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Paleomagnetic Evidence for Pre‐21 Ma Independent Drift of South Sardinia From North Sardinia‐Corsica: “Greater Iberia” Versus Europe
No full textIt is unanimously acknowledged that the Corsica-Sardinia microplate rotated counterclockwise (CCW) by 40–50° between 21 and 15 Ma, synchronous with Liguro-Provençal Basin oceanic spreading. Conversely, 60–120° CCW rotations with respect to Europe from Sardinia (Permian dykes, volcanics and sediments, Mesozoic carbonates, and lower Eocene limestones) have been interpreted to be related to (a) late Permian intra-Pangea shear events, (b) Aptian Iberia rotation, and (c) Eocene Valais Ocean closure. We report paleomagnetic data from 31 red-bed sites from the mid-late Eocene (45–32 Ma) Cixerri Fm. exposed in SW Sardinia. Characteristic paleomagnetic directions from 25 dual polarity sites (240 samples) define an 86 ± 7° CCW rotation. We suggest that a S Sardinia block located NE of Balearic Islands rotated 30° CCW during the 30–21 Ma Liguro-Provençal rifting, and was decoupled from N Sardinia along the left-lateral Nuoro fault. After 21 Ma, Corsica-Sardinia underwent a drift-related 60° CCW rotation as a whole. A re-analysis of available paleomagnetic results shows that Permian data from N Sardinia-Corsica align with European directions considering a 60° CCW rotation, whereas Permian and mid Jurassic data from S Sardinia match European directions only after considering a ∼35° CCW Iberia rotation besides the 90° post-Eocene event. We suggest that S Sardinia was part of Iberia, and rotated CCW during both Aptian Iberia drift and Oligo-Miocene Liguro-Provençal opening. Our data, along with recent paleomagnetic results from Calabria, suggest that S Sardinia, Balearic Islands, Calabria, Peloritan, Kabylies, and Alboran were fragments of “Greater Iberia,” joined to Iberia before 30 Ma Liguro-Provençal rifting.Publishede2022TC0077051A. Geomagnetismo e PaleomagnetismoJCR Journa
High-resolution magnetochronology detects multiple stages of Pleistocene tectonic uplift and deformation in the Po Plain of northern Italy
No full textWe developed a high-resolution magnetochronology of the Pleistocene stratigraphy of the Monte Netto hillock, a tectonically uplifted struc ture in the Po Plain of northern Italy. Our data allowed reconstructing the depositional age of the sequence and assessing rates of defor mation and rock uplift of the neotectonic structure, thus providing constraints on the tectono-sedimentary evolution of this seismically
active part of the buried Southern Alps. Using a combination of magnetostratigraphy and paleosecular variation analysis, we generated
an age-depth model for the Monte Netto stratigraphy that encompasses, from the top, Upper Pleistocene (11–72 ka) loess-paleosols over laying fluvial sediments spanning the Brunhes-Matuyama boundary (773 ka) and the top of the Jaramillo (990 ka). The identification of the
same magneto-chronostratigraphic surfaces in nearby drill cores from regions of the Po Plain that have not been affected by neotectonic
deformation allowed estimating a mean rate of tectonic uplift of the hillock relative to the neighboring plain of 11.3 ± 1.5 cm/ka, and
an absolute uplift relative to sea level of ∼19.3 cm/ka. Finally, our paleomagnetic analyses from the uppermost loess sequence disclosed
the complexity of the tectonic evolution of the Monte Netto structure, which shows evidence of a two-phase rotational deformation linked
to coseismic surface faulting due to recent seismic activity.Published191-205JCR Journa
EPOS-DCAT-AP 2.0 – State of Play on the Application Profile for Metadata Exchange in the EPOS RI
No full textMetadata application profiles are widely employed to enable the exchange of metadata between different systems or platforms.
DCAT-AP is an application profile of the W3C Data Catalog Vocabulary (DCAT) used as a cross-domain and cross-platform metadata interchange format for data catalogues operated in the European Union. Several extensions of DCAT-AP have been created to address domain-specific requirements. Due to the inherent evolving nature of Research Infrastructures, maintenance and regular updates of such profiles are necessary activities in order to assess the matching with existing and new community requirements.
In this paper, we give an overview of the new release of the EPOS-DCAT Application Profile based on DCAT-AP v2.1.0. EPOS-DCAT-AP has been developed, maintained, and adopted by the European Plate Observing System (EPOS) Research Infrastructure to capture the heterogeneity of the assets provided by diverse scientific communities and to increase findability, accessibility, and usability of multidisciplinary data.
