Melting of the Earth’s inner core

@article{Gubbins2011MeltingOT,
  title={Melting of the Earth’s inner core},
  author={D. Gubbins and B. Sreenivasan and J. Mound and S. Rost},
  journal={Nature},
  year={2011},
  volume={473},
  pages={361-363}
}
The Earth’s magnetic field is generated by a dynamo in the liquid iron core, which convects in response to cooling of the overlying rocky mantle. The core freezes from the innermost surface outward, growing the solid inner core and releasing light elements that drive compositional convection. Mantle convection extracts heat from the core at a rate that has enormous lateral variations. Here we use geodynamo simulations to show that these variations are transferred to the inner-core boundary and… Expand
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To match the observed pattern of geomagnetic secular variation, the solid material forming the inner core must now be in a state of differential growth rather than one of growth and melting induced by convective translation. Expand
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