An SH hybrid method and shear velocity structures in the lowermost mantle beneath the central Pacific and South Atlantic Oceans

Journal of Geophysical Research: Solid Earth

Volumn 107, Issue 3, 2002, Pages

  Wen, Lianxing ^a  

^a STONY BROOK UNIVERSITY   (United States)

Author keywords

D ; Finite difference; Hybrid method; Numerical modeling; Thermochemical boundary layer; Wave propagation

Indexed keywords

CORE-MANTLE BOUNDARY; FINITE DIFFERENCE METHOD; LOWER MANTLE; SEISMIC VELOCITY; SH-WAVE; VELOCITY STRUCTURE; WAVE PROPAGATION;

(CENTRAL); (SOUTH); ATLANTIC OCEAN; PACIFIC OCEAN;

EID: 0037051477     PISSN: 21699313     EISSN: 21699356     Source Type: Journal    
DOI: None     Document Type: Article

References (21)

1. Dziewonski, A., and D. L. Anderson, Preliminary reference Earth model, Phys. Earth Planet. Inter., 25, 297-356, 1981.
2. Fouch, M. J., P. Silver, and D. E. James, Probing for shear wave anisotropy in the lowermost mantle beneath the Atlantic and Indian Oceans, Eos Trans. AGU 80(46), Fall Meet. Suppl., F759, 1999.
3. Garnero, E. J., S. P. Grand, and D. V. Helmberger, Low P-wave velocity at the base of the mantle, Geophys. Res. Lett., 23, 977-980, 1993.
4. Helmberger, D. V., Theory and application of synthetic seismograms, in Earthquakes: Observation. Theory and Interpretation, edited by H. Kanamori, pp. 173-222, Soc. It. di Fis., Bologna, Italy, 1983.
5. Helmberger, D. V., L. Wen, and X. Ding, Seismic evidence that the source of Iceland hotspot lies at the core-mantle boundary, Nature, 396, 251-255, 1998.
6. Helmberger, D. V., S. Ni, L. Wen, and J. Ritsema, Seismic evidence for ultralow-velocity zones beneath Africa and eastern Atlantic, J. Geophys. Res., 105, 23,865-23,878, 2000.
7. Lay, T., Q. Williams, and E. J. Garnero, The core-mantle boundary layer and deep Earth dynamics, Nature, 392, 461-468, 1998.
8. Mori, J., and D. V. Helmberger, Localized boundary layer below the mid-Pacific velocity anomaly identified from PcP precursor, J. Geophys. Res., 100, 20,359-20,365, 1995.
9. Niu, F., and L. Wen, Strong seismic scatterers near the core-mantle boundary west of Mexico, Geophys. Res. Lett., 28, 3557-3560, 2001.
10. Revenaugh, J., and R. Meyer, Seismic evidence of partial melt within a possibly ubiquitous low-velocity layer at the base of the mantle, Science, 277, 670-673, 1997.
11. Ricard, Y., M. A. Richards, C. Lithgow-Bertelloni, and Y. LeStunff, A geodynamic model of mantle density heterogeneity, J. Geophys. Res., 98, 21,895-21,909, 1993.
12. Ritsema, J., E. Garnero, and T. Lay, A strongly negative shear velocity gradient and lateral variability in the lowermost mantle beneath the Pacific, J. Geophys. Res., 102, 20,395-20,411, 1997.
13. Stead, R. J., and D. V. Helmberger, Numerical-analytical interfacing in two dimensions with applications to modeling NTS seismograms, Pure Appl. Geophys., 128, 153-174, 1988.
14. Vidale, J. E., and M. Hedlin, Evidence for partial melt at the core-mantle boundary north of Tonga from the strong scattering of seismic waves, Nature, 391, 682-684, 1998.
15. Virieux, J., SH-wave propagation in heterogeneous media: Velocity-stress finite-difference method, Geophysics, 49, 1933-1957, 1984.
16. Wen, L., Intense seismic scattering near the Earth's core-mantle boundary beneath the Comoros hotspot, Geophys. Res. Lett., 27, 3627-3630, 2000.
17. Wen, L., and D. L. Anderson, The fate of the slabs inferred from 130 Ma subduction and seismic tomography, Earth Planet. Sci. Lett., 133, 185-198, 1995.
18. Wen, L., and D. V. Helmberger, A 2-D P-SV hybrid method and its application to modeling localized structures near the core-mantle boundary, J. Geophys. Res., 103, 17,901-17,918, 1998a.
19. Wen, L., and D. V. Helmberger, Ultra low velocity zones near the core-mantle boundary from broadband PKP precursors, Science, 279, 1701-1703, 1998b.
20. Wen, L., P. Silver, D. James, and R. Kuehnel, Seismic evidence for a thermo-chemical boundary layer at the base of the Earth's mantle, Earth Planet. Sci. Lett., 189, 141-153, 2001.
21. Wysession, M. E., A. Langenhorst, M. J. Fouch, K. M. Fischer, G.I. Al-Eqabi, P. J. Shore, and T. J. Clark, Lateral variations in compressional/shear velocities at the base of the mantle, Science, 284, 120-125, 1999.