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Adjoint tomography of the Italian lithosphere
No full textThe evolution and state of geological structure at Earth’s surface is best understood with an accurate characterization of the subsurface, where fluid distribution plays a key role. We present high-resolution seismic tomographic images of tectonic and geological features of the Italian lithosphere based on ground motion recordings and obtained through an iterative procedure. Enhanced accuracy is enabled by state-of-the-art three-dimensional wavefield simulations in combination with an adjoint-state method. The resulting tomographic model characterizes the subsurface structure in terms of compressional and shear wavespeed values at remarkable resolution, corresponding to a minimum period of ~10 s. As primary findings of our work, images of the lithospheric structure in Central Italy are consistent with recent studies on the distribution of fluids and gas (CO2) within the Italian subsurface, allowing us to infer the presence of deep melted material that induces shallow gas fluxes, or traps and deep storage of gas that can be correlated with seismicity. We illuminate Mt. Etna volcano and support the hypothesis of a deep reservoir (~30 km) feeding an intermediate-depth magma-filled intrusive body, which in turn is connected to a shallow chamber. We also investigate the intriguing features of the Adriatic plate offshore of the eastern Italian coast. Tomographic evidence reveals a structure of the plate made of two distinct microplates with different fabric and behavior, and separated by the Gargano deformation zone, indicating a complex lithosphere and tectonic evolution.PublishedViennaOST1 Alla ricerca dei Motori Geodinamic
Neolithic hydroclimatic change and water resources exploitation in the Fertile Crescent
No full textIn the first millennia of the Holocene, human communities in the Fertile Crescent experienced drastic cultural and technological transformations that modified social and human-environments interactions, ultimately leading to the rise of complex societies. The potential influence of climate on this "Neolithic Revolution" has long been debated. Here we present a speleothem record from the Kurdistan Region of Iraq, covering from Early Neolithic to Early Chalcolithic periods (~ 11 to 7.3 ka, 9000-5300 BCE). The record reveals the influence of the Siberian High on regional precipitation, and shows large hydroclimatic variability at the multicentennial scale. In particular, it highlights wetter conditions between 9.7 and 9.0 ka, followed by an abrupt reduction of precipitation between 9.0 and 8.5 ka, and a wetter interval between 8.5 and 8.0 ka. A comparison with regional and local archaeological data demonstrates an influence of recorded hydroclimatic changes on settlement patterns (size, distribution, permanent vs. seasonal occupation) and on the exploitation of water resources by Neolithic to Chalcolithic populations. Our record does not show prominent hydroclimatic changes at 9.3 and 8.2 ka, thus not supporting direct influence of such rapid and widespread events on the process of Neolithization and its cultural dispersal.Published45OSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa
Italian Magnetic Network and Italian Geomagnetic Field Map at 2020.0
No full textPublishedOSA1: Variazioni del campo magnetico terrestre, imaging crostale e sicurezza del territori
A global lithospheric magnetic field model between ± 65° latitude derived from CSES satellite scalar data
No full textThe China Seismo-Electromagnetic Satellite (CSES) was launched successfully in February 2018. It is China's first satellite to measure geophysical fields with scientific goals in both space and solid earth physics. In this work, we used CSES scalar magnetic data to derive a global lithospheric magnetic field model between ±65° geographic latitudes. The nightside data from March 2018 to November 2022 under quiet space weather conditions were selected. Then, the core and external fields were removed with the CHAOS-7 model. After further data quality control, the data were used to build a lithospheric magnetic field model using a spherical harmonic analysis. The obtained CSES model was compared with the CHAOS-7, CM6, and MF7 models in terms of power spectra and anomaly details, which confirmed that the CSES scalar data had good quality and could provide a reliable lithospheric magnetic field model up to degree 42.Published107036OSA1: Variazioni del campo magnetico terrestre, imaging crostale e sicurezza del territorioJCR Journa
Environmental Reconstruction from the Identification of Magnetic Minerals in the Upper Sedimentary Infill of the Gran Dolina Cave (Burgos, Spain)
No full textThe cave system in the Sierra de Atapuerca holds one of the most important archaeological
sites for the understanding of early human occupation in Europe. Among the different cavities and
galleries, the Gran Dolina cave yielded a new hominin species coined as Homo antecessor of an Early
Pleistocene age. Encouraged by our previous results in Gran Dolina, we carried out a study to extend
and deepen our rockmagnetic investigation of the paleoenvironmental reconstruction of the
upper Gran Dolina cave based on experiments that include composition, relative concentration, and
grain size of the magnetic iron oxides present in the sediments. Based on the rockmagnetic experiments,
we identified magnetite, hematite, goethite, and possibly maghemite in changeable amounts
along the profile, which allows us to complement the existing shortage in the literature on the palaeoenvironmental
reconstruction of the site. We tentatively interpret the rockmagnetic changes recorded
in the cave sediments in terms of glacial/interglacial conditions, furnishing the base for a
better understanding for the formation conditions of this unprecedented archaeological site.Published4580OSA1: Variazioni del campo magnetico terrestre, imaging crostale e sicurezza del territorioJCR Journa
Long-term volcano evolution controlled by lateral collapse at Antuco volcano, southern Andes, Chile
No full textBeyond the catastrophic environmental effects of large (>1 km3) volcanic landslides, their impact on underlying magmatic systems remains unclear. Chemical variations in post-collapse volcanic products, alongside dramatic eruptive behaviour transitions reported from several volcanoes, imply that surface unloading directly influences subsurface magmatic processes. By combining petrologic data with magma ascent models, we track the post-collapse (<7 ka) magmatic system evolution of Antuco volcano (Chile). During the pre-collapse period, low-explosivity eruptions were sourced from a hotter and deeper storage region. However, the landslide-induced unloading and decompression reactivated a pre-existing, shallower, silicic magma reservoir, favouring more explosive activity. The pre-collapse conditions were restored after edifice regeneration over a few thousand years. Since shallow magma reservoirs are common beneath volcanoes (e.g. in Etna, Villarrica, or Fuji), similar responses could follow future lateral collapses. These findings are relevant when assessing volcanic hazards at gravitationally unstable or collapsed volcanoes on a hundred- to thousand-year timescale.Published2925V. Processi eruttivi e post-eruttiviJCR Journa
