Seismic detection of folded, subducted lithosphere at the core–mantle boundary

@article{Hutko2006SeismicDO,
  title={Seismic detection of folded, subducted lithosphere at the core–mantle boundary},
  author={Alexander R. Hutko and Thorne Lay and Edward J. Garnero and Justin Revenaugh},
  journal={Nature},
  year={2006},
  volume={441},
  pages={333-336}
}
Seismic tomography has been used to infer that some descending slabs of oceanic lithosphere plunge deep into the Earth's lower mantle. The fate of these slabs has remained unresolved, but it has been postulated that their ultimate destination is the lowermost few hundred kilometres of the mantle, known as the D″ region. Relatively cold slab material may account for high seismic velocities imaged in D″ beneath areas of long-lived plate subduction, and for reflections from a seismic velocity… 
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