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Exist-fdsn-station user manual 1.0
No full textExist-fdsn-station is an open source software that implements the standard fdsnws/station web
service, integrating the application into a native XML database containing seismic stations
metadata in the StationXML file format. Through its HTTP Application Programming Interface,
extended with the PUT method for writing, this software can be used as a RESTful microservice.
The software is publicly available and licensed under a General Public License. This manual
describes all the operational phases, from installation to distribution in a production
environment, for using exist-fdsn-station to store a set of StationXML files and exposing them
efficiently with a standard fdsnws/station webservice.Published1-28OST5 Verso un nuovo MonitoraggioN/A or not JC
Some Considerations on the Seismic Event of 23 November 1980 (Southern Italy)
No full textMore than forty years after the 23 November 1980 earthquake, which devastated the Campania and
Basilicata regions, causing the destruction of a large number of towns and the death of around three thousand
people, we have tried, through a large survey, to understand how and to what extent the urban fabric and the most
affected communities have been rebuilt. Our main objective was to show, on one side, the commitment of the
scientific community, and on the other the transitions that have led from the emergency to reconstruction. Of the
Apenninic towns Conza della Campania, Laviano, Lioni, Santomenna, and others, where the devastation was
almost total, we have tried to give an iconographic vision of the post-earthquake phase through the change in the
urban layout. The partial or total reconstruction of the towns has taken place most of the time in situ, only in some
cases by relocating buildings to neighboring areas, as happened in Conza della Campania, Bisaccia and Romagnano
al Monte. Reconstruction was carried out mainly of anti-seismic buildings and only in some cases recovering preexisting
buildings in historic centres; reconstruction was completed after a very long period, in some cases lasting
over thirty years, inevitably passing through a dramatic experience of the population in temporary settlements of
various kinds, from tents, caravans, railway carriages, to containers, and finally to thermo-igloos and to
prefabricated wooden chalet-type. A very complex and detailed reconstruction was linked to factors not only
territorial, economic and political but also conditioned unfortunately by the non-negligible intervention of
organized crime.Published103-130N/A or not JC
Fast, furious, and gassy: Etna's explosive eruption from the mantle
No full textThe 3930 BP Fall Stratified (FS) eruption at Mt. Etna is a rare example of a highly explosive eruption of primitive
(picritic) magma directly from the mantle. The eruption produced ash plumes up to an estimated 20 km height,
leading to a volcanic explosivity index (VEI) 4 (subplinian). Given its volatile-rich and primitive nature, the FS
magma may have ascended rapidly from great depths to avoid fractionation and mixing within the extensive
plumbing system beneath Etna. To determine the pressures from which the FS magma derived, we perform
rehomogenization experiments on melt inclusions hosted in Fo90–91 olivines to resorb shrinkage bubbles and
determine the initial H2O and CO2 in the melt. With measured CO2 concentrations of up to 9600 ppm, volatile
solubility models yield magma storage pressures of 630–800 MPa. These correspond to depths of 24–30 km,
which are comparable to the seismologically estimated Moho. Therefore, the magma’s high CO2 concentration
must come from carbon in the mantle (likely from subducted carbonates), as opposed to assimilation of shallow
(<10 km) crustal carbonates.
Diffusion modeling of H2O and forsterite zonation profiles in clear, euhedral, and crystallographically oriented
olivines indicates rapid ascent of magma directly from its source region to the surface. Forsterite profiles exhibit
a narrow rim of growth zoning but no detectable diffusional zoning, reflecting maximum ascent times of 1–5
days. Eighteen measured H2O profiles result in remarkably uniform decompression rates of 0.47 MPa/s (95%
confidence interval of 0.16–1.28 MPa/s), which is among the fastest measured for basaltic-intermediate magmas.
