Macroseismic intensity attenuation for Metropolitan France: importance of the epicentral intensity.

Research areas:
Year:
2006
Authors:
Journal:
COMPTES RENDUS GEOSCIENCE
Volume:
338
Number:
9
Pages:
596-605
Month:
July
ISSN:
1631-0713
BibTex:
Abstract:
The main result of this work is to show that macroseismic intensity decay with distance strongly depends on the epicentral intensity. An attenuation law that takes this parameter into account is proposed for Metropolitan France, from the analysis of SISFRANCE macroseismic database. Such a model significantly reduces the difference between observed and theoretical intensities. A map of the attenuation variations is also set up for Metropolitan France. No major site effects are observed, but at a broad scale, young Alpine regions display a stronger attenuation than old Hercynian regions.