Melting of the Earth’s inner core

  title={Melting of the Earth’s inner core},
  author={D. Gubbins and B. Sreenivasan and J. Mound and S. Rost},
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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It is shown that this layer can be generated by simultaneous crystallization and melting at the surface of the Earth’s inner core, and that a translational mode of thermal convection in the inner core can produce enough melting and crystallization on each hemisphere respectively for the dense layer to develop. Expand
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