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| Titel |
A three-component array and some statistics: quantifying ambient surface wave anisotropy in the Paris Basin |
| VerfasserIn |
Nima Riahi, Erik Saenger |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250080652
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| Zusammenfassung |
| Three-component seismic arrays can be used to estimate local phase velocities of Love and
Rayleigh waves as a function of propagation backazimuth. We show frequency resolved
results from such an analysis in the range 0.2-1.1Â Hz based on several days of noise data
from a temporary array in the Paris Basin. Above 0.4Â Hz we observe higher surface wave
modes which exhibit wider backazimuth ranges compared to the microseism peak
frequencies at 0.2Â Hz. Anisotropy in phase velocity is quantified by fitting the Smith and
Dahlen (1973) approximation to the observations. We find that both 2θ and 4θ variation
exists for Rayleigh and Love waves over much of the band 0.4-1.1Â Hz. Statistical
significance of the anisotropy parameters is established using bootstrap confidence
intervals. The observed fast directions from 0.4-1.1Â Hz are roughly aligned with
the preferred shallow fault direction ( |
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