Melting-induced stratification above the Earth’s inner core due to convective translation

@article{Alboussire2010MeltinginducedSA,
  title={Melting-induced stratification above the Earth’s inner core due to convective translation},
  author={Thierry Alboussi{\`e}re and R. Deguen and Mickael Melzani},
  journal={Nature},
  year={2010},
  volume={466},
  pages={744-747}
}
In addition to its global North–South anisotropy, there are two other enigmatic seismological observations related to the Earth’s inner core: asymmetry between its eastern and western hemispheres and the presence of a layer of reduced seismic velocity at the base of the outer core. This 250-km-thick layer has been interpreted as a stably stratified region of reduced composition in light elements. Here we show that this layer can be generated by simultaneous crystallization and melting at the… 

Melting of the Earth’s inner core

Here geodynamo simulations are used to show that variations in heat flow from mantle convection are transferred to the inner-core boundary and can be large enough to cause heat to flow into the inner core.

Thermal convection in Earth's inner core with phase change at its boundary

Inner core translation, with solidification on one hemisphere and melting on the other, provides a promising basis for understanding the hemispherical dichotomy of the inner core, as well as the

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Seismic P velocity structure is determined for the upper 500 km of the inner core and lowermost 200 km of the outer core from differential travel times and amplitude ratios. Results confirm the

Sharp hemisphere boundaries in a translating inner core

Geodynamic models of a convectively translating inner core have recently been proposed that would account for the seismically observed differences in isotropic velocity between the eastern and

Heterogeneity and Anisotropy of Earth's Inner Core

Seismic observations provide strong evidence that Earth's inner core is anisotropic, with larger velocity in the polar than in the equatorial direction. The top 60–80 km of the inner core is

Distinct layering in the hemispherical seismic velocity structure of Earth's upper inner core

The existence of hemispherical variation in the Earth's inner core is well-documented, but consensus has not yet been reached on its detailed structure. The uppermost layers are a region of

Convection in the Earth's inner core

The feasibility of thermal and compositional convection in Earth’s inner core

Inner core convection, and the corresponding variations in grain size and alignment, has been proposed to explain the complex seismic structure of the inner core, including its anisotropy, lateral
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