These decompression rates indicate that the final stage of magma ascent over the region in which H2O degasses
(between the surface and ~ 15 km) occurred extremely fast at ~ 17.5 m/s. This eruption may provide a link
between primary magma composition and eruption intensity: we propose that the unusually explosive nature of
this picritic eruption was driven by high H2O and CO2 concentrations, which led to continuously rapid ascent
without stalling, all the way from the Moho.Published118864OSV3: Sviluppo di nuovi sistemi osservazionali e di analisi ad alta sensibilitàJCR Journa
A multi-methodological approach to record dynamics and timescales of the plumbing system of Zaro (Ischia Island, Italy)
No full textDetermining the time spans of processes related to the assembly of eruptible magma at active volcanoes is fundamental to understand magma chamber dynamics and assess volcanic hazard. This information can be recorded in the chemical zoning of crystals. Nevertheless, this kind of study is still poorly employed for the active volcanoes of the Neapolitan area (Southern Italy), in particular, for Ischia island where the risk is extremely high and this information can provide the basis for probabilistic volcanic hazard assessment. For these reasons, we acquired chemical composition on clinopyroxene crystals erupted at Ischia during the Zaro eruption (6.6 ± 2.2 ka) and performed numerical simulations of the input of mafic magma into a trachytic reservoir, in order to investigate various aspects of pre-eruptive dynamics occurring at different timescales. This event emplaced a ~ 0.1 km3 lava complex, in which the main trachytic lava flows host abundant mafic to felsic enclaves. Previous petrological investigation suggested that mafic magma(s) mixed/mingled with a trachytic one, before the eruption. In this work, the clinopyroxene zoning patterns depict the growth of crystals in different magmatic environments, recording sequential changes occurred in the plumbing system before the eruption. The evolution of the plumbing system involved a hierarchy of timescales: a few hours for magma mingling caused by mafic recharge(s) and likely occurred multiple times over a decade during which a dominant magmatic environment was sustained before the eruption. Such timescales must be considered in volcanic hazard assessment at Ischia and similar active volcanoes in densely populated areas.Published54OSV2: Complessità dei processi vulcanici: approcci multidisciplinari e multiparametriciJCR Journa
A strainmeter array as the fulcrum of novel observatory sites along the Alto Tiberina Near Fault Observatory
No full textFault slip is a complex natural phenomenon involving multiple spatiotemporal scales from seconds to days to weeks. To understand the physical and chemical processes responsible for the full fault slip spectrum, a multidisciplinary approach is highly recommended. The Near Fault Observatories (NFOs) aim at providing highprecision and spatiotemporally dense multidisciplinary near-fault data, enabling the generation of new original observations and innovative scientific products. The Alto Tiberina Near Fault Observatory is a permanent monitoring infrastructure established around the Alto Tiberina fault (ATF), a 60 km long low-angle normal fault (mean dip 20°), located along a sector of the Northern Apennines (central Italy) undergoing an extension at a rate of about 3 mm yr −1. The presence of repeating earthquakes on the ATF and a steep gradient in crustal velocities measured across the ATF by GNSS stations suggest large and deep (5-12 km) portions of the ATF undergoing aseismic creep. Both laboratory and theoretical studies indicate that any given patch of a fault can creep, nucleate slow earthquakes, and host large earthquakes, as also documented in nature for certain ruptures (e.g., Iquique in 2014, Tōhoku in 2011, and Parkfield in 2004). Nonetheless, how a fault patch switches from one mode of slip to another, as well as the interaction between creep, slow slip, and regular earthquakes, is still poorly documented by near-field observation. With the strainmeter array along the Alto Tiberina fault system (STAR) project, we build a series of six geophysical observatory sites consisting of 80-160 m deep vertical boreholes instrumented with strainmeters and seismometers as well as meteorological and GNSS antennas and additional seismometers at the surface. By covering the portions of the ATF that exhibits repeated earthquakes at shallow depth (above 4 km) with these new observatory sites, we aim to collect unique open-access data to answer fundamental questions about the relationship between creep, slow slip, dynamic earthquake rupture, and tectonic faulting.This research has been supported by the International
