Search results for " Earthquake"
showing 10 items of 81 documents
Spatio‐temporal classification in point patterns under the presence of clutter
2019
We consider the problem of detection of features in the presence of clutter for spatio-temporal point patterns. In previous studies, related to the spatial context, Kth nearest-neighbor distances to classify points between clutter and features. In particular, a mixture of distributions whose parameters were estimated using an expectation-maximization algorithm. This paper extends this methodology to the spatio-temporal context by considering the properties of the spatio-temporal Kth nearest-neighbor distances. For this purpose, we make use of a couple of spatio-temporal distances, which are based on the Euclidean and the maximum norms. We show close forms for the probability distributions o…
Mixed Non-Parametric and Parametric Estimation Techniques in R Package etasFLP for Earthquakes’ Description
2017
etasFLP is an R package which fits an epidemic type aftershock sequence (ETAS) model to an earthquake catalog; non-parametric background seismicity can be estimated through a forward predictive likelihood approach, while parametric components of triggered seismicity are estimated through maximum likelihood; estimation steps are alternated until convergence is obtained and for each event the probability of being a background event is estimated. The package includes options which allow its wide use. Methods for plot, summary and profile are defined for the main output class object. The paper provides examples of the package's use with description of the underlying R and Fortran routines.
BEFORE THE EARTHQUAKE: RECONSTRUCTION AND PRESENTATION OF LOST SITES AND BUILDINGS
2021
Abstract. The paper presents the results of a research aiming at proving the efficacy of perspective restitution from photos for the reconstruction of buildings and sites that disappeared in the past century. The case study is the town of Messina, sited at the north-eastern corner of Sicily (Italy), facing the homonymous strait that divides Sicily from the Italian peninsula; in 1908 Messina and Reggio Calabria, at the opposite side of the strait, were levelled to the ground by a powerful earthquake, followed by a tsunami.No building or monument survived the destruction: a new town with the same name took the site of Messina. Except for few strongly reshaped buildings, the memory of the stre…
Geophysical investigations along the Tyrrhenian shore of Calabria
2016
The Tyrrhenian Sea is a widely investigated basin developed in the Mediterranean area within the frame of Europe- Africa convergence and Ionian plate subduction process (Faccenna et al., 2014; Orecchio et al., 2014 and references therein). Since the Late Miocene, extension within the Tyrrhenian Sea was associated with coeval shortening in the Apennines-Maghrebide orogen and progressive southeastward rollback of the Ionian subducting plate. In this framework both extension and widespread volcanism well represented by the Vavilov and Marsili basins and the Aeolian volcanic arc, are typical features of the Tyrrhenian Sea region. Several authors (De Ritis et al., 2010; Loreto et al., 2015 and r…
PAN-AFRICAN MOBILE BELTS AS EVIDENCE FOR A TRANSITIONAL TECTONIC REGIME FROM INTRAPLATE OROGENY TO PLATE MARGIN OROGENY
1979
Pan-African belts of the African mainland and the Arabian-Nubian Shield exhibit evolutionary features which are either compatible with intracontinental ensialic development or with plate margin and Wilson cycle tectonics. Some of these belts are discussed and, considered together, they appear to reflect variations in crustal mobility during a transitional tectonic regime from intraplate to plate margin orogeny which lasted some 50. Ma from ca. 1000 Ma to ca. 500 Ma ago.
Pannello precompresso di vetromattoni assemblati a secco per la realizzazione di involucri traslucidi
2012
L’invenzione riguarda la realizzazione di un pannello di vetromattoni montati “a secco” -da impiegare per la realizzazione di involucri edilizi traslucidi anche nel caso di edifici alti- che è in grado di rispondere adeguatamente alle sollecitazioni orizzontali (quali quelle dovute a vento e sisma) grazie all’applicazione della tecnica della precompressione mondirezionale. Per offrire una risposta ai limiti imposti dalla tecnica di assemblaggio tradizionale dei vetromattoni (“ad umido”), l’applicazione della precompressione consente, infatti, di dare ai pannelli preassemblati “a secco” una rigidezza adeguata anche in direzione normale al loro piano di posa, sfruttando le buone caratteristic…
Paesi abbandonati e il ritorno della vita con l'arte
2020
In Italia, nella seconda metà del Novecento, numerosi furono i centri urbani abbandonati, a causa, ad esempio, dell’emigrazione, dei dissesti idrogeologici e degli eventi sismici. In Sicilia, i paesi di Gibellina, Salaparuta, Poggioreale, nella provincia di Trapani e Montevago, nella provincia di Agrigento, dopo il terremoto, del gennaio 1968, che colpì la parte occidentale dell’Isola, furono abbandonati e, negli anni successivi, ricostruiti, anche in siti distanti. Certamente l’attenzione iniziale fu rivolta alla costruzione delle nuove città, mentre dopo i danni dovuti alle scosse sismiche i resti degli antichi paesi furono lasciati al loro lento ed inesorabile degrado. Più recentemente, …
Geodetic and geological evidences of activetectonics in western Sicily (Italy): insights onthe seismogenic source of the 1968 Beliceearthquake sequen…
2013
The night between the January 14th and 15th 1968, a wide area of western Sicily (Italy) was shaken by a strong earthquake, the main shock of a seismic crisis that hit the region until the January 25th. The disastrous event, that is the strongest seismic event recorded in Western Sicily in historical times, caused about 370 deaths and the destruction of many villages facing the Belice river valley, which was the epicentral area for this unexpected natural disaster. The seismic sequence consisted of a main shock with M=5.9 and a series of pre-shock and aftershocks that were clustered along a NE-SW alignment. Focal planes solutions provided by many authors in the last decades show controversia…
L’USO DEI DISPOSITIVI DI RINFORZO LIGNEO NELL’ARCHITETTURA SICILIANA IN ETÀ MODERNA
2014
Il saggio studia l’uso dei dispositivi di rinforzo ligneo nelle architetture siciliane d’età moderna ponendo criticamente a confronto documenti di fabbrica, brani tratti dai trattati d’architettura, siciliani e non, e contributi offerti dalla letteratura storica non specialistica. Lo studio evidenzia la persistenza e le peculiarità d’uso di una tecnica che, molto diffusa in area mediterranea, in Sicilia si configura come una “invariante” del repertorio costruttivo tradizionale.
Traditional Architecture and seismic security. Earthquake in the Madonie inner mountain area of Sicily: damages and construction techniques
2017
Tra il 1818 e il 1819 una serie di centri siciliani concentrati nell'area montuosa delle Madonie, furono colpiti a più riprese da una sequenza di scosse sismiche che provocarono numerosi danni all’edificato storico, sia diffuso che di pregio. Il contributo intende indagare i danni e le conseguenti ricostruzioni, con particolare riferimento alle tipologie edilizie e alle tecniche costruttive adottate prima e dopo il sisma. L'azione di verifica e monitoraggio delle condizioni delle fabbriche e i conseguenti interventi di consolidamento e riparazione sono efficacemente documentati in testi a stampa e nei report coevi al sisma e –soprattutto- da una copiosa documentazione archivistica. Si ident…