HR: 0800h
AN: S51A-0231    [Abstracts]
TI: Attenuation of Macroseismic Intensity - New Relations for Different Parts of Europe
AU: * Sorensen, M B
EM: sorensen@gfz-potsdam.de
AF: GeoForschungsZentrum Potsdam, Section 5.3, Telegrafenberg, Potsdam, 14473, Germany
AU: Stromeyer, D
EM: stro@gfz-potsdam.de
AF: GeoForschungsZentrum Potsdam, Section 5.3, Telegrafenberg, Potsdam, 14473, Germany
AU: Grunthal, G
EM: ggrue@gfz-potsdam.de
AF: GeoForschungsZentrum Potsdam, Section 5.3, Telegrafenberg, Potsdam, 14473, Germany
AU: Danet, A
EM: danet@infp.ro
AF: National Institute for Earth Physics, Magurele-Bucharest 12 Calugareni st., Bucharest, Ilfov, Romania
AU: Ionescu, C
EM: viorel@infp.ro
AF: National Institute for Earth Physics, Magurele-Bucharest 12 Calugareni st., Bucharest, Ilfov, Romania
AB: When estimating strong ground motion, either using ShakeMap or other programs for seismic hazard assessment or early warning purposes, the attenuation of ground shaking is a key parameter to obtain reliable ground motion estimates. Seismic hazard studies, as well as early warning systems, are usually focused on estimating ground shaking levels in terms of peak ground acceleration (PGA), peak ground velocity (PGV) or other recorded parameters. One major drawback of such studies is the very limited strong motion dataset available in many regions even of high seismicity. Furthermore, there is hardly any direct correlation between the distribution of e.g. PGA and damage. To overcome such limitations we study strong ground motion in terms of macroseismic intensity. This makes it possible to include also historical earthquakes in an analysis by using comprehensive intensity point datasets and has the advantage of the results being directly related to the observed earthquake damages. As part of the EC project SAFER (Seismic eArly warning For EuRope), we study the attenuation of macroseismic intensities for use within early warning systems. Results will be presented for the Marmara Sea area (Turkey), the Naples area (Italy) and the Vrancea area (Romania). We consider a physically constrained attenuation model and account for the finite fault dimensions of large earthquakes in the regressions. Furthermore we derive relations between recorded ground motion parameters and macroseismic intensity for use e.g. within ShakeMap. Data from several earthquakes are joined, and for the case of Romania, anisotropy in the macroseismic field is accounted for in the derived attenuation model. Examples will be shown from implementation of the derived attenuation relation for Romania with the ShakeMap software for estimation of the intensity distributions due to previous earthquakes. Results indicate that our regression model provides a reliable estimate of macroseismic intensities for the studied regions, which can be implemented with e.g. ShakeMap for rapid estimation of the ground motion distribution after a large earthquake.
DE: 7212 Earthquake ground motions and engineering seismology
SC: Seismology [S]
MN: 2007 Fall Meeting