Continental Scientific Drilling Program (ICDP-2018/05),
the European Research Council (ERC; grant agreement no. 835012,
TECTONIC), RETURN Extended Partnership, the European Union
NextGenerationEU (National Recovery and Resilience Plan –
NRRP, Mission 4, Component 2, Investment 1.3 – D.D. 1243
2/8/2022, PE0000005), and the US Department of Energy (projects
DESC0020512 and DE-EE0008763).Published173–190OST5 Verso un nuovo MonitoraggioJCR Journa
Tracing a mantle component in both paleo and modern fluids along seismogenic faults of southern Italy
No full textAiming at understanding the source of the fluids that mineralizing within seismically active fault
zones, we investigate the noble gas isotopes (i.e., helium (He), neon (Ne), and argon (Ar)) in the fluid inclusions
(FIs) trapped in the calcite veins sampled along high‐angle fault zones of the Contursi hydrothermal basin,
southern Italy. The latter basin lies in close vicinity of the MW = 6.9, 1980 Irpinia earthquake and exposes
numerous fault scarps dissecting Mesozoic shallow‐water carbonates. The analyses of noble gases (He, Ne, Ar)
are conducted to identify the origin of the volatiles circulating along the faults at the time of calcite precipitation.
Then, outcomes of this discussions are compared with currently outgassing of deep‐sourced CO2 coupled to
mantle‐derived He in that area, whose output is larger than those from some volcanic areas worldwide. The
results indicate that He in FIs is dominated by a crustal radiogenic component (4He), and by an up to 20% of a
mantle‐derived component (3He), with a highest isotopic signature of 1.38 Ra. This value is consistent with the
highest percentage of mantle‐derived He associated to high‐flux CO2 gas emission in the investigated area (1.41
Ra). We propose that the variability of the He isotopic signature measured in primary FIs can result from early
trapping of fluid inclusions or post trapping processes and seismic activity that modify the pristine He isotopic
signature (i.e., derived from the crust and/or mantle) in groundwater along the faults during periods of
background seismicity. Such investigations are fundamental to understand fluid migration in fault systems and
the role of fluids in processes of earthquake nucleation.Publishede2024GC011816OST3 Vicino alla fagliaJCR Journa
3D seismic velocity models from local earthquake tomography furnish new insights on the Mount Etna volcano (Southern Italy)
No full textWe present a new seismotomography investigation providing a 3-D overall model of Vp, Vs and Vp/ Vs for Mt. Etna, the largest and most active volcano in Europe. We estimated and jointly evaluated P-and S-wave velocity patterns together with the Vp/Vs ratio, particularly useful to discriminate the presence of groundwater, gas, and melts and thus very precious for volcano investigations. We applied the LOTOS software to ~ 4600 crustal earthquakes that occurred in the Etnean area during the last 26 years, the longest time-interval ever analysed for Mt. Etna. This wide dataset has allowed us to characterize the volcano velocity structure getting over possible singularities due to specific eruptive phases. Our results further refined the high velocity body widely recognized in the southeastern sector of Mt. Etna by furnishing new clues on the possible former magma pathways. Moreover, the obtained 3D seismic velocity model depicted new anomalies revealing the presence of: (i) two shallow underground aquifers in the northern Etnean sector; (ii) a volume of strongly fractured rocks filled of fluids along the eastern flank; (iii) a quite deep region of probable fluid accumulation apparently not linked to the volcanic activity in the western sector. Seismic tomography based on arrival times of the P-and S-waves from local earthquakes is a powerful tool actively used for studying volcanic systems. For several volcanoes around the world, tomography allowed to successfully reconstruct the shallow-depth volcanic structure (see e.g., Refs. 1-4). Tomographic analyses have furnished, in particular, accurate pictures of the feeding systems and very precious constraints for modelling the volcanic processes also highlighting that each volcano has some peculiar