Publication Date:
2021-11-09
Description:
The aim of this study is to improve our
knowledge of the attenuation structure in the Southern
Apennines using a new amplitude ratio tomography
method (Phillips et al., Geophys Res Lett 32(21):
L21301, 2005) applied on both direct and coda
envelope measurements derived from 150 events
recorded by 47 stations of the Istituto Nazionale di
Geofisica e Vulcanologia National Seismic Network
(Rete Sismica Nazionale Centralizzata). The twodimensional
(2-D) analysis allows us to take into
account lateral crustal variations and heterogeneities
of this region. Using the same event and station
distribution, we also applied a simple 1-D methodology,
and the performance of the 1-D and 2-D path
assumptions is tested by comparing the average
interstation variance for the path-corrected amplitudes
using coda and direct waves. In general, coda
measurement results are more stable than using direct
waves when the same methodology is applied. Using
the 2-D approach, we observe more stable results for
both waves. However, the improvement is quite
small, probably because the crustal heterogeneity is
weak. This means that, for this region, the 1-D path
assumption is a good approximation of the attenuation
characteristics of the region. A comparison between Q
tomography images obtained using direct and coda
amplitudes shows similar results, consistent with the
geology of the region. In fact, we observe low Q
along the Apennine chain toward the Tyrrhenian Sea
and higher values to the east, in correspondence with
the Gargano zone that is related to the Apulia
Carbonate Platform. Finally, we compared our results
with the coda Q values proposed by Bianco et al.
(Geophys J Int 150:10–22, 2002) for the same region.
The good agreement validates our results as the
authors used a completely independent methodology.
Description:
Published
Description:
355–365
Description:
1T. Struttura della Terra
Description:
JCR Journal
Keywords:
coda Q tomography
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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