EPOS-DCAT-AP is the result of a collaborative ongoing effort of various expertise. This application profile addresses several requirements, and it is suitable for a wide range of applications therefore it can be adopted by other Research Infrastructures.Published248-258OST5 Verso un nuovo Monitoraggi
Provenance and deposition of a lithified volcanic-rich layer (VRL-5.5) at 5.5 Ma from Central Apennines (Italy)
No full textTwo slightly lithified volcanic rich layers (VRL) (former tephra) SVT-2 (San Vittorino) and CAC (Castiglione a Casauria) were sampled from two distinct post-evaporitic Messinian stratigraphic sections (Abruzzo, Central Italy). They crop only few tens of km apart and are predominantly massive, although some specimens show sedimentary structures. Both VRLs were investigated for the first time by field, mesoscopic, X-ray powder diffraction (XRPD), transmission optical microscopy (TOM), scanning electron microscopy (SEM), bulk composition, electron-microprobe analysis (EMPA) and quantitative textural attributes by image analysis. The XRPD analysis detects the presence of a glass phase, plus few (< 2 area %) magmatic-like feldspars, clinopyroxene and biotite and stratigraphically variable sedimentary minerals such as calcite, dolomite, illite and montmorillonite (from 0 to 40 area %). The 2D image analysis performed on SEM microphotographs reveals that both sections are composed of very fine glass shards, magmatic minerals are never isolated, whilst the carbonate crystals mainly fill voids among volcanic particles. Both these VRLs have identical rhyolitic glass compositions that closely overlap with those of previously-studied coeval and stratigraphically related sections occurring in the northern Apennine region and dated as 5.5 Ma. The 2D textural features of glassy particles (length, width, aspect ratio, grain-size distribution, MZ , σi, SKi, KG and roundness) in both SVT-2 and CAC sections are very similar and also close to the northern section of Camporotondo (Marche region). The outcomes provided here indicate that SVT-2 and CAC sections represent the southernmost distal deposits of the same large eruption that occurred about 5.5 Ma (VRL-5.5). They result from distal fallout of tephra through seawater, occasionally remobilised under low energy and localised conditions, especially in the uppermost part of the CAC section. All the VRL-5.5 rocks are probably related to a very large eruption that occurred in the Carpathian-Pannonian magmatic district. The analytical protocols used in this study can be useful to investigate other ancient volcanic-rich layers, corresponding to lithified tephra.Published6880OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
Editorial: Management and monitoring of natural disasters using remote sensing and ground-based data
No full textEditorial on the Research Topic
Management and monitoring of natural disasters using remote sensing and
ground-based dataPublished1323627OST5 Verso un nuovo MonitoraggioJCR Journa
Earthquake Early Warning system: case of the 2022 Marche sequence
No full textIn recent years, the implementation of an early warning system (Earthquake Early Warning, EEW) has become widespread in many countries of the world and in some cases they have been made operational. The study of the vulnerability of urban areas in relation to seismic events has led to the development of different approaches, methodologies and combinations of new experiences. All these systems have in common the purpose of providing rapid notification of the potential harmful effects of a seismic event through the processing of data from monitoring networks in the areas where the source of the event is located or in the areas surrounding the selected targets. Furthermore, the systems, in general, have the purpose of detecting, locating and estimating the magnitude and the shaking parameters of an event starting from the analysis of a few seconds from the first arrival (P wave) recorded at the stations.
The correct functioning of an early warning system can actually ensure more effective management of a seismic emergency from the first seconds after the occurrence of a strong earthquake, allowing rapid actions to reduce seismic exposure and risk.
The present work aims to show the functioning and performance of a particular integrated early warning system for earthquakes, currently widespread and tested in some critical areas of Italy: the software PRESTo (PRobabilistic and Evolutionary early warning SysTem, Iannacone et al., 2010; Satriano et al., 2011).
After an accurate calibration of the configuration parameters (Carannante et al., 2022), the software is currently acquiring in real time at the Milan office.
During its acquisition period, the system was able to record the events of the Marche offshore sequence (November 2022), allowing us to test the software's performances in a real early warning framework.
In fact, since the beginning of the sequence, the PRESTo software has triggered 70 probable seismic events. The analyzes are conducted by comparing the catalogue of the National Institute of Geophysics and Volcanology (http://terremoti.ingv.it/), considered as reference, with the events triggered by the system.
Searching a correspondence between the two catalogues, in terms of the origin time, we found that the system has been able to detect 12 events out of the 19 with M>=3.5 present in the INGV catalogue and recorded from 9 November to 9 December 2022 (Fig. 1).
