Lopsided Growth of Earth's Inner Core

  title={Lopsided Growth of Earth's Inner Core},
  author={Marc Monnereau and Marie Calvet and Ludovic Margerin and Annie Souriau},
  pages={1014 - 1017}
Clearing Up the Inner Core The behavior of Earth's core controls the planet's heat budget and magnetic field, yet its structure remains enigmatic. For instance, the seismic properties of the solid inner core suggest hemispherical structural asymmetry, but questions remain as to how these variations arose (see the Perspective by Buffett). Monnereau et al. (p. 1014, published online 15 April) modeled grain sizes of crystalline iron—the predicted dominant mineral phase in the core—and found that a… 

The Enigmatic Inner Core

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Dynamic history of the inner core constrained by seismic anisotropy

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Candy Wrapper for the Earth's Inner Core

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Structure and dynamics of Earth's inner core

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An initial map of fine-scale heterogeneity in the Earth’s inner core

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Heterogeneity and Anisotropy of Earth's Inner Core

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It is shown that a single model of thermochemical convection and dynamo action can account for all these effects by producing a large-scale, long-term outer core flow that couples the heterogeneity of the inner core with that of the lower mantle.

Core structure and heterogeneity: a seismological perspective

The aim of this paper is to give an overview of important historical results and review current knowledge of the Earth's core, as well as to discuss prospects for seismological studies of the core.

Growth model of the inner core coupled with the outer core dynamics and the resulting elastic anisotropy

We present a growth tectonic model of Earth's inner core and the resulting model of the seismic anisotropy. The inner core grows anisotropically if the convection in the outer core is of Taylor

Onset and orientation of convection in the inner core

SUMMARY Thermal convection is an effective mechanism for producing seismic anisotropy in many regions of the Earth. However, it is not known whether this mechanism is relevant for the anisotropy

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[1] The structure of the uppermost 100 km of the inner core was examined from PKIKP and PKiKP waveforms in the distance range of 118°–140°. We found evidence of a low-velocity layer in the uppermost

Constraints on upper inner-core structure from waveform inversion of core phases

Summary The determination of the inner-core boundary structure is key to understanding the mechanisms of inner-core growth, iron solidification and anisotropy formation in the inner core. A

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[1] We report complex seismic anisotropy in the top 80 km of the Earth's inner core beneath Africa. The anisotropy in the top 80 km of the inner core is constrained using differential travel times,

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