Seismic evidence for accumulated oceanic crust above the 660-km discontinuity beneath southern Africa

Geophysical Research Letters

Volumn 30, Issue 18, 2003, Pages

  Shen, Yang ^a   Blum, John ^b  

^a UNIVERSITY OF RHODE ISLAND   (United States)

^b UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

HIGH PRESSURE EFFECTS; OCEANOGRAPHY; VELOCITY; SEISMOLOGY; SHEAR WAVES;

MANTLE; COMPRESSIONAL WAVES; HIGH PRESSURE; LOW VELOCITIES; NEGATIVE POLARITY; NEGATIVE VELOCITIES; OCEANIC CRUST; SEISMIC DISCONTINUITIES; SEISMIC EVIDENCE;

GEOPHYSICS; SHEAR FLOW;

MANTLE DISCONTINUITY; OCEANIC CRUST; SEISMIC VELOCITY; SUBDUCTION;

AFRICA; SOUTHERN AFRICA; SUB-SAHARAN AFRICA;

EID: 0348172319     PISSN: 00948276     EISSN: None     Source Type: Journal    
DOI: 10.1029/2003GL017991     Document Type: Article

References (32)

1. Abbott, D. H., The case for accretion of the tectosphere by buoyant subduction, Geophys. Res. Lett., 18, 585-588, 1991.
2. Anderson, D. L., Chemical stratification of the mantle, J. Geophys. Res., 84, 6297-6298, 1979.
3. Bickle, M. J., Implications of melting for stabilization of the lithosphere and heat loss in the Archaean, Earth Planet. Sci. Lett., 40, 301-315, 1986.
4. Blum, J., and Y. Shen, South African Archaean cratonic keels extend to the upper mantle transition zone (abstract), Eos Trans. AGU, 83, F976, 2002.
5. Dueker, K. G., and A. F. Sheehan, Mantle discontinuity structure from midpoint stacks of converted P to S waves across the Yellowstone hotspot track, J. Geophys. Res., 102, 8313-8327, 1997.
6. Duffy, T. S., and D. L. Anderson, Seismic velocities in mantle minerals and the mineralogy of the upper mantle, J. Geophys. Res., 94, 1895-1921, 1989.
7. Efron, B., and G. Gong, A leisurely look at the bootstrap, the jackknife, and cross-validation, Am. Stat., 37, 36-48, 1983.
8. Gao, S. S., P. G. Silver, and K. H. Liu, Mantle discontinuities beneath Southern Africa, Geophys. Res. Lett., 29, doi:10.1029/2001GL013834, 2002.
9. Gurrola, H., J. B. Minster, and T. Owens, The use of velocity spectrum for stacking receiver functions and imaging upper mantle discontinuities, Geophys. J. Int., 117, 427-440, 1994.
10. Hirose, K., Y. Fei, Y. Ma, and H. Mao, The fate of subducted basaltic crust in the Earth's lower mantle, Nature, 397, 53-56, 1999.
11. Hofmann, A. W., and W. M. White, Mantle plumes from ancient oceanic crust, Earth Planet. Sci. Lett., 57, 421-436, 1982.
12. Inoue, T., D. J. Weidner, P. A. Northrup, and J. B. Parise, Elastic properties of hydrous ringwoodite (γ-phase) in Mg2SiO4, Earth Planet. Sci. Lett., 160, 107-113, 1998.
13. Irifune, T., An experimental investigation of the pyroxene-garnet transformation in a pyrolite composition and its bearing on the constitution of the mantle, Phys. Earth Planet. Inter., 45, 324-336, 1987.
14. Irifune, T., and A. E. Ringwood, Phase transformations in primitive MORB and pyrolite compositions to 25 GPa and some geophysical implications, in High Pressure Research in Geophysics, edited by M. Manghanani and Y. Syono, 231-242, TERRAPUB/AGU, Washington, D. C., 1987.
15. Irifune, T., and A. E. Ringwood, Phase transformation in subducted oceanic crust and buoyancy relationships at depths of 600-800 km in the mantle. Earth Planet. Sci. Lett., 117, 101-110, 1993.
16. Ita, J., and L. Stixrude, Petrology, Elasticity, and composition of the mantle transition zone, J. Geophys. Res., 97, 6849-6866, 1992.
17. James, D. E., M. J. Fouch, J. C. VanDecar, S. van der Lee, and Kaapaval Seismic Group., Tectospheric structure beneath southern Africa, Geophys. Res. Lett., 28, 2485-2488, 2001.
18. Kanasewich, E. R., C. D. Hemmings, and T. Alpaslan, Nth-root nonlinear multichannel filter, Geophysics, 38, 327-338, 1973.
19. Karato, S., On the separation of crustal component from subducted oceanic lithosphere near the 660 km discontinuity, Phys. Earth Planet. Inter., 99, 103-111, 1997.
20. Kennett, B. L. N., and E. R. Engdahl, Travel times for global earthquake location and phase identification, Geophys. J. Int., 105, 429-466, 1991.
21. Kerr, R., and J. Lister, The spread of subducted lithospheric material along the mid-mantle boundary, Earth Planet. Sci. Lett., 85, 241-247, 1987.
22. Li, B., S. M. Rigden, and R. C. Liebermann, Elasticity of stishovite at high pressure, Phys. Earth Planet. Inter., 96, 113-127, 1996.
23. Rehkaemper, M., and A. W. Hofmann, Recycled ocean crust and sediment in Indian Ocean MORB, Earth Planet. Sci. Lett., 147, 93-106, 1997.
24. Ringwood, A. E., The pyroxene-garnet transformation in the Earth's mantle, Earth Planet. Sci. Lett., 2, 255-263, 1967.
25. Ringwood, A. E., Phase transformations and their bearing on the constitution and dynamics of the mantle, Geochim. Cosmochim. Acta, 55, 2083-2110, 1991.
26. Sautter, V., S. E. Haggerty, and S. Field, Ultradeep (>300 kilometers) ultramafic xenoliths: Petrological evidence from the transition zone, Science, 252, 827-830, 1991.
27. Shearer, P., Constraints on upper mantle discontinuities from observations of long-period reflected and converted phases, J. Geophys. Res., 96, 18,147-18,181, 1991.
28. Shen, Y., S. C. Solomon, I. Th. Bjarnason, and C. J. Wolfe, Seismic evidence for a lower-mantle origin of the Iceland plume, Nature, 395, 62-65, 1998a.
29. Shen, Y., A. F. Sheehan, K. G. Dueker, C. de Groot-Hedlin, and H. Gilbert, Upper mantle discontinuity structure beneath the southern East Pacific Rise from P-to-S converted phases, Science, 280, 1232-1234, 1998b.
30. van Keken, P. E., S. Karato, and D. A. Yuen, Rheological control of oceanic crust separation in the transition zone, Geophys. Res. Lett., 23, 1821-1824, 1996.
31. Yasuda, A., and T. Fujii, Ascending subducted oceanic crust entrained within mantle plumes, Geophys. Res. Lett., 25, 1561-1564, 1998.
32. Zhao, M., C. A. Langston, A. A. Nyblade, and T. J. Owens, Upper mantle velocity structure beneath Africa from modeling regional seismic data, J. Geophys. Res., 104, 4783-4794, 1999.