1,185 research outputs found
CARATTERIZZAZIONE SISMOTETTONICA DELL'AREA DI GIUNZIONE TRA IL SUDALPINO E LE DINARIDI (NE ITALIA)
No full textL’attività tettonica recente del Friuli orientale è stata indagata tramite un approccio multidisciplinare. L’ara di studio, che comprende la Pianura Friulana orientale e il bordo Prealpino Giulio, rappresenta la zona di giunzione tra i fronti SSE vergenti della Catena Sudalpina e le strutture trascorrenti destre NW-SE del Friuli orientale e Slovenia occidentale. Attualmente, sia i dati GPS che sismologici mostrano che la deformazione che si accumula ad una velocità di 2-3 mm/a viene rilasciata dall’interazione tra faglie inverse e trascorrenti. Riguardo la sismicità, la distribuzione dei terremoti mostra che gran parte degli eventi è localizzata lungo l’arco alpino e prealpino e che almeno due terremoti forti (M>6) hanno colpito l’area di studio: il terremoto del 1511 (Mw 6.3) e la sequenza del 1976-1977 (Mw 6.0 events are documented: the 1511 Mw 6.3 earthquake and the 1976-77 sequence (Mw ≤ 6.4). In more recent times, the activation of the Raune strike-slip fault in western Slovenia caused the occurrence of two seismic sequences, in 1998 (Mw 5.6) and 2004 (Mw 5.2). With the aim to further explore the involvement of the active faults of eastern Friuli during the strongest seismic events occurred in the area, this work is focused on the recent activity of the tectonic structures. Following a multidisciplinary approach, the deep 3D-geometry of 4 main fault-systems were reconstructed by combining ENI seismic lines interpretation and hypocentral distribution analysis. Successively, a morphotectonic survey was conducted along the Julian prealpine border with the aim to detect the surficial anomalies related to tectonic activity. The collected morphotectonic hints allowed to define a NW-SE elongated zone of surficial deformation, highlighting the recent activity of the Colle Villano-N Thrust (CV-N) and the Colle Villano-Borgo Faris-Cividale trasnpressive Fault-System (CV-BFC). Based on the morphostructural results, two paleoseismological trenches were dug: the Fraelacco trench across the CV-N Thrust and the Campeglio trench across the CV Thrust. At Campeglio site, the excavated trench revealed the presence of paleoliquefaction features, thus suggesting that the area experienced seismic shaking. Differently, at Fraelacco site, the displacement of the Canodusso Subsynthem (21- 23 ka cal BP) allowed to identify two deformative episodes in the last 21 ka, with the latest likely occurred in historical times
Evidence for Quaternary tectonic activity from the reconstruction of the buried quaternary bottom surface in the North-Eastern corner of the Friuli plain (NE Italy)
No full textThis study deals with the reconstruction of the buried north-easternmost sector of the Friuli plain, through
the analysis of seismic and wells subsurface data. The interest was focused on the most recent stratigraphical
horizon, here interpreted as the bottom of the Quaternary succession, with the aim to detect the Quaternary
activity of the main faults.
The eastern Friuli-western Slovenia area is characterized by the interaction of two different deformational
systems: in the western sector prevails thrust activity, in the eastern one dominates strike slip tectonics. Main
fault-systems show an about E-W trending in the W-sector and a NW-SE trending in the eastern one. Both
deformational systems are subjected to NNW-SSE compressional regime (Serpelloni et al, 2016), responsible
of their reverse or transcurrent/transpressive kinematics. Their activity is testified by the recent and historical
seismicity of the area (Mw6.63, 1348; Mw6.32, 1511; Mw6.45, 1976) (Rovida et al, 2016), but their
seismogenic role is still not completely clear. In this contest, Quaternary activity has been assumed for the
Susans Tricesimo thrust (Poli & Zanferrari, 2017), while recent paleoseismological investigations revealed
Quaternary dislocations on the Colle Villano thrust (Falcucci et al, 2018).
