Please use this identifier to cite or link to this item: http://hdl.handle.net/2122/3536
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dc.contributor.authorallPiromallo, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italiaen
dc.contributor.authorallMorelli, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italiaen
dc.date.accessioned2008-01-14T13:03:26Zen
dc.date.available2008-01-14T13:03:26Zen
dc.date.issued1998en
dc.identifier.urihttp://hdl.handle.net/2122/3536en
dc.description.abstractWe analyse P-wave traveltimes for the Mediterranean area, using both teleseismic and regional arrivals for shallow earthquakes reported in the Bulletins of the International Seismological Centre. We model delays between pairs of 0.5° × 0.5° cells, obtaining a detailed representation of the P traveltime heterogeneities. Examination of these anomalies shows the clear presence of geographically coherent patterns—consistent with known geological features—due to significant structure in the upper mantle. We present a scheme, based on an empirical heterogeneity correction (EHC) to P-wave traveltimes, to improve earthquake location. This method provides similar benefits to those of a location procedure based on ray tracing in a 3-D model, but it is simpler and computationally more efficient. The definition of the traveltime heterogeneity model, being based on a statistical procedure, bypasses most of the critical points and possible instabilities involved in model inversion. EHC relocation, applied to Mediterranean earthquakes, allows one to predict about 70 per cent of the estimated signal due to heterogeneity and produces epicentral and origin time-shifts of, respectively, 4.22 km and 0.35 s (rms). From a synthetic experiment, in which we use the proposed algorithm to retrieve known source locations, we estimate that the rms improvement achieved by the EHC relocation over a simpler, standard, 1-D location is more than 20 per cent for both epicentral mislocation and origin time-shifts.en
dc.language.isoEnglishen
dc.publisher.nameBlackwell Publishing Ltden
dc.relation.ispartofGeophys. J. Int.en
dc.relation.ispartofseries/135(1998)en
dc.subjectearthquake locationen
dc.subjectMediterraneanen
dc.subjectP wavesen
dc.subjecttraveltimeen
dc.subjectupper mantleen
dc.titleP-wave propagation heterogeneity and earthquake location in the Mediterranean regionen
dc.typearticleen
dc.description.statusPublisheden
dc.type.QualityControlPeer-revieweden
dc.description.pagenumber232-254en
dc.subject.INGV04. Solid Earth::04.07. Tectonophysics::04.07.02. Geodynamicsen
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dc.description.obiettivoSpecifico3.3. Geodinamica e struttura dell'interno della Terraen
dc.description.journalTypeJCR Journalen
dc.description.fulltextreserveden
dc.contributor.authorPiromallo, C.en
dc.contributor.authorMorelli, A.en
dc.contributor.departmentIstituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italiaen
dc.contributor.departmentIstituto Nazionale di Geofisica e Vulcanologia, Sezione Bologna, Bologna, Italiaen
item.openairetypearticle-
item.cerifentitytypePublications-
item.languageiso639-1en-
item.grantfulltextrestricted-
item.openairecristypehttp://purl.org/coar/resource_type/c_18cf-
item.fulltextWith Fulltext-
crisitem.author.deptIstituto Nazionale di Geofisica e Vulcanologia (INGV), Sezione Roma1, Roma, Italia-
crisitem.author.deptIstituto Nazionale di Geofisica e Vulcanologia (INGV), Sezione Bologna, Bologna, Italia-
crisitem.author.orcid0000-0003-3478-5128-
crisitem.author.orcid0000-0002-7400-8676-
crisitem.author.parentorgIstituto Nazionale di Geofisica e Vulcanologia-
crisitem.author.parentorgIstituto Nazionale di Geofisica e Vulcanologia-
crisitem.classification.parent04. Solid Earth-
crisitem.department.parentorgIstituto Nazionale di Geofisica e Vulcanologia-
crisitem.department.parentorgIstituto Nazionale di Geofisica e Vulcanologia-
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