HR: 16:15h
AN: S24A-02    [Abstracts]
TI: Attenuation Of Seismic Intensity In SW Portugal-Iberia: Reconciling Historical And Instrumental Data
AU: Baptista, M A
EM: MABAPTISTA@SA.ISEL.IPL.PT
AF: CENTRO GEOFISICA UNIVERSIDADE DE LISBOA, FAC DE CIENCIAS EDC8, 6§, LISBOA, 1749 016 Portugal
AU: Baptista, M A
EM: MABAPTISTA@SA.ISEL.IPL.PT
AF: INST SUP DE ENGENHARIA DE LISBOA, RUA CONS EMIDIO NAVARRO,1, LISBOA, 1900 Portugal
AU: * MIRANDA, J M
EM: JMIRANDA@FC.UL.PT
AF: CENTRO GEOFISICA UNIVERSIDADE DE LISBOA, FAC DE CIENCIAS EDC8, 6§, LISBOA, 1749 016 Portugal
AU: LUIS, J
EM: JLUIS@UALG.PT
AF: UNIVERSIDADE DO ALGARVE, CAMPUS DE GAMBELAS, FARO, FARO, 8000 Portugal
AB: There is a growing need for quantitative seismic hazard estimations that can be used in SW Portugal as a basic tool for territorial management. These estimations rely strongly on well-constrained attenuation models which, in a region of moderate seismicity must be based on a mix of instrumental and historical studies. In this study we re-evaluated the attenuation of Medvedev, Sponheuer and Karnik (MSK) intensities for the larger and best known historical earthquakes in Portugal. These events cover a range of magnitudes between 6.0 and 8.7 and epicentral distances up to several hundreds of km. We combined this information with instrumental data available for small magnitude earthquakes (2.9 to 4.8) and epicentral distances between 40km and 400km, into a single empirical attenuation model. This model represents an improvement with regard to hazard studies because it reproduces well existing observations in terms of magnitudes and epicentral distances and also contributes to more accurate quantitative hazard estimations in SW Portugal and SW Iberia
DE: 7212 Earthquake ground motions and engineering seismology
DE: 7299 General or miscellaneous
SC: Seismology [S]
MN: Fall Meeting 2005