features that makes it unique. In the last decades, tomographic studies have strongly benefited from the strengthening of seismic networks and computational progresses that, particularly for volcanic regions, allowed to carefully reconstruct 3D velocity models by furnishing P-and S-wave velocities and the Vp/Vs ratio, a key parameter to discriminate the presence of groundwater, gas, and melts (Refs. 5-7 , among others). On these grounds, in the present study we collected data from more than 4600 earthquakes recorded between 1997 and 2022 in order to perform a new tomographic inversion of Mt. Etna (South Italy) by applying the software LOTOS 8. Mt. Etna is the largest and most active volcano in Europe 9. It is a composite strato-volcano rising 3300 m above the sea level in eastern Sicily (Fig. 1). Mt. Etna is located at the intersection between several major structural units, where the Apennine-Maghrebian thrust belt, the Hyblean Plateau of the Africa foreland and extensional structures on the western side of the Ionian basin coexist (Fig. 1). Its activity primarily consists of nearly continuous degassing from summit craters, strombolian phases of highly variable intensity, and frequent basaltic lava flows, representing a main source of volcanic hazard in the area. Moreover, flank eruptions during which the magma bypasses the central plumbing system, intrudes as dikes and erupts along the volcano flanks, periodically occur. This kind of event produces a massive deformation affecting the entire morphology of the edifice (e.g., Refs. 10-12). In particular, in the last decade it has experienced a significant increase in eruption frequency together with the development of some of the most energetic paroxysmal sequences recorded at Mt. Etna in recent times 13. These include the three-year-long sequence of lava fountaining occurred between 2011 and 2013 14 and the very recent sequence of eruptions that took place between December 2020 and February 2022 15. Moreover, also during the writing of this paper, some episodes of explosions with ash emissions were recorded.Published28469JCR Journa
Basin inversion, drifting and hyper-extension in the Central Atlantic Ocean and Maghrebian Tethys as fluid driving mechanisms for the superimposed base metal mineralization events in the Jbel Bou Dahar carbonate-hosted Pb-Zn-Ba deposits (High Atlas, Morocco)
No full textThe Early Jurassic Jbel Bou Dahar reef-bearing carbonate platform in the eastern High Atlas, Morocco, contains
numerous carbonate-hosted and fault-controlled Pb-Zn-Ba deposits, prospects, and showings. Combined field,
petrographic and geochemical data, including REE + Y analyses, stable (C-O-S), radiogenic (Sr Pb) and noble
gas (He, Ne, Ar) isotopic compositions, record two temporally distinct metallogenic events. Both events are related
to post-rifting and inversion of the inherited Mesozoic Atlas paleorift. The ore deposits are thought to have
been formed during large-scale episodes of transtensional basin evolution, which developed as a far-field effect of
the drifting of the Central Atlantic Ocean and Maghrebian Tethys while the basin continued to invert in response
to the ongoing convergence between the African and the Eurasian plates. The paragenetically earliest Zn-rich ore
was generated in a transtensional setting coincident with the hyper-extension of Maghrebian Tethys and the initial
stages of drifting and formation of the Central Atlantic passive margin. Crustal extension and high heat fluxes
provided by the hot upwelling mantle would have triggered buoyancy-driven convection of deeply sourced fluids
and maturation of organic matter dispersed within the host carbonates to produce hydrocarbons within an extensional
basin setting. These relatively reduced Zn-rich ore-forming fluids acquired metals mainly through protracted
interaction with the country rocks including the underlying Triassic siliciclastic series and the granitic
basement rocks. Regional ENE- to E-W-trending major faults would have acted as conduits for upward fluid flow
and traps for Zn-Pb-Ba mineralization. Conversely, the late Pb-rich mineralization stage II is broadly constrained
to have occurred between ca. 70 Ma and 10 Ma and is thought to be related to the transition from orogenic shortening
(late Eocene) to post-orogenic crustal extension and exhumation (early Miocene) following Alpine orogenic
collapse. Mixing of down-ward percolating meteoric fluids and ascending rock-buffered hydrothermal
