22 research outputs found
Standardization of Seismic Tomographic Models and Earthquake Focal Mechanisms Datasets Based on Web Technologies, Visualization with Keyhole Markup Language
We present two projects in seismology that have been ported to web technologies, which provide results in Keyhole Markup Language (KML) visualization layers. These use the Google Earth geo-browser as the flexible platform that can substitute specialized graphical tools to perform qualitative visual data analyses and comparisons. The Network of Research Infrastructures for European Seismology (NERIES) Tomographic Earth Model Repository contains datasets from over 20 models from the literature. A hierarchical structure of folders that represent the sets of depths for each model is implemented in KML, and this immediately results into an intuitive interface for users to navigate freely and to compare tomographic plots. The KML layer for the European-Mediterranean Regional Centroid-Moment Tensor Catalog displays the focal mechanism solutions or moderate magnitude Earthquakes from 1997 to the present. Our aim in both projects was to also propose standard representations of scientific datasets. Here, the general semantic approach of XML has an important impact that must be further explored, although we find the KML syntax to be more shifted towards detailed visualization aspects. We have thus used, and propose the use of, Javascript Object Notation (JSON), another semantic notation that stems from the web-development community that provides a compact, general-purpose, data-exchange format
Materials for the catalogue of Italian earthquakes: A reappraisal of minor seismicity
Nel catalogo CPTI04 [Gruppo di Lavoro
CPTI, 2004], un numero consistente di terremoti
è tuttâora privo di uno studio di riferimento recente.
Nel corso di questo lavoro sono stati studiati
851 di questi terremoti: si tratta di eventi con Io
tra il V-VI e il VII grado MCS, verificatisi dal
1198 al 1980 ma soprattutto nel Novecento, i cui
parametri epicentrali derivano dal catalogo PFG
[Postpischl, 1985a]. Questi eventi sono stati sottoposti
a una sistematica revisione, adottando una
procedura speditiva omogenea e rigorosa che ha
permesso di elaborare nuovi parametri per 741 su
851 terremoti studiati.
Nei restanti 110 casi lo studio ha portato
a riconoscere 26 degli eventi studiati come inesistenti
o estremamente dubbi. In 84 casi, infine,
le informazioni storiche raccolte non sono risultate
sufficienti per lâelaborazione di nuovi parametri.
Il valore di intensità epicentrale è diminuito
nel 72% dei casi e aumentato solo nel
4.5% di essi; il 50 % circa dei terremoti rivisti
ha unâintensitĂ epicentrale inferiore alla soglia
attualmente adottata dal catalogo. Si notano
anche significative variazioni nella localizzazione
di alcuni dei terremoti rivisti.
I risultati del lavoro sono riassunti in 851
schede di sintesi e circa 12.500 punti dâintensitĂ
osservati, che sono presentati in questo
Quaderno insieme a una sintetica introduzione
metodologica
Materiali per un catalogo dei terremoti italiani: eventi sconosciuti, rivalutati o riscoperti
The large-scale studies of historical seismology carried out in Italy and Europe in the last decades were mostly aimed at
improving knowledge about earthquakes that were already listed in the extant parametric catalogues, rather than at
identifying earthquakes that were not listed in them.
From 1992 onwards, some of the authors of this study started to look for such âforgottenâ earthquakes in different ways (by
systematic surveys of serial historical sources, or by extensive investigation of local records in selected areas). More than 2000
pieces of evidence related to as many earthquakes not listed by any seismological compilations/catalogues were thus identified.
