Advertisement

Anisotropy of the Uppermost Mantle in Europe as Obtained from Surface Wave Data

  • T. B. YanovskayaEmail author
  • E. L. Lyskova
  • T. Yu. Koroleva
Conference paper
Part of the Springer Proceedings in Earth and Environmental Sciences book series (SPEES)

Abstract

A new approach is proposed to study radial anisotropy of the upper mantle under the European continent. Unlike the methods used so far, we propose to interchange the order of inversion procedures. At the first stage the path-averaged velocity sections of the SH and SV waves are constructed on each path and the path-average anisotropy coefficient is calculated from these sections at different depths. At the second stage the anisotropy coefficients for individual paths are used as initial data in the tomography procedure. This approach excludes different smoothness of Rayleigh and love wave velocities, which leads to significant errors in the estimation of the anisotropy coefficient obtained from the results of SV and SH velocity tomography. The method was applied to the group velocity dispersion data of Rayleigh and Love waves from both earthquake records and ambient seismic noise along the paths crossing the European continent. The results are presented as maps of anisotropy coefficient in three 20 km layers under the Moho boundary. It was found that in the central part of the study area the anisotropy coefficient is either close to zero or characterized by small negative values (about −1%). The values of the anisotropy coefficient decrease with depth. In the sea and coastal areas, the anisotropy coefficient is positive and its values are close to those of the oceanic mantle. The causes for exceeding the velocity of SV waves with respect to the velocities of SH in the continental mantle are discussed.

Keywords

Anisotropy Upper mantle Europe Surface wave tomography 

Notes

Acknowledgements

The study was supported by the Russian Foundation for Basic Research (project no. 17-05-00522). Seismic data used in this paper have been obtained from data centers IRIS (https://www.iris.edu/hq) and GEOFON (https://geofon.gfz-potsdam.de).

