Whole Earth tomography from delay times of P,PcP, and PKP phases: Lateral heterogeneities in the outer core or radial anisotropy in the mantle?

Journal of Geophysical Research: Solid Earth

Volumn 105, Issue B6, 2000, Pages 13675-13696

  Boschi, Lapo ^a   Dziewonski, Adam M ^a  

^a HARVARD UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

MANTLE STRUCTURE; SEISMIC VELOCITY; TOMOGRAPHY; TRAVEL TIME;

EID: 0034631242     PISSN: 21699313     EISSN: 21699356     Source Type: Journal    
DOI: 10.1029/2000jb900059     Document Type: Article

References (31)

1. Boschi, L., and A. M. Dziewonski, "High" and "low" resolution images of the Earth's mantle: Implications of different approaches to tomographic modeling, J. Geophys. Res., 104, 25,567-25,594, 1999.
2. Dahlen, F. A., and J. Tromp, Theoretical Global Seismology, Princeton Univ. Press, Princeton, N. J., 1998.
3. Dziewonski, A. M., and D. L. Anderson, Preliminary reference Earth model, Phys. Earth Planet. Inter., 25, 297-356, 1981.
4. Ekström, G., and A. M. Dziewonski, The unique anisotropy of the Pacific upper mantle, Nature, 394, 168-172, 1998.
5. Engdahl, E. R., R. D. van der Hilst, and R. P. Buland, Global teleseismic earthquake relocation with improved travel times and procedures for depth determination, Bull. Seismol. Soc. Am., 88, 722-743, 1998.
6. Forte, A. M., A. M. Dziewonski, and R. L. Woodward, Aspherical structure of the mantle, tectonic plate motions, nonhydrostatic geoid, and topography of the core-mantle boundary, in Dynamics of Earth's deep interior and Earth Rotation, edited by J.-L. Le Mouël, D. E. Smylie and T. Herring, R. Soc., London, 1993.
7. Forte, A. M., J. X. Mitrovica, and R. L. Woodward, Seismicgeodynamic determination of the origin of excess ellipticity of the core-mantle boundary, Geophys. Res. Lett., 22, 1013-1016, 1995.
8. Garnero, E. J., and D. V. Helmberger, Travel times of S and SKS; Implications for three-dimensional lower mantle structure beneath the central Pacific, J. Geophys. Res., 98, 8225-8241, 1993.
9. Garnero, E. J., and D. V. Helmberger, Further structural constraints and uncertainties of a thin laterally varying ultralow-velocity layer at the base of the mantle, J. Geophys. Res., 103, 12,495-12,509. 1998.
10. Grand, S. P., R. D. van der Hilst and S. Widiyantoro, Global seismic tomography: A snapshot of convection in the Earth, GSA Today, 7(3), 1-7, 1997.
11. Gu, Y., A. M. Dziewonski, and G. Ekström, Radial anisotropy of the upper mantle from waveform and travel time inversions, Eos Trans. AGU, 80(17), Spring Meet. Suppl., S221, 1999.
12. Ishii, M., and J. Tromp, Normal-mode and free-air gravity constraints on lateral variations in velocity and density of Earth's mantle, Science, 285, 1169-1316, 1999.
13. Kennett, B. L. N., E. R. Engdahl, and R. P. Buland, Constraints on seismic velocities in the Earth from travel-times, Geophys. J. Int., 122, 108-124, 1995.
14. Love, A. E. H., A Treatise on the Mathematical Theory of Elasticity, 4th edition, Cambridge Univ. Press, New York, 1927.
15. Mégnin, C., H. P. Bunge, B. Romanowicz, and M. A. Richards, Imaging 3-D spherical convection models: what can seismic tomography tell us about mantle dynamics?, Geophys. Res. Lett., 24, 1299-1302, 1997.
16. Morelli, A., and A. M. Dziewonski, Topography of the core-mantle boundary and lateral homogeneity of the liquid core, Nature, 325, 678-683, 1987.
17. Obayashi, M., and Y. Fukao, P and PcP travel time tomography for the core-mantle boundary, J. Geophys. Res., 102, 17,825-17,841, 1997.
18. Paige, C. C., and M. A. Saunders, LSQR: an algorithm for sparse linear equations and sparse least squares, Trans. Math. Soft., 8, 43-71, 1982.
19. Pulliam, R. J., and P. B. Stark, Bumps on the core-mantle boundary: Are they facts or artifacts?, J. Geophys. Res., 98, 1943-1955, 1993.
20. Ritzwoller, M., G. Masters, and F. Gilbert, Observations of anomalous splitting and their interpretation in terms of aspherical structure, J. Geophys. Res., 91, 10,203-10,228, 1986.
21. Rodgers, A., and J. Wahr, Inference of core-mantle boundary topography from ISC PcP and PKP) traveltimes, Geophys. J. Int., 115, 991-1011, 1993.
22. Spakman, W., and G. Nolet, Imaging algorithms, accuracy and resolution in delay time tomography, in Mathematical Geophysics, edited by N. J. Vlaar et al., pp. 155-187, D. Reidel, Norwell, Mass., 1988.
23. Stevenson, D. J., Limits on lateral density and velocity variations in the Earth's outer core, Geophys. J. R. Astron. Soc., 88, 311-319, 1987.
24. Su, W.-J., and A. M. Dziewonski, Inner core anisotropy in three dimensions, J. Geophys. Res., 100, 9831-9852, 1995.
25. Su, W.-J., and A. M. Dziewonski, Simultaneous inversions for 3-D variations in shear and bulk velocity in the mantle, Phys. Earth Planet. Inter., 100, 135-156, 1997.
26. Su, W.-J., R. L. Woodward, and A. M. Dziewonski, Degree 12 model of shear velocity heterogeneity in the mantle, J. Geophys. Res., 99, 6945-6981, 1994.
27. Takeuchi, H., and M. Saito, Seismic surface waves, in Methods in Computational Physics, 11, pp. 217-295, Academic, San Diego, Calif., 1972.
28. van der Hilst, R. D., S. Widiyantoro, and E. R. Engdahl, Evidence for deep mantle circulation from global tomography, Nature, 386, 578-584, 1997.
29. Vasco, D. W., and L. R. Johnson, Whole Earth structure estimated from seismic arrival times, J. Geophys. Res., 103, 2633-2671, 1998.
30. Wahr, J. H., and D. de Vries, The possibility of lateral structure inside the core and its implications for nutation and Earth tide observations, Geophys. J. Int., 99, 511-519, 1989.
31. Woodhouse, J. H., A note on the calculation of travel times in a transversely isotropic Earth model, Phys. Earth Planet. Inter., 25, 357-359, 1981.