Global shear velocity heterogeneities in the D″ layer: Inversion from Sd-SKS differential travel times

Journal of Geophysical Research: Solid Earth

Volumn 102, Issue 6, 1997, Pages 11775-11788

  Kuo, Ban Yuan ^a   Wu, Kuan Yi ^a  

^a INSTITUTE OF EARTH SCIENCES   (Taiwan)

Author keywords

[No Author keywords available]

Indexed keywords

MANTLE; S WAVE; SEISMIC VELOCITY; SPATIAL VARIATION;

EID: 0031449499     PISSN: 21699313     EISSN: 21699356     Source Type: Journal    
DOI: 10.1029/97jb00305     Document Type: Article

References (68)

1. Aki, K., and P. G. Richards, Quantitative Seismology: Theory and Methods, 932 pp., W. H. Freeman, New York, 1980.
2. Bolt, B. A., N. Mansour, and M. R. Somerville, Diffracted ScS and the shear velocity at the core boundary, Geophys. J. R. Astr. Soc., 19, 299-305, 1970.
3. Bullen, K. E., Compressibility-pressure hypothesis and Earth's interior, Mon. Not. R. Astron. Soc., Geophys. Suppl., 5, 355-368, 1949.
4. Christensen, U. R., and A. W. Hofmann, Segregation of subducted oceanic crust in the convecting mantle, J. Geophys. Res., 99, 19867-19884, 1994.
5. Cleary, J. R., The S velocity at the core-mantle boundary from observations of diffracted S, Bull. Seismol. Soc. Am. 59, 1399-1405, 1969.
6. Dziewonski, A. M., and D. L. Anderson, Preliminary reference Earth model, Phys. Earth Planet. Inter., 25, 297-356, 1981.
7. Dziewonski, A. M., T. A. Chou, and J. H. Woudhouse, Determination of earthquake source parameters from waveform data for studies of global and regional seismicity, J. Geophys. Res., 86, 2825-2852, 1981.
8. Gaherty, J. B., and T. Lay, Investigation of laterally heterogeneous shear velocity structure in D″ beneath Eurasia, J. Geophys. Res., 97, 417-435, 1992.
9. 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.
10. Garnero, E. J., and D. V. Helmberger, On seismic resolution of lateral heterogeneity in the Earth's outmost core, Phys. Earth Planet. Inter., 88, 117-130, 1995.
11. Garnero, E. J., D. V. Helmberger, and G. Engen, Lateral variations near the core-mantle boundary, Geophys. Res. Lett., 15, 609-612, 1988.
12. Garnero, E. J., D. V. Helmberger, and S. Grand, Preliminary evidence for lower mantle shear wave velocity discontinuity beneath the central Pacific, Phys. Earth Planet. Inter., 79, 335-347, 1993.
13. Grand, S. P., Mantle shear structure beneath the Americans and surrounding oceans, J. Geophys. Res., 99, 11591-11621, 1994.
14. Hales, A. L., and J. L. Roberts, The travel times of S and SKS, Bull. Seismol. Soc. Am., 60, 461-489, 1970.
15. Heiskanen, W. A., and H. Moritz, Physical geodesy, 364 pp., W. H. Freeman, New York, 1967.
16. Jeffreys, H., and K. E. Bullen, Seismological Tables, Br. Assoc. for the Adv. of Sci., London, 1940.
17. Keith, C. M., and S. Crampin, Seismic body waves in anisotropic media: Synthetic seismograms, Geophys. J. R. Astron. Soc., 49, 225-243, 1977.
18. Kendall, J.-M., and P. M. Shearer, Lateral variations in D″ thickness from long-period shear wave data, J. Geophys. Res., 99, 11,575-11,590, 1994.
19. Kendall, J. M., and C. Nangini, Lateral variations in D″ below the Caribbean, Geophys. Res. Lett., 23, 399-402, 1996.
20. Kendall, J. M., and P. G. Silver, Constraints from seismic anisotorpy on the nature of the lowermost mantle, Nature, 381, 409-412, 1996.
21. Kennett, B. L. N., Seismic Wave Propagation in Stratified Media, 342 pp., Cambridge Univ. Press, New York, 1985.
22. Kennett, B. L. N., and E. R. Engdahl, Traveltimes for global earthquake location and phase identification, Geophys. J. Int., 105, 429-465, 1991.