In 2003 all resources were pooled in a common effort, meant to complete the revision of minor âknownâ earthquakes carried
out by Molin et al. [2008] with a study of the most relevant âunknownâ earthquakes identified so far. We present here the
results of the analysis of 227 damaging earthquakes, 155 of which are âunknownâ to the seismological tradition. Other 72
events were listed in the Postpischl [1985] catalogue, but not in newer parametric catalogues, no evidence of damage being
available for them at the time: such evidence has now been found and, in 21 cases at least, it allows for a significant re-evaluation
of macroseismic intensity
Standardization of Seismic Tomographic Models and Earthquake Focal Mechanisms Datasets Based on Web Technologies, Visualization with Keyhole Markup Language
We present two projects in seismology that have been ported to web technologies, which provide results in Keyhole Markup Language (KML) visualization layers. These use the Google Earth geo-browser as the flexible platform that can substitute specialized graphical tools to perform qualitative visual data analyses and comparisons. The Network of Research Infrastructures for European Seismology (NERIES) Tomographic Earth Model Repository contains datasets from over 20 models from the literature. A hierarchical structure of folders that represent the sets of depths for each model is implemented in KML, and this immediately results into an intuitive interface for users to navigate freely and to compare tomographic plots. The KML layer for the European-Mediterranean Regional Centroid-Moment Tensor Catalog displays the focal mechanism solutions or moderate magnitude Earthquakes from 1997 to the present. Our aim in both projects was to also propose standard representations of scientific datasets. Here, the general semantic approach of XML has an important impact that must be further explored, although we find the KML syntax to be more shifted towards detailed visualization aspects. We have thus used, and propose the use of, Javascript Object Notation (JSON), another semantic notation that stems from the web-development community that provides a compact, general-purpose, data-exchange format.Published47-563.1. Fisica dei terremotiJCR Journalope
Standardization of Seismic Tomographic Models and Earthquake Focal Mechanisms Datasets Based on Web Technologies, Visualization with Keyhole Markup Language
We present two projects in seismology that have been ported to web technologies, which
provide results in Keyhole Markup Language (KML) visualization layers. These use the Google Earth geo-browser as the flexible platform that can substitute specialized graphical tools to perform qualitative visual data analyses and comparisons. The Network of Research Infrastructures for European Seismology (NERIES) Tomographic Earth Model Repository contains datasets from over 20 models from the literature. A hierarchical structure of folders that represent the sets of depths for each model is implemented in KML, and this immediately results into an intuitive interface for users to navigate freely and to compare tomographic plots. The KML layer for the European-Mediterranean Regional Centroid-Moment Tensor Catalog displays the focal mechanism solutions or moderate magnitude Earthquakes from 1997 to the present. Our aim in both projects was to also propose standard representations of scientific datasets. Here, the general semantic approach of XML has an important impact that must be further explored, although we find the KML syntax to be more shifted towards detailed visualization aspects. We have thus used, and propose the use of, Javascript Object Notation (JSON), another semantic notation that stems from the web-development community that provides a compact, general-purpose, data-exchange format
Materiali per un catalogo dei terremoti italiani: eventi sconosciuti, rivalutati o riscoperti
The large-scale studies of historical seismology carried out in Italy and Europe in the last decades were mostly aimed at
improving knowledge about earthquakes that were already listed in the extant parametric catalogues, rather than at
identifying earthquakes that were not listed in them.
From 1992 onwards, some of the authors of this study started to look for such âforgottenâ earthquakes in different ways (by
systematic surveys of serial historical sources, or by extensive investigation of local records in selected areas). More than 2000
pieces of evidence related to as many earthquakes not listed by any seismological compilations/catalogues were thus identified.
In 2003 all resources were pooled in a common effort, meant to complete the revision of minor âknownâ earthquakes carried
out by Molin et al. [2008] with a study of the most relevant âunknownâ earthquakes identified so far. We present here the
results of the analysis of 227 damaging earthquakes, 155 of which are âunknownâ to the seismological tradition. Other 72
events were listed in the Postpischl [1985] catalogue, but not in newer parametric catalogues, no evidence of damage being
available for them at the time: such evidence has now been found and, in 21 cases at least, it allows for a significant re-evaluation
of macroseismic intensity.Published1-535.1. TTC - Banche dati e metodi macrosismiciN/A or not JCRope
Looking for missing earthquake traces in the Ferrara-Modena plain: an update on historical seismicity
The area most affected by the May-June 2012 Emilia sequence has a centuries-old seismic history with comparatively moderate maximum magnitude values, on a par with those on record in the nearby Reggiano-Parmense area but less significant than those known to occur in the northern Apennines and greatly lower than those on record in the most seismically active zones of the Italian peninsula.
According to the latest issue of the Italian seismic catalogue (Rovida et al., 2011) Mw~5.5 earthquakes are known to have occurred near Ferrara (1346, 1561) and in the areas of Finale Emilia-Bondeno (1574, 1908, 1986), Mantua (1901) and Cento (1922). This picture might be incomplete, as suggested by the recent discovery of a previously unknown earthquake occurred in 1639 with I max 7-8 MCS in Finale Emilia (Camassi et al., 2011b).The incompleteness of the current picture of local seismicity is shown by a number of previously unknown, moderately damaging local earthquakes retrieved by recent studies: a few particularly interesting cases are described
EuropeanâMediterranean Regional Centroid Moment Tensor catalog: Solutions for 2005â2008
Since 1997 we maintain and systematically update the EuropeanâMediterranean Regional Centroid
Moment Tensor (RCMT) catalog, which contains seismic-moment tensors for earthquakes with moderate
magnitude (4.5<M< 5.5) in the Mediterranean and European regions. We present 354 new solutions for
the period 2005â2008. The Catalog now spans 12 years and contains more than 1000 definitive RCMT
solutions. In addition to definitive solutions, we maintain and update a dataset of recent âquickâ solutions
that are computed soon after an earthquake occurs using the more limited set of data available in quasi-
real time. We investigate the reliability of the moment tensor results in the RCMT catalog. Comparison
with Global CMT results, which is possible for the larger events (M< 5.0) in the RCMT catalog, shows
that for 75% of the events, the Kagan angle measure of the similarity of two moment tensors is smaller
than 20âŚ, reflecting good agreement of the results. We describe improvements and enhancements in the
dissemination of the RCMT results through our website