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The core–mantle boundary layer and deep Earth dynamics

Nature volume 392, pages 461–468 (1998)Cite this article

Abstract

Recent seismological work has revealed new structures in the boundary layer between the Earth's core and mantle that are altering and expanding perspectives of the role this region plays in both core and mantle dynamics. Clear challenges for future research in seismological, experimental, theoretical and computational geophysics have emerged, holding the key to understanding both this dynamic system and geological phenomena observed at the Earth's surface.

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Figure 1: Seismic-wave ray-paths from a deep focus source (circle) to a receiver (triangle) for phases that have been extensively used to image the velocity structure of the deep mantle.
Figure 2: Mollewide projections summarizing spatial patterns of recently determined seismological characteristics of the CMB boundary layer.
Figure 3: Recent high-resolution global seismic tomography models for P-wave31 and S-wave30 velocity heterogeneity near depths (Z) of 1,350 km (top row) and 2,750 km (bottom row).
Figure 4: The main classes of D″ shear-wave velocity structures.
Figure 5: Spatial patterns of large-scale mantle and core dynamical structures.
Figure 6: Diagram of possible large-scale CMB structures.

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Acknowledgements

We thank C. Lithgow-Bertelloni, R. van der Hilst and S. Grand for providing access to their models and M. Kendall for providing comments on the manuscript. This work was supported by the US National Science Foundation.

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  1. the Earth Sciences Department, University of California, Santa Cruz, 95064, California, USA

    Thorne Lay & Quentin Williams

  2. the Seismological Laboratory, University of California, Berkeley, 94720, California, USA

    Edward J. Garnero

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Correspondence to Thorne Lay.

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Lay, T., Williams, Q. & Garnero, E. The core–mantle boundary layer and deep Earth dynamics. Nature 392, 461–468 (1998). https://doi.org/10.1038/33083

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