23. Kennett, B. L. N., and O. Gudmundsson, Ellipticity corrections for seismic phases, Geophys. J. Int., 127, 40-48, 1996.
24. Kuo, B. Y., Thermal anomalies beneath the Australian-Antarctic discordance, Earth Planet Sci. Lett., 119, 349-364, 1993.
25. Kuo, B. Y., and D. W. Forsyth, A search for split SKS waveforms in the North Atlantic, Geophys. J. Int., 108, 557-574, 1992.
26. Kuo, B. Y., D. W. Forsyth, and M. E. Wysession, Lateral heterogeneity and azimuthal anisotropy in the North Atlantic determined from SS-S differential travel times, J. Geophys. Res., 92, 6421-6436, 1987.
27. Lay, T., and D. V. Helmberger, A lower mantle S wave triplication and the shear velocity structure of D″, Geophys. J. R. Astron. Soc., 75, 799-837, 1983.
28. Li, X. D., and B. Romanowicz, Global mantle shear velocity model developed using nonlinear asymptotic coupling theory, J. Geophys. Res., 101, 22,245-22,272, 1996.
29. Liu, X. F., and A. M. Dziewonski, Lowermost mantle shear wave velocity structure (abstract), Eos Trans. AGU, 75, 663, 1994.
30. Loper, D. E., and T. Lay, The core-mantle boundary region, J. Geophys. Res., 100, 6397-6420, 1995.
31. Mitchell, B. J., and D. V. Helmberger, Shear velocities at the base of the mantle from observations of S and ScS, J. Geophys. Res., 78, 6009-6020, 1973.
32. Mondt, J. C., SH waves: Theory and observations for epicentral distances greater than 90 degrees. Phys. Earth Planet. Int., 15, 46-59, 1977.
33. Muller, G., A. H. Mula, and S. Gregersen, Amplitudes of long-period PcP and the core-mantle boundary, Phys. Earth Planet. Inter., 14, 30-40, 1977.
34. Nakanishi, I., and D. L. Anderson, Measurements of mantle wave velocities and inversion for lateral heterogeneity and anisotropy, 1, Analysis of great circle phase velocities, J. Geophys. Res., 88, 10,267-10,283, 1983.
35. Nangini, C., and J. M. Kendall, Lateral variations in D″ below the Caribbean, Geophys. Res. Lett., 23, 399-402, 1996.
36. Nishimura, C. E., and D. W. Forsyth, Rayleigh wave phase velocities in the Pacific with implications for azimuthal anisotropy and lateral heterogeneity, Geophys. J., 94, 479-501, 1988.
37. Okal, E. A., and R. J. Geller, Shear-wave velocity at the base of the mantle from profiles of diffracted SH waves, Bull. Seismol. Soc. Am., 69, 1039-1053, 1979.
38. Pulliam, R. J., and P. B. Stark, Bumps on the core-mantle boundary: Are they facts or artifacts? J. Geophys. Res., 98, 1943-1956, 1993.
39. Rampino, M. R., and R. B. Stothers, Flood basalt volcanism during the past 250 million years, Science, 241, 663-669, 1988.
40. Ray, T. W., and D. L. Anderson, Spherical disharmonies in the earth sciences and the spatial solution: Ridges, hotspots, slabs, geochemistry and tomography corrections, J. Geophys. Res., 99, 9605-9614, 1994.
41. Revenaugh, J. and T. H. Jordan, Mantle layering from S c S reverberations, 4, The lower mantle and core-mantle boundary, J. Geophys. Res., 96, 19811-19824, 1991.
42. Richards, M. A., and D. C. Engebretson, Large-scale mantle convection and the history of subduction, Nature, 355, 437-440, 1992.
43. Richards, M. A., B. H. Hager, and N. H. Sleep, Dynamically supported geoid highs over hotspots: Observation and theory, J. Geophys. Res., 93, 7690-7708, 1988.
44. Silver, P. L., and W. W. Chan, Shear wave splitting and subcontinental mantle deformation, J. Geophys. Res., 96, 16,429-16,454, 1991.
45. Sleep, N. H., Hotspots and mantle plumes: Some phenomenology, J. Geophys. Res., 95, 6715-6736, 1990.
46. Stacey, F. D., and D. E. Loper, The thermal boundary-layer interpretation of D″ and its role as a plume source, Phys. Earth Planet. Inter., 33, 45-55, 1983.
