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

@inproceedings{Shen2003SeismicEF,
  title={Seismic evidence for accumulated oceanic crust above the 660-km discontinuity beneath southern Africa},
  author={Yang Shen and John J. Blum},
  year={2003}
}
[1] High-pressure assemblages of subducted oceanic crust are denser than the normal upper mantle but less dense than the uppermost lower mantle. Thus subducted oceanic crust may accumulate at the base of the upper mantle. Direct observational evidence for this hypothesis, however, remains elusive. We present an analysis of a negativepolarity shear wave converted from compressional wave at a seismic discontinuity near 570–600 km depth beneath southern Africa. The negative polarity of the… CONTINUE READING

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