In this study industrial seismic lines interpretation, together with deep well logs data, allowed to reconstruct
the geometry of the main stratigraphical horizons (from the top Cretaceous-Paleogenic carbonatic platform to
the Quaternary base) and the main tectonic structures of the buried eastern Friuli plain. In particular, through the
implementation of well logs data it was possible to reconstruct the thickness of the buried alluvial Quaternary
deposits and to identify the tectonic influence on the bottom of the Quaternary surface. By merging these new
data with morphotectonic and field observations, the main buried active faults of the area were detected and
possible estimates of their activity rates were performed
Structural Complexity and Seismogenesis: The Role of the Transpressive Structures in the 1976 Friuli Earthquakes (Eastern Southern Alps, NE Italy)
No full textWe reconstructed the seismotectonic setting of the area comprising the northeastern Friuli Plain and the Julian pre-Alpine border (NE Italy) by integrating geological and seismological data. The study area represents the junction between the SSE-verging polyphase thrust-front of the south-Alpine Chain and the NW–SE-trending strike-slip faults of the eastern Friuli–western Slovenia domain. Following a multidisciplinary approach, the 3D geometry of the Susans–Tricesimo thrust system was reconstructed through the elaboration of four geological cross sections derived from the interpretation of ENI industrial seismic lines. In a second step, the seismogenic volume of the central-eastern Friuli area was investigated through hypocentral distribution analysis: the seismic events of the latest 50 years (1976–1977 and 1978–2019 time intervals) were plotted on four NE-SW-oriented seriated sections together with the fault plane’s geometry. Through this procedure, we were able to investigate the relationship between the NW-SE-striking high-angle faults, which characterize the northern Julian pre-Alps, and the WSW-verging medium-angle reverse fronts located at the piedmont of the Friuli plain, which experienced NW-SE- to NNW-SSE-oriented compression starting at least from the Pliocene. In detail, we examined the involvement of these structures during the seismic sequences of May and September 1976, in terms of activation and/or interaction. The resulting seismotectonic model highlights the interplay between transpressive/strike-slip and reverse planes. In particular, this study suggests that Predjama and Maniaglia transpressive faults strongly control the stress release and likely played a fundamental role both during the 6 May (Mw 6.5) and 15 September (Mw 6.0) Friuli earthquakes
Giulia Veronica Varisco
No full textThe headword explains the biography and the contribution of the author Giulia Varisco to the children's literatur
Valutazione della disponibilità idrica dell’Alta Pianura friulana Orientale alla luce del cambiamento climatico in atto
No full textLo studio nasce dall’esigenza del Consorzio di Bonifica della Pianura Friulana (Friuli Venezia Giulia, FVG) di individuare soluzioni irrigue per rispondere in modo efficiente alle nuove esigenze di un territorio drasticamente mutato negli ultimi decenni e nel quale la riduzione della disponibilità idrica a seguito del cambiamento climatico in atto ha comportato una limitazione anche drastica delle forniture [1]. L’area di interesse, che si estende per circa 300 km2 nell’alta pianura friulana orientale, in sinistra al T. Torre, comprende 8 comuni, con 5 comprensori irrigui alimentati prevalentemente mediante pozzi (Figura 1). Il prelievo medio annuo è pari a circa 3.700.000 m3 ma i periodi siccitosi che si susseguono con sempre maggiore frequenza hanno messo in crisi la capacità di distribuzione della risorsa. Particolare sofferenza si è verificata nel 2022 in cui l’erogazione è stata ridotta del 50%.
L’obiettivo dello studio è quantificare le risorse idriche in quest’area al fine di valutarne la disponibilità in diversi scenari di sfruttamento e di ricarica naturale interfacciando il simulatore idrologico GEOframe-NewAge [2] e quello di flusso sotterraneo FLOW3Dca.
Con un’estensione di 2800 km2, la pianura friulana è formata da depositi Quaternari con spessori che aumentano in direzione NE-SO, da 50-70 m a 900 m in prossimità del confine regionale [3]. Le caratteristiche idrogeologiche derivano dai processi deposizionali che si sono verificati nel corso del Pleistocene superiore che hanno portato ad una suddivisione del territorio in due sistemi idrogeologici in connessione:
- l’acquifero freatico dell’Alta Pianura, formato da depositi detritici grossolani di origine fluvioglaciale, prevalentemente ghiaiosi, irregolarmente cementati in orizzonti di conglomerato ed intercalati a livelli sabbiosi e argillosi;
- un acquifero multifalda della Bassa Pianura, formato da potenti depositi pelitici intercalati ad orizzonti sabbiosi e subordinatamente ghiaiosi, di origine in parte fluvioglaciale ed in parte marina, lagunare, e palustre.
La transizione tra i due sistemi è evidenziata da affioramenti di risorgiva, che si dispongono all’interno di una fascia territoriale larga alcuni km e che si sviluppa in direzione E-O per circa 100 km.
Gli studi idrogeologici effettuati hanno evidenziato alcuni indicatori di stress idrico legati sia all’aumentata pressione antropica che al cambiamento climatico in atto. La prima fase dello studio in atto si è focalizzata sull’elaborazione di dati litostratigrafici per la caratterizzazione geometrica dell’acquifero e di misure idro-metereologiche e piezometriche sull’intervallo temporale 1990-2023, utili alla quantificazione delle componenti del bilancio idrico.
Una prima analisi, condotta utilizzando 31 stazioni metereologiche e 64 pozzi (Figura 1) della rete piezometrica di monitoraggio regionale (Ufficio Idrografico e Arpa FVG), ha consentito di evidenziare per gli ultimi 15 anni (2009-2023):
- un abbassamento medio del livello piezometrico di circa 7 m con un massimo di 13 m nella parte più settentrionale dell’area;
- una riduzione delle precipitazioni medie annue dell’ordine di 200-300 mm nella pianura e fino a 700 - 900 mm nella zona montana;
- un aumento delle temperature medie annue di 0.3°C - 1°C.