brines that had previously equilibrated with the radiogenic basement rocks along with thermochemical sulfate
reduction of transported sulfate and/or thermal cracking, would have been the main ore-forming processes that
controlled ore deposition. Given these fluid characteristics and geodynamic settings, the Jbel Bou Dahar ore field
is classified as a hybrid carbonate-hosted Pb-Zn-Ba district formed by the juxtaposition of two deposit types
rather than one progressively evolving mineralizing system. From an exploration standpoint, new delineation
here of the two metallogenic events provides valuable exploration tools for further targeting Pb Zn and barite
resources in the Atlas system of North Africa and other areas where similar orogenic belts experienced post-rift
subsidence and basin inversion.Published122451JCR Journa
Development and machine learning-based calibration of low-cost multiparametric stations for the measurement of CO2 and CH4 in air
No full textThe pressing issue of atmospheric pollution has prompted the exploration of affordable methods for measuring and monitoring air contaminants as complementary techniques to standard methods, able to produce high-density data in time and space. The main challenge of this low-cost approach regards the in-field accuracy and reliability of the sensors. This study presents the development of low-cost stations for high-time resolution measurements of CO 2 and CH 4 concentrations calibrated via an in-field machine learning-based method. The calibration models were built based on measurements parallelly performed with the low-cost sensors and a CRDS analyzer for CO 2 and CH 4 as reference instrument, accounting for air temperature and relative humidity as external variables. To ensure versatility across locations, diversified datasets were collected, consisting of measurements performed in various environments and seasons. The calibration models, trained with 70 % for modeling, 15 % for validation, and 15 % for testing, demonstrated robustness with CO 2 and CH 4 predictions achieving R 2 values from 0.8781 to 0.9827 and 0.7312 to 0.9410, and mean absolute errors ranging from 3.76 to 1.95 ppm and 0.03 to 0.01 ppm, for CO 2 and CH 4 , respectively. These promising results pave the way for extending these stations to monitor additional air contaminants, like PM, NO x , and CO through the same calibration process, integrating them with remote data transmission modules to facilitate real-time access, control, and processing for endusers.Publishede29772JCR Journa
COMPARING 1D/3D GROUND MOTION SIMULATIONS FOR EARTHQUAKES IN CENTRAL ITALY
No full textThe seismic activity known as the Amatrice-Visso-Norcia seismic sequence began on August 24th, 2016, with the M6.2 earthquake in Amatrice, Italy. This sequence included eight additional earthquakes with magnitudes above 5.0, which caused significant damage to nearby villages. The largest and most significant event occurred on October 30th, 2016, with a magnitude of 6.5 in Norcia, central Apennines. In this study, we perform physics-based simulations and investigate the ground motion variability for Norcia and Amatrice earthquakes using the Pitarka et al. (2021a) and Akinci et al. (2023) simulation approaches, respectively. We generated broad-band ground-motion acceleration time histories (0-10Hz) for these two earthquakes using frequency-wavenumber Green’s functions (FK approach) and kinematic rupture models generated with the Graves and Pitarka (2016) technique. The FK Green’s functions (GF) were computed using the propagator matrix method of Zhu and Rivera (2002) and a 1D velocity model of Central Italy (CIA) (Hermann et al., 2011). The FK-based broad-band simulation method allows for fast and realistic generation of synthetic time histories, provided that appropriate GF repository and source rupture models are available. Finally, we analyzed the performance of our 1D simulation approach by comparing our synthetic ground motions with those computed with a regional 3D velocity model and the recorded ones. We found that the FK-based simulation approach and the 1D CIA velocity model produce ground motion that compares well with recorded data throughout the region in the modeled frequency range 0-10 Hz. Because this simulation technique is very fast and reliable, it can be used to produce ground motion maps soon after a major earthquake, and in computing scenario-based ground motion for seismic hazard assessment in Central Italy.PublishedMilan