Back to Search
Start Over
Azimuthal anisotropy in the wider Vienna basin region: a proxy for the present-day stress field and deformation
- Source :
- Geophysical Journal International, Geophysical Journal International, Oxford University Press (OUP), 2020, 220 (3), pp.2056-2067. ⟨10.1093/gji/ggz565⟩
- Publication Year :
- 2019
- Publisher :
- Oxford University Press (OUP), 2019.
-
Abstract
- SUMMARYWe infer seismic azimuthal anisotropy from ambient-noise-derived Rayleigh waves in the wider Vienna Basin region. Cross-correlations of the ambient seismic field are computed for 1953 station pairs and periods from 5 to 25 s to measure the directional dependence of interstation Rayleigh-wave group velocities. We perform the analysis for each period on the whole data set, as well as in overlapping 2°-cells to regionalize the measurements, to study expected effects from isotropic structure, and isotropic–anisotropic trade-offs. To extract azimuthal anisotropy that relates to the anisotropic structure of the Earth, we analyse the group velocity residuals after isotropic inversion. The periods discussed in this study (5–20 s) are sensitive to crustal structure, and they allow us to gain insight into two distinct mechanisms that result in fast orientations. At shallow crustal depths, fast orientations in the Eastern Alps are S/N to SSW/NNE, roughly normal to the Alps. This effect is most likely due to the formation of cracks aligned with the present-day stress-field. At greater depths, fast orientations rotate towards NE, almost parallel to the major fault systems that accommodated the lateral extrusion of blocks in the Miocene. This is coherent with the alignment of crystal grains during crustal deformation occurring along the fault systems and the lateral extrusion of the central part of the Eastern Alps.
- Subjects :
- Seismic anisotropy
010504 meteorology & atmospheric sciences
Seismic noise
[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]
Seismic interferometry
Present day
010502 geochemistry & geophysics
01 natural sciences
Azimuth
Stress field
Europe
Geophysics
Geochemistry and Petrology
Vienna basin
Surface waves and free oscillations
Anisotropy
ComputingMilieux_MISCELLANEOUS
Geology
Seismology
0105 earth and related environmental sciences
Subjects
Details
- Language :
- English
- ISSN :
- 0956540X and 1365246X
- Database :
- OpenAIRE
- Journal :
- Geophysical Journal International, Geophysical Journal International, Oxford University Press (OUP), 2020, 220 (3), pp.2056-2067. ⟨10.1093/gji/ggz565⟩
- Accession number :
- edsair.doi.dedup.....0a2846cf71a25aebed3359d7ddba05ba
- Full Text :
- https://doi.org/10.1093/gji/ggz565⟩