References

  1. 1.
    Anderson, D.L.: Recent evidence concerning the structure and composition of the Earth’s mantle. In: Physics and Chemistry of the Earth. Pergamon Press, Oxford, pp 1–131 (1966)Google Scholar
  2. 2.
    Anderson, D.L., Regan, J.: Upper mantle anisotropy and the oceanic lithosphere. Geophys. Res. Lett. 10(9), 841–844 (1983)CrossRefGoogle Scholar
  3. 3.
    Boschi, L., Fry, B., Ekström, G., Giardini, D.: The European upper mantle as seen by surface waves. Surv. Geophys. 30, 463–501 (2009)CrossRefGoogle Scholar
  4. 4.
    Chang, S.-J., van der Lee, S., Matzel, E., Bedle, H.: Radial anisotropy along the Tethyan margin. Geophys. J. Int. 182(2), 1013–1024 (2010).  https://doi.org/10.1111/j.1365-246X.2010.04662.xCrossRefGoogle Scholar
  5. 5.
    Chen, Y., Badal, José, Zhang, Zh: Radial anisotropy in the crust and upper mantle beneath the Qinghai-Tibet Plateau and surrounding regions. J. Asian Earth Sci. 36, 289–302 (2009)CrossRefGoogle Scholar
  6. 6.
    Dziewonski, A.M., Anderson, D.L.: Preliminary reference Earth model. Phys. Earth Planet. Inter. 25, 297–356 (1981)CrossRefGoogle Scholar
  7. 7.
    Forsyth, D.W.: The early structural evolution and anisotropy of the oceanic upper mantle. Geophys J. R. Astr. Soc. 43, 103–162 (1975)CrossRefGoogle Scholar
  8. 8.
    Guo, Z., Gao, X., Wang, W., Yao, Z.: Upper- and mid-crustal radial anisotropy beneath the central Himalaya and southern Tibet from seismic ambient noise tomography. Geophys. J. Int. 189:1169–1182 (2012)CrossRefGoogle Scholar
  9. 9.
    Harkrider D.G., Anderson D.L.: Computation of surface wave dispersion for multilayered anisotropic media. Bull. Seismol. Soc. Am. 52(2), 321–332 (1962)Google Scholar
  10. 10.
    Kustowski, B., Ekström, G., Dziewonski, A.M.: The shear wave velocity structure in the upper mantle beneath Eurasia. Geophys. J. Int. 174, 978–992 (2008)CrossRefGoogle Scholar
  11. 11.
    Mitchell, B.J.: On the inversion of Love- and Rayleigh-wave dispersion and implications for the Earth structure and anisotropy. Geophys. J. R. Astr. Soc. 76, 233–341 (1984)CrossRefGoogle Scholar
  12. 12.
    Montagner, J.-P., Nataf, H.C.: On the inversion of the azimuthal anisotropy of surface waves. J. Geophys. Res. 91, 511–520 (1986)CrossRefGoogle Scholar
  13. 13.
    Nishimura, C.E., Forsyth, D.W.: The anisotropic structure of the upper mantle in the Pacific. Geophys. J. Int. 96, 203–229 (1989)CrossRefGoogle Scholar
  14. 14.
    Schaefer, J.F., Boschi, L., Becker, T.W., Kissling, E.: Radial anisotropy in the European mantle: tomographic studies explored in terms of mantle flow. Geophys. Res. Lett. 38, L23304 (2011).  https://doi.org/10.1029/2011GL049687CrossRefGoogle Scholar
  15. 15.
    Schivardi, R., Morelli, A.: EPmantle: a 3-D transversely isotropic model of the upper mantle under the European Plate. Geophys. J. Int. 185, 469–484 (2011)CrossRefGoogle Scholar
  16. 16.
    Schlue, J., Knopoff, L.: Shear-wave polarization anisotropy in the Pacific basin. Geophys. J. R. Astr. Soc. 49, 145–165 (1977)CrossRefGoogle Scholar
  17. 17.
    Shaeffer, A.J., Lebedev, S., Becker, T.W.: Azimuthal seismic anisotropy in the Earth’s uppermantle and the thickness of tectonic plates. Geophys. J. Int. 207(2), 901–933 (2016)CrossRefGoogle Scholar
  18. 18.
    Shapiro, N.M., Ritzwoller, M.H.: Monte-Carlo inversion for a global shear velocity model of the crust and upper mantle. Geophys. J. Int. 151, 88–105 (2002)CrossRefGoogle Scholar
  19. 19.
    Smith, M.L., Dahlen, F.A.: The azimuthal dependence of Love and Rayleigh wave propagation in a slightly anisotropic medium. J. Geophys. Res. 78, 3321–3333 (1973)CrossRefGoogle Scholar
  20. 20.
    Yanovskaya, T.B.: Resolution estimation in the problems of seismic ray tomography. Izv. Phys. Solid Earth 33(9), 762–765 (1997)Google Scholar
  21. 21.
    Yanovskaya, T.B., Ditmar, P.G.: Smoothness criteria in surface wave tomography. Geophys. J. Int. 102(1), 63–72 (1990)CrossRefGoogle Scholar
  22. 22.
    Yanovskaya, T.B., Kozhevnikov, V.M.: Upper mantle anisotropy beneath the Asian continent from group velocities of Rayleigh and Love waves. Russ. Geol. Geophys. 47(5), 618–625 (2006)Google Scholar
  23. 23.
    Yanovskaya, T.B., Lyskova, E.L., Koroleva, T.Yu.: Radial anisotropy in the European upper mantle from surface wave data. Izv. Phys. Solid Earth 55(2), 195–204 (2019)Google Scholar
  24. 24.
    Yanovskaya, T., Koroleva, T., Lyskova, E.: Effect of earthquakes on ambient noise surface wave tomography in upper-mantle studies. Geophys. J. Int. 205, 1208–1220 (2016).  https://doi.org/10.1093/gji/ggw083CrossRefGoogle Scholar
  25. 25.
    Yu, G., Mitchell, B.J.: Regionalized shear velocity models of the Pacific upper mantle from observed Love and Rayleigh wave dispersion. Geophys. J. R. Astr. Soc. 57, 311–341 (1979)CrossRefGoogle Scholar
  26. 26.
    Zhou, Y., Dahlen, F.A., Nolet, G.: Three-dimensional sensitivity kernels for surface wave observables. Geophys. J. Int. 158, 142–168 (2004)CrossRefGoogle Scholar
  27. 27.
    Zhou, Y., Nolet, G., Dahlen, F.A., Laske, G.: Global upper-mantle structure from finite-frequency surface-wave tomography. J. Geophys. Res. 111, B04304 (2006).  https://doi.org/10.1029/2005JB003677CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.St. Petersburg State UniversitySt. PetersburgRussia

Personalised recommendations