Attenuation, source parameters and site effects in the Irpinia-Basilicata region (southern Apennines, Italy)

Luciana Cantore (1) , Adrien Oth (2) , Stefano Parolai (3) , Dino Bindi (4)

1 Dipartimento di Scienze Fisiche [Naples]
2 European Center for Geodynamics and Seismology
3 Earthquake Risk and Early Warning Section
4 CEDIM - Centre for Disaster Management and Risk Reduction Technology

We derive S-wave attenuation characteristics, earthquake source parameters and site amplification functions at seismic stations used for earthquake early warning in the Irpinia-Basilicata region, using non-parametric spectral inversion of seismograms from 49 local events with = 1.5-3.1. We obtain relatively low values ( = 28 at a frequency of 1 Hz) in conjunction with a strong frequency-dependence (close to linear). The source spectra can be satisfactorily modeled using the omega-square model, with stress drops ranging between 0.01-2 MPa, and in the narrow magnitude range available for analysis, the source spectra seem to scale self-similarly. The local magnitude shows a linear correlation with moment magnitude , however with a systematic underestimation by about 0.5-magnitude units. The results obtained in this work provide important insights into the ground-motion characteristics that are required for appropriate seismic hazard assessment and are of practical relevance for a suite of applications, such as the calibration of ground-motion prediction equations or the correction for site amplification in earthquake early warning and rapid calculation of shake-maps for seismic emergency management.

Mots clés: Attenuation; Site response; Source parameters; Irpinia

Domaines: Sciences de la Terre

Luciana Cantore, Adrien Oth, Stefano Parolai, Dino Bindi. Attenuation, source parameters and site effects in the Irpinia-Basilicata region (southern Apennines, Italy). Journal of Seismology, 2011, 15 (2), pp.375-389. ⟨10.1007/s10950-011-9230-2⟩. ⟨hal-00670741⟩