valuable indications of the ongoing dynamical processes. In this framework, we analyze the borehole tiltmeter data recorded at Campi Flegrei (Southern Italy) from their first installation (1 April 2015), in order to retrieve the kinematics of the ground deformation and its main anomalies. Our approach involves the nonlinear dynamics analysis aimed at the identification of the degrees of freedom of the system and thus its complexity. Starting from the second part of the year 2020, the behavior of the dynamical system becomes collective, and a locally significant deviation of the deformative pattern from the background trend is observed. In particular, a series of 15 slow tilt variations (like jumps lasting a few days) appears in the ground deformation. They are associated with a very low-dimensional system likely generated by a local second-order source. The latter is related to fluid migration and it is superimposed on the primary one located in Pozzuoli town and driving the current uplift of Campi Flegrei. The effects of such a local, second-order stress field are, indeed, evident in the area of the volcanic dome of Mt. Olibano, where they are measured as tilt steps. The superposition of primary and second-order sources of deformation acting contemporaneously can justify the recent variations in geophysical and geochemical parameters. Our approach based on the joint dynamical and kinematical analyses of the tiltmeter data can be applied to other volcanic/tectonic areas or extended to other geophysical and geochemical variables.Publishede2022EA0027024V. Processi pre-eruttiviJCR Journa
Extraction and applications of Rayleigh wave ellipticity in polar regions
No full textSeismic Rayleigh wave ellipticity measurements are the horizontal-to-vertical ratio of the Rayleigh wave particle motion, and are sensitive to the subsurface structure beneath a seismic station. H/V ratios measured from the ambient vibrations of the Earth are being increasingly used in glaciological applications to determine glacier and ice sheet thickness, seismic velocities and firn properties. Using the newly developed degree-of-polarisation (DOP-E) method which exploits the polarisation properties of seismic noise, we identify and extract Rayleigh waves from seismic stations in Greenland, and relate them to sea ice processes and the geology of the upper crust. Finally, we provide some suggestions for future applications of DOP-E method to gain greater insight into seasonal and long-term variability of sea ice formation and breakup as well as the monitoring of ice sheet thickness, subglacial environment and firn layers in the poles.Published3-7OST1 Alla ricerca dei Motori GeodinamiciJCR Journa
SAR Data for Detecting Landslide Phenomena: The November 26, 2022 Landslide of the Ischia Island (Southern Italy)
No full textIn this work several change detection techniques based on satellite SAR data acquired by Cosmo-SkyMed Second Generation missions have been evaluated aiming at detecting the landslide-mudflow phenomenon triggered by the strong flooding event that hit Ischia Island in November 2022. It severely impacted on Casamicciola Terme area causing damages and collapses of many buildings and unfortunately also casualties. Experimental results show how both Single- (SP) and Dual- (DP) Polarimetric techniques are able to detect the main landslide occurring along the northern flank of Mt. Epomeo and in some cases also connected phenomena such as mud accumulation. Additional analyses have been performed to quantitatively evaluate the performance of all of them showing as in this case DP techniques outperform the SP ones. The outcomes are then discussed taking into account both the features of each technique and the investigated scenario. Detecting and mapping this kind of phenomena is important for the evaluation of the affected area, especially for complex scenarios such as Ischia island, and can be very useful to support both the stakeholders for the first aid and the Civil Protection for the post-crisis management.Published5686 - 5694OSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa
A New Radar‐Based Statistical Model to Quantify Mass Eruption Rate of Volcanic Plumes
No full textAccurate forecasting of volcanic particle (tephra) dispersal and fallout requires a reliable
estimation of key Eruption Source Parameters (ESPs) such as the Mass Eruption Rate (Q M). QM is usually
estimated from the Top Plume Height (HTP) using empirical and analytical models. For the first time, we
combine estimates of HTP and QM derived from the same sensor (radar) with mean wind velocity values (vW) for