Queste tendenze presuppongono una diminuzione dell’infiltrazione efficace, un aumento dell’evapotraspirazione reale e quindi una riduzione della disponibilità della risorsa idrica sia sotterranea che superficiale
Ytterbium Disilicate/Monosilicate Multilayer Environmental Barrier Coatings: Influence of Atmospheric Plasma Spray Parameters on Composition and Microstructure
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Ytterbium Disilicate/Monosilicate Multilayer Environmental Barrier Coatings: Influence of Atmospheric Plasma Spray Parameters on Composition and Microstructure
by Giulia Di Iorio,Laura Paglia *ORCID,Giulia PedrizzettiORCID,Virgilio GenovaORCID,Francesco MarraORCID,Cecilia BartuliORCID andGiovanni PulciORCID
INSTM Reference Laboratory for Materials and Surface Engineering, Sapienza University of Rome, Eudossiana 18, 00184 Rome, Italy
*
Author to whom correspondence should be addressed.
Coatings 2023, 13(9), 1602; https://doi.org/10.3390/coatings13091602
Original submission received: 10 August 2023 / Revised: 31 August 2023 / Accepted: 11 September 2023 / Published: 13 September 2023
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Abstract
SiC/SiC ceramic matrix composites (SiCf/SiC CMCs) are regarded as the new materials for the hot-section components of aircraft gas turbine engines, since they have one-third of the density of metallic superalloys, a higher temperature capability, good mechanical strength, and excellent thermal shock resistance. However, high-temperature water-vapor-rich combustion gases can induce severe surface recession phenomena in SiC/SiC leading to component failure. For this reason, it is necessary to design protective coatings, i.e., environmental barrier coatings (EBCs), able to protect the SiC/SiC surface in combustion environments. In the present work, ytterbium monosilicate (Yb2SiO5), stable when exposed to water vapor at high temperatures, and ytterbium disilicate (Yb2Si2O7), characterized by a thermal expansion coefficient closer to that of the substrate, were selected for a multilayer EBC system. EBCs were processed using the atmospheric plasma spray (APS) technique. A set of deposition parameters were tested, varying the power of the torch, and the composition and microstructure of the deposited coatings were studied in terms of porosity, crack density, and post-deposition phase retention by performing SEM, EDS, and XRD analysis. The results allow for the definition of the influence of deposition parameters on the final properties of multilayer EBC coatings
Correction to: Safety and Psychological Outcomes of Tandem t:Slim X2 Insulin Pump with Control-IQ Technology in Children, Adolescents, and Young Adults with Type 1 Diabetes: A Systematic Review
No full textThe second author name was incorrectly published as Giula Maria Smylie. The correct name is Giulia Marie Smylie. The original article has been corrected
Scrivere senza anestesia. La chiarezza di Giulia Niccolai
No full textIl saggio colloca storicamente la narratrice e poetessa Giulia Niccolai nel canone del Novecento letterario italiano discutendone poetica e cifre stilistiche. L'ampia analisi proposta tocca tutte le opere dell'autrice evidenziandone i legami intertestuali, anche tra poesia e narrativa, e i progressivi sviluppi in un arco cronologico esteso, tra anni Sessanta e primi anni Duemila. Lo studio coglie anche l'importanza dei riferimenti alle arti visive, in particolare alla fotografia, che Giulia Niccolai ha praticato in prima persona negli anni della Neoavanguardia, e alla pittura americana.The essay places the narrator and poet Giulia Niccolai in the canonical twentieth century Italian literary discussing her poetics and stylistic figures. The wide analysis proposed touches all the works of the author highlighting the intertextual links, also between poetry and narrative, and the progressive developments in an extended chronological period, between the Sixties and early Twenties. The study also captures the importance of references to the visual arts, especially photography, which Giulia Niccolai has practiced in the years of the Neo-avant-garde, and to American painting
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L'afrofuturismo tra Stati Uniti e Italia. Dalla memoria storica ai viaggi intergalattici per re-immaginare futuri postumani
No full textIn this article the author explores the cultural movement called Afrofuturism, tracing its origins, features, simbology, and its historical and political meanings. Starting from the (supposed) discoursive gap between African and African American people on one side and technology and science fiction on the other, this paradigm addresses themes related to the intersection of African Diaspora and African cultures with technology and science fiction, with the aim to recover the history of slavery and racism through the projections into alternative space-time contexts. In particular, the author explores the feminist afrofuturism perspective in order to examine the specific oppression and cultural production of African and African American women. In doing so, the author analyzes the development of afrofuturism in Italy, focusing on the work of the singer and beatmaker Karima 2G
First evidence of Holocene activity and surface diplacement of the Budoia-Aviano Thrust System in north-eastern Italy, unravelled through the integration of geological, geophysic and paleoseismological analyses
No full textWe present the findings of a multimethodological study made on the Budoia-Aviano Thrust System conducted as part of the NASA4SHA PRIN Project “Fault segmentation and seismotectonics
of active thrust systems: the Northern Apennines and Southern Alps laboratories for new Seismic Hazard Assessments in northern Italy
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