Upper crustal azimuthal anisotropy across the contiguous U.S. determined by Rayleigh wave ellipticity

Upper crustal azimuthal anisotropy across the contiguous U.S. determined by Rayleigh wave ellipticity

Constraints on upper crustal seismic anisotropy provide insight into the local stress orientation and structural fabric, but such constraints are scarce except in areas with dense recordings of local seismicity. We investigate directionally dependent Rayleigh wave ellipticity, or Rayleigh wave H/V (horizontal to vertical) amplitude ratios, between 8 and 20 s period across USArray to infer azimu...

Depth dependent azimuthal anisotropy in the western US upper mantle

Lateral Heterogeneity and Azimuthal Anisotropy of the Upper Mantle: Love and Rayleigh Waves 100-250 s

The lateral heterogeneity and apparent anisotropy of the upper mantle are studied by measuring Rayleigh and Love wave phase velocities in the period range 100-250 s. Spherical harmonic descriptions of the lateral heterogeneity are obtained for order and degree up to 1 = m = 10. Slow regions are evident at the East Pacific Rise, northeast Africa, Tibet, Tasman Sea, southwestern North America, an...

Length scales, patterns and origin of azimuthal seismic anisotropy in the upper mantle as mapped by Rayleigh waves

Thorsten W. Becker,1 Göran Ekström,2 Lapo Boschi3 and John H. Woodhouse4 1Department of Earth Sciences, University of Southern California, 3651 Trousdale Parkway, Los Angeles CA 90089-0740, USA. E-mail: [email protected] 2Department of Earth and Environmental Sciences, Lamont-Doherty Earth Observatory, Palisades, NY 10964, USA 3Eidgenössische Technische Hochschule, Zürich, Switzerland 4Department of ...

3-D crustal structure of the western United States: application of Rayleigh-wave ellipticity extracted from noise cross-correlations

Fan-Chi Lin,1 Victor C. Tsai2 and Brandon Schmandt3 1Department of Geology and Geophysics, The University of Utah, Salt Lake City, UT 84112, USA. E-mail: [email protected] 2Seismological Laboratory, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA 3Department of Earth and Planetary Science, The University of New Mexico, Albuquerque, NM...