Physics-based parametrization of a FAS nonergodic ground motion model for Central Italy
No full textWe propose a new fully nonergodic ground motion model for Central Italy, which is one of the most sampled areas in the world after the occurrence of the last seismic sequences of 2009 and 2016–2017. The model predicts 69 ordinates of the Fourier Amplitude Spectrum in the magnitude range 3.2–6.5 and is constrained on a dense set of seismological and geophysical parameters (i.e. stress-drop
, shear-wave velocity in the uppermost 30 m, VS,30 and high-frequency attenuation parameter at source
and site
) made available from a non-parametric generalized inversion technique (GIT). The aim of this work is to capture the underlying physics of ground motion related to different source energy levels, as well as to the crustal and geological structure of the region, thus providing less uncertain predictions. Calibration is performed using a stepwise regression approach which has the advantage of taking a more complex functional form (advanced model) when all physical parameters are known while returning a simpler form (base model) when physical data are missing. As a result, the advanced model reproduces the reference rock motion of the region in case the site additional proxies are set to their average values (VS,30 = 1100 m/s,
=15 ms). We show that the inclusion of the set of physically-based explanatory variables in the regression has a beneficial effect in constraining the uncertainty, leading to a reduction of the high-frequency variability of about 70% on the between-event and 35% on the site-to-site. This reduction can be viewed as the result of the combination of a more effective physical description through the incorporation of the additional proxies and a calibration embedded in a completely nonergodic framework.Published4111–4137OST3 Vicino alla fagliaJCR Journa
How Are You? A Sociological Case Report of the COVID-19 Pandemic from Professionals in Italy
No full textCOVID-19 has turned our lives upside down. The first lockdown occurred in Italy in the spring of 2020, drastically disrupting people’s daily schedules, work schedules, socialisation, and relationships with
co-workers, family and friends. To overcome physical isolation, collect impressions and keep a record of the period, the “How are you?” online questionnaire has been designed as a potential conversation among friends during home confinement for all but essential reasons. What impact this situation had on people?
The study investigates some of the social and relational consequences the first lockdown in Italy had on a group of professionals in terms of similarities and differences regarding changes and limitations on their
work and daily routines, primarily focusing on the emotions felt at that time.Published1-142TM. Divulgazione ScientificaN/A or not JC
Exploring the Signature of the Apollo Medicane in the Central Mediterranean Sea Through Multi-source Data Analysis: Satellites, Radar HF, Marine Buoys, and Seismic Data in October 2021
No full textIn the last decades, the frequency of extreme weather and marine
events has drastically increased. During the last week of October 2021 an intense
Mediterranean hurricane (Medicane), named Apollo, affected many countries on
the Mediterranean coasts. Eight people died as a consequence of the floodings
from the cyclone in the countries of Tunisia, Algeria, Malta, and Italy. A preliminary
search for possible signatures of the Apollo Medicane by meteorological
satellite, radar HF, marine buoy, and seismic data is performed. This was done in a
framework of an international collaboration between Italian and Maltese partners
for the monitoring of the sea state in scenarios of climate change. The experimental
results confirm, at this preliminary stage, the possibility and the usefulness of
jointly looking at such phenomena with multiple aims of retrieving a more robust
characterization, having a backup alternative in case a primary monitoring network
gets failure, and pathing the way to heuristic and data-driven analytical and
predictive approaches to Medicanes issues.Published611-623Athens, Greec
Potential dust sources for loess deposits in Central Italy: A geochemical case study from the Loess-Paleosol-Sequence of Ponte Crispiero (Marche)
No full textIdentifying potential dust sources of Loess-Paleosol-Sequences (LPS) is important to understand past climatic and environmental conditions. For loess deposits of Central Italy different hypothesis on particle sources have been proposed, but none of them has been tested using a comprehensive geochemical approach yet.
Here we present geochemical, mineralogical and grain-size data from selected deposits of a LPS situated at Ponte Crispiero (Marche, Central Italy) to obtain first insights on the provenance of particles deposited here.
Loess deposits within the Ponte Crispiero succession are rather coarse (mostly coarse silt and fine sand) indicating a dominance of proximal dust sources. Applied geochemical indices suggest the alluvial plains of the Po River (Northern Italy) and its discharging area as major particle sources.
According to these findings, the so-called “Great Po Plain” hypothesis, that claims the presence of a vast alluvial landscape related to the sea-level drop of the Adriatic Sea during the Pleniglacial (i.e. Marine Isotope Stage MIS 4–2), may be considered as a realistic scenario. Such a considerable alluvial plain would have the potential as major source for silt and sand particles not only for the Ponte Crispiero LPS, but also for the loess on the Adriatic side of Central Italy. The main geochemical characteristics of Ponte Crispiero loess are the low concentrations of Zr and Hf and the high contents of carbonate and transition elements compared to the Upper Continental Crust and other European loess sections. Overall, this study contributes towards a better understanding of the provenance and origin of Italian loess. However, for further testing the “Great Po Plain” hypothesis, more (geochemical) investigations need to be conducted, especially in the surrounding areas of the Po plain.Published107064OSA2: Evoluzione climatica: effetti e loro mitigazioneJCR Journa