lava-fountain fed tephra plumes associated with 32 paroxysms of Mt. Etna (Italy) to develop a new statistical
model based on a Markov Chain Monte Carlo approach for model parameter estimation. This model is
especially designed for application to radar data to quickly infer QM from observed HTP and vW, and estimate the
associated uncertainty. It can be easily applied and adjusted to data retrieved by radars worldwide, improving
our capacity to quickly estimate QM and related uncertainties required for the tephra dispersal hazard.Publishede2022GL1005965V. Processi eruttivi e post-eruttiviJCR Journa
Geophysical and Geochemical Exploration of the Pockmark Field in the Gulf of Patras: New Insights on Formation, Growth and Activity
No full textThe Patras Gulf Pockmark field is located in shallow waters offshore Patras City (Greece) and is considered one of the most spectacular and best-documented fluid seepage activities in the Ionian Sea. The field has been under investigation since 1996, though surveying was partially sparse and fragmentary. This paper provides a complete mapping of the field and generates new knowledge regarding the fluid escape structures, the fluid pathways, their origin and the link with seismic activity. For this, data sets were acquired utilising high-resolution marine remote sensing techniques, including multibeam echosounders, side-scan sonars, sub-bottom profilers and remotely operated vehicles, and laboratory techniques focusing on the chemical composition of the escaping fluids. The examined morphometric parameters and spatial distribution patterns of the pockmarks are directly linked to tectonic structures. Acoustic anomalies related to the presence of gas in sediments and in the water column document the activity of the field at present and in the past. Methane is the main component of the fluids and is of microbial origin. Regional and local tectonism, together with the Holocene sedimentary deposits, appear to be the main contributors to the growth of the field. The field preserves evidence that earthquake activity prompts the activation of the field.Published10449OSA4: Ambiente marino, fascia costiera ed Oceanografia operativaJCR Journa
Editorial: From preparation to faulting: multidisciplinary investigations on earthquake processes
No full textIn seismically active areas (e.g., Han et al., 2022), the best way for disaster mitigation is to
enhance the skills of risk evaluation and prediction (Shao et al., 2023). What happens before an
earthquake occurs? Which are the physical processes that take place in the Earth’s crust before the
earthquake nucleates? How can we observe, describe, and model them statistically, numerically,
and physically in multi-scales from laboratory samples to tectonic earth plates? Those questions are
fundamental but have not been completely solved (Geller, 1997; Pritchard, et al., 2020).
Over the last few decades multidisciplinary studies have attempted to answer these
fundamental questions (e.g., King, 1978; Ma, 1987; Kanamori and Brodsky, 2001). In the
early days, the Institute Physics of the Earth (IPE) model (dry) (Myachkin et al., 1975) and
the Dilatance Diffusion (DD) model (wet) (Scholz et al., 1973) were proposed for earthquake
processes. Like Schrödinger’s cat, an earthquake is unpredictable—according to the IPE
model, yet it can be predictable—according to the DD model (Ma, 1987). Recently, with
advanced techniques, some scientists have discovered the meta-instable stage before failure
to slip (Ma et al., 2012) and assuredly claimed that there are precursors to be used for
earthquake forecasting (Ma, 2016), which envisages new opportunities to study earthquake
precursors (Pritchard, et al., 2020).
An understanding of the governing laws (e.g., King, 1978; Zöller et al., 2010; Shi et al.,
2020; Chen et al., 2022), from long-term tectonic loading (Zhang et al., 2022) and nucleation to rapid rupture propagation (Yang et al., 2022), is significant to
earthquake forecasting and demands a comprehension of the stress
state and evolution during the time of geophysical observations
around seismically active areas (Zhao et al., 2020; Zhao et al., 2022).
The evidence from multiscale experiments (Ma and Guo, 2014;
Huang et al., 2019; Huang et al., 2020; Martinelli et al., 2020),
multidisciplinary monitoring system networks (Huang FQ. et al.,
2017; Martinelli et al., 2021), numerical modeling (Barbot et al.,
2012; Huang FQ. et al., 2017; Ben-Zion, 2017), and field
investigations (e.g., King, 1978), are the keys to advance our
understanding of earthquake mechanics.
