Publication Date:
2017-04-04
Description:
Acceleration time series recorded by the Italian Strong Motion Network (RAN) during the
October 31, 2002 (Mw=5.8), Molise earthquake, are employed in order to investigate source
effects on the ground motion in the epicentral area. We consider two different seismogenic
sources: a fault model inferred from inversion of teleseismic, regional and local seismic signals
[Vallée and Di Luccio, 2005], and a fault model based on seismotectonic data [Basili and Vannoli,
2005].
Both source studies suggest a deep location of the earthquake fault plane (ranging from 6.0 to 20.1
km and from 12.0 to 19.9 km, respectively), however, with considerably different fault lengths
(5.2 and 10.5 km, respectively), and widths (14.2 and 8 km, respectively). Due to these
differences, only the second model allows for effective horizontal unilateral rupture propagation.
Finite fault effects are modelled by the Deterministic-Stochastic-Method (DSM) [Pacor et al.,
2005], and the Hybrid Integral-Composite source model (HIC) [Gallovic and Brokesova, 2006]. In
both methods k-square slip distributions on the faults are considered.
We simulate the October 31, 2002 earthquake considering: 1) Vallée and Di Luccio [2005]
faultwith a bilateral rupture propagation, and 2) Basili and Vannoli [2005] fault with unilateral
directions of the rupture propagation. The spectral attenuation is modelled using a regional
estimate of the quality factor [Castro et al., 2004] and k values estimated from acceleration
records. Comparison between synthetic and recorded data at nearby stations (hypocentral distances
〈 60 km) performed in terms of frequency content and peak ground motion, favours the model
with unilateral propagation of the rupture.
Assuming the source model with unilateral rupture propagation, we utilize both asymptotic and
full wave field methods in order to simulate ground shaking scenarios for an area extending up to
150 km epicentral distance. These results are then subjected to comparison with peak ground
accelerations recorded in the far field.
Description:
Unpublished
Description:
Geneva, Switzerland
Description:
open
Keywords:
Earthquake
;
Ground motion
;
04. Solid Earth::04.06. Seismology::04.06.04. Ground motion
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
Conference paper
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