It is important to underline that a first possible source of discrepancy between the PRESTo and ONT catalogues is ascribable to the fact that the first one is an automatic catalogue obtained using only accelerometer stations while the second one is a catalogue of events manually reviewed by an operator using velocimeters and accelerometers data.
Despite this, a first analysis shows that PRESTo has satisfactorily worked in terms of early warning, correctly detecting and estimating the hypocentral parameters of the main event of November 9, 2022 (2022-11-09 06:08:28 UTC, Ml 5.7), being a good agreement between the localization of the system (Fig. 1, red square) and that of the catalogue (Fig. 1, red circle).
In this work, the preliminary study of the software response to the sequence will be shown, with an evaluation of its performance in terms of declarative and localization capabilities.PublishedBolognaOST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impatt
Vertical seismic ground shaking in the volcanic areas of Italy: prediction equations and PSHA examples
No full textThis work introduces a new Ground Motion Model (GMM) to predict the horizontal and vertical components of PGA, PGV and acceleration response spectra up to 5s for the volcanic events in Italy. The model updates the GMM for the horizontal components, recently developed by Lanzano & Luzi [1], and shows relevant amplitudes in near-source and a frequency content richer in intermediate-to-low frequencies. The comparison with an event not used for the calibration and belonging to another volcanic district in Italy is promising for the extension of the model to other areas. Finally, we present a case study of a site, in the proximity of Mount Etna in eastern Sicily region, which allows us to evaluate the impact of these models in the framework of a Probabilistic Seismic Hazard Analysis (PSHA).Published108228OST2 Deformazione e Hazard sismico e da maremotoJCR Journa
Seismic imaging of fluid-filled inherited structures of the Northern Thessaly (Greece) seismic gap
No full texte present the first seismic imaging of the crustal volume affected by the March April 2021 Thessaly sequence by applying a 3D seismic tomography to the
aftershocks recorded by an unprecedented number of stations. The results, in
terms of VP, VS, and VP/VS ratio and earthquakes’ location parameters, depict blind
fluid-filled inherited structures within the Northern Thessaly seismic gap. The
tomographic images highlight the basal detachment accommodating the
Pelagonian nappe onto the carbonate of the Gavrovo unit. The high VP/VS
(>1.85) where most of the seismicity occurs increases from SE to NW, showing
possible fluid accumulation in the NW edge of the seismogenic volume that could
have contributed to the sequence evolution. The aftershock relocations correlate
well with the fault planes of the three mainshocks proposed by several geodetic
models, but also show additional possible faults sub-parallel and antithetical to the
main structures, not to be overlooked for future seismic risk mitigationPublished1176348JCR Journa
The Status of Space Weather Infrastructure and Research in Africa
No full textSpace weather science has been a growing field in Africa since 2007. This growth in infrastructure and human capital development has been accompanied by the deployment of ground-based observing infrastructure, most of which was donated by foreign institutions or installed and operated by foreign establishments. However, some of this equipment is no longer operational due to several factors, which are examined in this paper. It was observed that there are considerable gaps in ground-based space-weather-observing infrastructure in many African countries, a situation that hampers the data acquisition necessary for space weather research, hence limiting possible development of space weather products and services that could help address socio-economic challenges. This paper presents the current status of space weather science in Africa from the point of view of some key leaders in this field, focusing on infrastructure, situation, human capital development, and the research landscape.Published1791OSA3: Climatologia e meteorologia spazialeJCR Journa
Internet of Things for Earthquake Early Warning Systems: A Performance Comparison Between Communication Protocols
No full textEarthquake Early Warning Systems (EEWSs) characterize seismic events in real time and
estimate the expected ground motion amplitude in specific areas to send alerts before the destructive waves
arrive. Together with the reliability of the results, the rapidity with which an EEWS can detect an earthquake
becomes a focal point for developing efficient seismic node networks. Internet of Things (IoT) architectures
can be used in EEWSs to expand a seismic network and acquire data even from low-cost seismic nodes.
However, the latency and the total alert time introduced by the adopted communication protocols should be
carefully evaluated. This study proposes an IoT solution based on the message queue-telemetry transport
protocol for the waveform transmission acquired by seismic nodes and presents a performance comparison
between it and the most widely used standard in current EEWSs. The comparison was performed in
evaluation tests where different seismic networks were simulated using a dataset of real earthquakes. This
study analyzes the phases preceding the earthquake detection, showing how the proposed solution detects
the same events of traditional EEWSs with a total alert time of approximately 1.6 seconds lower.Published43183 - 43194OST4 Descrizione in tempo reale del terremoto, del maremoto, loro predicibilità e impattoJCR Journa