Earthquakes do not occur everywhere. Fault geometry and the
physical properties of fault zones (namely, seismogenic structure),
geological and tectonic settings (Wang et al., 2014; Dascher-
Cousineau et al., 2020; Gong et al., 2020), as well as crustal
movement and the geodynamic environment, play pivotal roles
in the seismic patterns (e.g., King, 1978; Ikeda, 2009; Luo et al.,
2023). A variety of geophysical and geochemical observations,
ranging from ground-related deformation patterns (GPS, SAR,
etc.) (Bürgmann et al., 2000; Zhao et al., 2020) to pre-earthquake
changes (geochemical, electromagnetic, hydro-geological, geodetic,
or thermodynamic) (Huang F. Q. et al., 2017; Zhou et al., 2020; Chen
et al., 2021; Martinelli et al., 2021; Zhou et al., 2021), recorded by
ground-based (Li et al., 2022) or satellite-based techniques (Li et al.,
2020) may be related to stress variations in the lithosphere (Luo
et al., 2023) prior to an eventual large earthquake (Zhao et al., 2022).
Even though much effort has been invested, the earthquake
“elephant in the room” is still in the process of being understood.
This Research Topic aims to provide state-of-the-art studies
on earthquake processes via multidisciplinary approaches from
geophysical, geochemical, geodetical, and geological routines
which are mostly exchanged at the annual conference of the
China Earthquake Prediction Forum (Huang et al., 2023). Preearthquake
observations, methods, and perspectives, can
provide a current view in the knowledge of processes
preceding earthquake occurrence in China, which can be
possibly employed to set up earthquake forecasting
experiments, aimed at their verification Test Site areas,
whether large or small.
2 Overview on published contributions
There are eleven articles collected for this Research Topic,
involving precursors of monitoring networks and earthquake
prediction methods (four articles), stress state of the geodynamic
environment inferred from recent earthquakes (two articles),
seismogenic structure and fault geometry from deep to surface
(four articles) and models for earthquake risk assessment of the
National Test site (one article).
2.1 Precursors of monitoring networks and
earthquake prediction method
Extracting anomalous changes relevant to earthquake
processes from observation systems is the key step to routine
earthquake prediction. Here we have collected one article based
on laboratory work that involves judging rock instability by
enhanced LURR (short-term to imminent before “earthquakes,”
by Zhang et al., The evolution characteristics of rock fracture
instability under cyclic loading on the basis of the enhanced
LURR), and three articles involving the extraction of
anomalous changes before strong earthquakes on the China
Mainland from seismograph observation systems from the
long-term to the short-term stage. Frequency field (Luo et al.,
Pre-quake frequency characteristics of Ms ≥7.0 earthquakes in
mainland China), b-value (Bi et al., Strong aftershocks traffic
light system: A case study of the 8 January 2022 MS6.9 Menyuan
earthquake, Qinghai Province, China) and anomalous quiet or
enhanced processes of small to moderate earthquakes before the
strong earthquakes (Gao et al., Low-intensity anomaly involving
ML≥4 events preceding strong earthquakes in Tibet) are the main
items to be discussed.Published1220232JCR Journa
Robinia pseudoacacia L. (Black Locust) Leaflets as Biomonitors of Airborne Microplastics
No full textHere we investigate the suitability of Robinia pseudoacacia L. (black locust) leaflets as a novel biomonitor of airborne microplastics (MPs) including tyre wear particles (TWPs). Leaflets were collected from rural roadside locations (ROs, n = 5) and urban parks (UPs, n = 5) in Siena, Italy. MPs were removed by washing, identified by stereomicroscope, and analysed for polymer type by Fourier transform infrared spectroscopy. Daily MP deposition was estimated from leaf area. The mass magnetic susceptibility and the bioaccumulation of traffic-related potentially toxic elements (PTEs) were also analysed. The total number of MPs at ROs was significantly higher at 2962, dominated by TWPs, compared with 193 in UPs, where TWPs were not found. In contrast, total microfibres were significantly higher in UPs compared with ROs (185 vs. 86). Daily MP deposition was estimated to range from 4.2 to 5.1 MPs/m2/d across UPs and 29.9–457.6 MPs/m2/d across ROs. The polymer types at ROs were dominated by rubber (80%) from TWPs, followed by 15% polyamide (PA) and 5% polysulfone (PES), while in UPs the proportion of PES (44%) was higher than PA (22%) and polyacrylonitrile (11%). The mean mass magnetic susceptibility, a proxy of the bioaccumulation of traffic-related metallic particles, was higher at ROs (0.62 ± 0.01 10–8 m3/kg) than at UPs (–0.50 ± 0.03 10–8 m3/kg). The content of PTEs was similar across sites, except for significantly higher concentrations of Sb, a tracer of vehicle brake wear, at ROs (0.308 ± 0.008 µg/g) compared with UPs (0.054 ± 0.006 µg/g). Our results suggest that the waxy leaflets and easy determination of surface area make Robinia an effective biomonitor for airborne MPs including TWPs.this work was partially supported by the INGV project Pianeta Dinamico CHIOMA (CUP D53J19000170001) funded by MUR (Ministry of University and Research).Published1456OSA1: Variazioni del campo magnetico terrestre, imaging crostale e sicurezza del territorioJCR Journa
In the wake of a big quake
No full textThe 18th-century European press network functioned in a non-linear way: newspapers tended to publish news from far-off countries rather than those of merely local interest. Thus, some Italian news may be only reported in non-Italian gazettes, or Italian gazettes omit to report some interesting details that reach instead – via the underground network of handwritten reports and diplomatic correspondence – some foreign gazettes. On the other hand, however, exaggerations or outright hoaxes are frequent both in Italian and non-Italian gazettes.
