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The core‐mantle boundary region
Journal of Geophysical Research: Solid Earth, 1995The 75 year history of the American Geophysical Union has accompanied great advances in our understanding of the physics and chemistry of the transition zone between the Earth's core and mantle. The core‐mantle boundary (CMB) is the most significant internal boundary within our planet, buried at remote depths and probably forever hidden from direct ...
David E. Loper, Thorne Lay
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Exploring the core-mantle boundary
Physics World, 1996About 4.5 billion years ago, the Earth formed when rocky objects of various sizes that were spinning around the forming Sun collided and began to aggregate. As the planet grew larger, gravity caused denser compounds to move towards its centre and lighter ones towards the surface.
Guyot, F., Gillet, P.
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Melting of subducted basalt at the core-mantle boundary
Science, 2014The geological materials in Earth's lowermost mantle control the characteristics and interpretation of seismic ultra–low velocity zones at the base of the core-mantle boundary. Partial melting of the bulk lower mantle is often advocated as the cause, but this does not explain the nonubiquitous character of these regional seismic features ...
Andrault, Denis +5 more
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Mapping the Core-Mantle Boundary
Science, 1997Louise H. Kellogg Deep within Earth lies a boundary between the solid iron core and the mantle, where seismologists see an abrupt change in seismic wave velocity. As Kellogg discusses in her Perspective, new studies are revealing many details about this core-mantle boundary, including two reports in the same issue.
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Temperature and chemistry of the core-mantle boundary
Chemical Geology, 1995Seismic anomaly structures at the bottom of the lower mantle may be interpreted in terms of large temperature variations based on new laboratory data at very high pressure: (1) sound velocity measurements at mantle pressures show an increase in (∂lnϱ/∂lnν)P with depth (this and the strong decrease in the thermal expansion coefficient yield thermal ...
R. Boehler, A. Chopelas, A. Zerr
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Alternatives to core-mantle boundary topography
Physics of the Earth and Planetary Interiors, 1997Abstract Nuclear explosions at the French test sites in the South Pacific have been recorded at the regional seismic networks in the western United States. A total of approximately 600 good-quality, short-period seismograms were selected from an initial set of 900.
F.E. Murphy, J.W. Neuberg, A.W.B. Jacob
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Core–mantle boundary heat flow
Nature Geoscience, 2008Emerging evidence for threefold higher heat flow across the core–mantle boundary prompts a re-evaluation of the role of thermal plumes in geodynamics and the thermal history of the Earth's core and lower mantle.
Thorne Lay +2 more
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On the Ekman instability at the core–mantle boundary
Izvestiya, Physics of the Solid Earth, 2016It is shown that the instability of turbulent flows with Ekman velocity profiles in the vicinity of the core–mantle boundary leads to the formation of horizontally oriented circulating roll structures. The geophysical implications of the presence of such structures in the liquid core are explored, namely, the formation of the hot zones with enhanced ...
O. G. Chkhetiani, S. L. Shalimov
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Paleomagnetic tomography of the core-mantle boundary
Physics of the Earth and Planetary Interiors, 1990Abstract Analysis of updated global paleomagnetic data indicates that over the last 5 million years the normal and reverse polarity states are discernibly different. This difference, which can be characterized by a higher ratio of the axial quadrupole to dipole field for the reverse polarity relative to the normal polarity, is attributed to lateral ...
R.T. Merrill +2 more
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Core-mantle boundary structures and processes
2004Seismological and geodynamical observations have established the presence of a major thermo-chemical boundary layer (TCBL) in the lowermost mantle. This boundary layer plays a critical role in regulating heat flow through the core-mantle boundary, thereby influencing the dynamo-generating core flow regime.
Thorne Lay, Edward J. Garnero
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