Map of ground shaking for Pyrenees in France-Spain border
Résumé
The aim of this study is to produce automatic and fast ground shake maps for Pyrenean earthquakes with a magnitude greater than 3 considering input data from all seismic monitoring agencies operating on both sides of the France-Spain border. To produce these ground motion maps in the Pyrenean region, specific systems and protocols have been developed and implemented for receiving, in real time, data from seismic and accelerometric stations. These waveform data, temporarily stored in a server, are used in case of detection of an earthquake in the region, for computing ground motion parameters: maximum acceleration, maximum velocity and spectral acceleration for 0.3s, 1s and 3s periods; all of them necessary to compute the shake maps. Additionally, for the calculation of the maps, the system combines ground motion parameters with macroseismic intensity data, which are automatically computed and sent by several agencies, minutes and/or hours after an earthquake occurs in the region. Ground amplification factors related to the type of ground surface and the different layers in depth are also considered.