In order to understand how journalistic communication functioned and how the traces of some earthquakes were collected and preserved by seismological compilations, we examined the output of several Italian and European gazettes in the months after the great Lisbon earthquake of 1 November 1755.
During this period the European press network overflows with reports of the effects of the “big one” in Portugal and abroad, and also publish a spate of news of other earthquakes in Europe and the Mediterranean area. Some - the 9 December 1755 Valais earthquake, the 13 February 1756 Rhodos, and the 18 February Düren earthquakes - were real enough and quite strong too. Others were minor or - in some cases - even wholly fictitious events. Our survey discovers the traces of a few earthquakes still unknown to the current parametric catalogues and allows us to reevaluate an earthquake that turns out to represent the historical maximum for the city of Treviso (Veneto, Italy).UnpublishedBerlinOST1 Alla ricerca dei Motori Geodinamic
An overview of sedimentary volcanism on Mars
No full textExtensive fields of sub-kilometre- to kilometre-scale mounds, cones, domes, shields, and flow-like edifices cover large parts of the martian lowlands. These features have been compared to structures on Earth produced by sedimentary volcanism – a process that involves subsurface sediment/fluid mobilisation and commonly releases methane to the atmosphere. It was proposed that such processes might help to explain the presence of methane in the martian atmosphere and may also have produced habitable, subsurface settings of potential astrobiological relevance. However, it remains unclear if sedimentary volcanism on Earth and Mars share genetic similarities and hence if methane or other gases were released on Mars during this process. The aim of this review is to summarise the current knowledge about mud-volcano-like structures on Mars, address the critical aspects of this process, identify key open questions, and point to areas where further research is needed to understand this phenomenon and its importance for the Red Planet's geological evolution. We show here that after several decades of exploration, the amount of evidence supporting martian sedimentary volcanism has increased significantly, but as the critical ground truth is still lacking, alternative explanations cannot be ruled out. We also highlight that the lower gravity and temperatures on Mars compared to Earth control the dynamics of clastic eruptions and surface emplacement mechanisms and the resulting morphologies of erupted material. This implies that shapes and triggering mechanisms of mud-volcano-like structures may be different from those observed on Earth. Therefore, comparative studies should be done with caution. To provide a better understanding of the significance of these abundant features on Mars, we argue for follow-up studies targeting putative sedimentary volcanic features identified on the planet's surface and, if possible, for in situ investigations by landed missions such as that by the Zhurong rover.Published633–661OSA5: Energia e georisorseJCR Journa
Digital Twins Components for Geophysical Extreme Phenomena: the example of Vlcanic Hzards within the DT-GEO projec
No full textThe project Digital Twin for GEOphysical extremes-(DT-GEO) aims to use Digital Twin Components to create replicas of physical systems, serving as a virtual laboratory to study natural extreme events. The ratio- nale is the intrinsic risks of potentially catastrophic events to anthropic activities, infrastructures, and cultural heritage. In the framework of the project, this paper describes, how the DTC workflow architecture is designed, focusing on flexibility, scalability, and maintainability, and how it is further developed. To demonstrate how ICT efforts can expand horizons in Geosciences, an application to volcanic hazard is presented taking as a case study the 2019 volcanic eruption of Raikoke (Kuril Islands).Published8-16OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciN/A or not JC