HR: 0830h
AN: S51E-0096    [PDF]
TI: Ground Motion Scaling in Southern Spain
AU: * Mancilla, F
EM: flor@iag.ugr.es
AF: Instituto Andaluz de Geofisica. Universidad de Granada, Campus de Cartuja. s/n, Granada, 18071 Spain
AU: Herrmann, R B
EM: rbh@eas.slu.edu
AF: Department of Earth and Atmospheric Sciences, Saint Louis University, 3507 Laclede, Saint Louis, MO 63103 United States
AU: Morales, J
EM: morales@iag.ugr.es
AF: Instituto Andaluz de Geofisica. Universidad de Granada, Campus de Cartuja. s/n, Granada, 18071 Spain
AB: We quantify the attenuation of ground motion with distance in southern Spain, using 4946 vertical component velocity recordings from 1015 local and regional earthquakes recorded at the Andalusian short-period network. Epicentral distances range from 3.19 to 600 km and magnitudes from 1.0 to 5.1. We evaluate the 0.5 to 14 Hz frequency band, and we parameterize the diminution of seismic wave amplitude with distance in a two step process: first, specification of Peak S-wave motions in terms of EXCITATION, DISTANCE and SITE terms, followed by modeling in terms of geometrical spreading, frequency dependent Q, and distance dependent duration. We compare our results with previous results obtained in Italy using the same methodology. This determination is an important component of seismic hazard estimation for the South of the Iberian Peninsula. Recent seismicity in the region is characterized by low-to-moderate magnitudes (Mw$<5.5$) and a diffuse geographical distribution. From historical records, however, the seismic hazard at this portion of the Africa-Eurasian plate boundary is potencially high. Since 1500, southern Spain experienced 10 earthquakes with maximun intensities of IX or X (MSK scale), and the largest shallow event in the last century was the 1910 ($m_b$ = 6.3) Adra earthquake.
DE: 7212 Earthquake ground motions and engineering
SC: Seismology [S]
MN: 2003 Fall Meeting