47. Steinberger, B., and R. J. O'Connell, Modeling plumes in a dynamic mantle-implications on plume sources and the distribution of hotspots (abstract), Eos, Trans. AGU, 77, 138, 1996.
48. 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.
49. Su, W. J., R. L. Woodward, and A. M. Dziewonski, Degree 12 model of shear velocity heterogeneity in the mantle, J. Geophys. Res., 99, 6945-6980, 1994.
50. Sylvander, M., and A. Souriau, Mapping S-velocity heterogeneities in the D″ region, from SmKS differential travel times, Phys. Earth Planet. Inter., 94, 1-21, 1996.
51. Tackley, P. J., D. J. Stevenson, G. A. Glatzmaier, and G. Schubert, Effects of multiple phase transitions in a three-dimensional spherical model of convection in Earth's mantle, J. Geophys. Res., 99, 15,877-15,901, 1994.
52. Tanimoto, T., Long-wavelength S-wave velocity structure throughout the mantle, Geophys. J. Int., 100, 327-336, 1990.
53. van der Hilst, R. D., Complex morphology of subducted lithosphere in the mantle beneath the Tonga trench, Nature, 374, 154-157, 1995.
54. van der Hilst, R. D., R. R. Engdahl, W. Spakman, and G. Nolet, Tomographic imaging of subducted lithosphere below northwest Pacific island arcs, Nature, 353, 37-43, 1991.
55. van der Hilst, R. D., R. R. Engdahl, and W. Spakman, Tomographic inversion of P and pP for aspheric mantle structure below the northwest Pacific region, Geophys. J. Int., 115, 264-302, 1993.
56. Vinnik, L. P., L. I. Makeyeva, A. Milev, and A. Y. Usenko, Global patterns of azimuthal anisotropy and deformations in the continental mantle, Geophys. J. Int., 111, 433-447, 1992.
57. Weber, M. P- and S- wave reflections from anomalies in the lowermost mantle, Geophys. J. int., 115, 183-210, 1993.
58. Wen, L., and D. L. Anderson, The fate of slabs inferred from seismic tomography and 130 million years of subduction, Earth Planet. Sci. Lett., 133, 185-198, 1995.
59. Woodhouse, J. H., and A. M. Dziewonski, Models of the upper and lower mantle from waveforms of mantle waves and body waves, Eos Trans. AGU, 68, 356-357, 1987.
60. Woodward, R. L., and G. Masters, Lower mantle structure from ScS-S differential travel times, Nature, 352, 231-233, 1991a.
61. Woodward, R. L., and G. Masters, Global upper mantle structure from long-period differential travel times, J. Geophys. Res., 96, 6351-6377, 1991b.
62. Wysession, M. E., and E. A. Okal, Regional analysis of D″ velocities from the ray parameters of diffracted P profiles, Geophys. Res. Lett., 16, 1417-1420, 1989.
63. Wysession, M.E., E.A. Okal, and C.R. Bina, The structure of the core-mantle boundary from diffracted waves, J. Geophys. Res., 97, 8749-8764, 1992.
64. Wysession, M. E., L. Bartko, and J. B. Wilson, Mapping the lowermost mantle using core-reflected shear waves, J. Geophys. Res., 99, 13667-13684, 1994. (Correction to "Mapping the lowermost mantle using core-reflected shear waves" by M. E. Wysession, L. Bartko, and J. B. Wilson, J. Geophys. Res., 100, 8351, 1995.)
65. Young, C. J., and T. Lay, The core-mantle boundary, Annu. Rev. Earth Planet. Sci., 15, 25-46, 1987a.
66. Young, C. J., and T. Lay, Evidence for a shear velocity discontinuity in the lowermost mantle beneath India and the Indian Ocean, Phys. Earth Planet. Inter., 49, 37-53, 1987b.
67. Young, C. J., and T. Lay, Multiple phase analysis of the shear velocity structure in the D″ region beneath Alaska, J. Geophys. Res., 95, 17,385-17,402, 1990.
68. Zhang, Y. S., and T. Tanimoto, High resolution global upper mantle structure and plate tectonics, J. Geophys. Res., 98, 9793-9823, 1993.