Melting of the Earth’s inner core

  title={Melting of the Earth’s inner core},
  author={David Gubbins and Binod Sreenivasan and Jon E. Mound and Sebastian 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… 
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
Regional stratification at the top of Earth's core due to core–mantle boundary heat flux variations
Earth’s magnetic field is generated by turbulent motion in its fluid outer core. Although the bulk of the outer core is vigorously convecting and well mixed, some seismic, geomagnetic and geodynamic
Earth science: A deep foundry
Geodynamo simulations showing that variations in heat flow at the core–mantle boundary are transferred to the inner core boundary are presented, finding that the variations can be large enough to cause heat to flow into the inner cores and, if this were to occur in the Earth, to cause localized melting.
Melting of Iron at Earth’s Inner Core Boundary Based on Fast X-ray Diffraction
Hot Enough to Melt Iron Earth's core is divided into a fluid outer core and a solid inner core, both composed predominately of iron at extremely high pressures and temperatures. The boundary between
Earth’s solid inner core: Seismic implications of freezing and melting
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
Mantle-induced temperature anomalies do not reach the inner core boundary
  • C. Davies, J. Mound
  • Environmental Science, Physics
    Geophysical Journal International
  • 2019
Temperature anomalies in Earth’s liquid core reflect the vigour of convection and the nature and extent of thermal core–mantle coupling. Numerical simulations suggest that longitudinal temperature
Bottom-up control of geomagnetic secular variation by the Earth’s inner core
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.


Melting-induced stratification above the Earth’s inner core due to convective translation
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.
The role of the Earth's mantle in controlling the frequency of geomagnetic reversals
A series of computer simulations of the Earth's dynamo illustrates how the thermal structure of the lowermost mantle might affect convection and magnetic-field generation in the fluid core. Eight
Dynamos with weakly convecting outer layers: implications for core-mantle boundary interaction
Convection in the Earth's core is driven much harder at the bottom than the top. This is partly because the adiabatic gradient steepens towards the top, partly because the spherical geometry means
Lopsided Growth of Earth's Inner Core
It is proposed that the growth of the solid core implies an eastward drift of the material, driven by crystallization in the Western Hemisphere and melting in the Eastern Hemisphere, which generates an asymmetric distribution of sizes of iron crystals, which grow during their translation.
Outer-core compositional stratification from observed core wave speed profiles
Light elements must be present in the nearly pure iron core of the Earth to match the remotely observed properties of the outer and inner cores. Crystallization of the inner core excludes light
Stratification of the top of the core due to chemical interactions with the mantle
[1] Chemical interactions between the core and the mantle have been proposed as a mechanism to transfer O and Si to the core. Adding light elements to the top of the core creates a stratified layer,
Scale disparities and magnetohydrodynamics in the Earth's core
  • Keke Zhang, D. Gubbins
  • Physics
    Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
  • 2000
Fluid motions driven by convection in the Earth's fluid core sustain geomagnetic fields by magnetohydrodynamic dynamo processes. The dynamics of the core is critically influenced by the combined