Core processes

  • Article
    | Open Access

    Through platinum metal-silicate partitioning coefficient measurements, the authors here show that platinum partitioning into metal is lowered at high pressure–temperature conditions. This finding implies that the Earth’s mantle was likely enriched in platinum immediately following the core-mantle differentiation.

    • Terry-Ann Suer
    • , Julien Siebert
    •  & Guillaume Fiquet
  • Article
    | Open Access

    This study describes how the geomagnetic axial dipole dominance of Earth’s magnetic field remained stable through large parts of the geological time. Since other characteristics of the geomagnetic field have changed substantially on the same timescales, this new observation provides a challenge for future core modeling studies.

    • Andrew J. Biggin
    • , Richard K. Bono
    •  & Pavel V. Doubrovine
  • Article
    | Open Access

    Thermal conductivity of Earth’s core affects Earth’s thermal structure, evolution and dynamics. Based on thermal conductivity measurements of iron–silicon alloys at high pressure and temperature conditions, the authors here propose Earth’s inner core could be older than previously expected.

    • Wen-Pin Hsieh
    • , Alexander F. Goncharov
    •  & Jung-Fu Lin
  • Article
    | Open Access

    Cooling of the iron core in the early Earth may have been too slow to allow for the generation of a magnetic field. Based on quantum mechanical and geodynamical modelling approaches, the authors find that the electrical conductivity of silicate liquid at high pressure and temperature conditions could have been sufficient to generate a silicate dynamo and a magnetic field in the early Earth.

    • Lars Stixrude
    • , Roberto Scipioni
    •  & Michael P. Desjarlais
  • Article
    | Open Access

    The inner core of the Earth is formed of a crystalline solid which is mostly composed of iron. Here, the authors use molecular dynamics methods to show that the crystalline structure of the inner core may have a viscosity close to that of liquid iron, despite being a solid.

    • Anatoly B. Belonoshko
    • , Jie Fu
    •  & Maurizio Mattesini
  • Article
    | Open Access

    A new regime of planetary magnetic fields was revealed through the MESSENGER spacecraft mission to Mercury. Here, the authors present a numerical dynamo model that can re-produce both the axisymmetric and anomalously axially offset dipolar magnetic field of Mercury.

    • Futoshi Takahashi
    • , Hisayoshi Shimizu
    •  & Hideo Tsunakawa
  • Article
    | Open Access

    During planetary formation segregation of an iron core from rocky silicates takes place. Here, the authors use analogue fluid experiments show that iron diapirs entrain volatiles and silicates to the Earth’s core and initiate buoyant thermochemical plumes to reoxidize and hydrate the upper mantle and atmosphere.

    • J. R. Fleck
    • , C. L. Rains
    •  & P. L. Olson
  • Article
    | Open Access

    The existence of a mushy zone in the Earth’s inner core has been suggested, but has remained unproven. Here, the authors have discovered a 4–8 km thick mushy zone at the inner core boundary beneath the Okhotsk Sea, indicating that there may be more localized mushy zones at the inner core boundary.

    • Dongdong Tian
    •  & Lianxing Wen
  • Article
    | Open Access

    The detection of Earth’s anti neutrino emission from potassium and the mantle remain elusive. Here the authors propose a method for measuring potassium and mantle geo-neutrinos by detecting their elastic scattering on electrons with direction-sensitive detectors.

    • Michael Leyton
    • , Stephen Dye
    •  & Jocelyn Monroe
  • Article
    | Open Access

    Rapid and spatially localized geomagnetic field variations around 1000 BC are hard to reconcile with expected field behaviour arising from the core dynamo. Here, the authors show that the intensity spike is consistent with an intense flux patch on the core-mantle boundary (8–22°) located under Saudi Arabia.

    • Christopher Davies
    •  & Catherine Constable
  • Article
    | Open Access

    Terrestrial basalts have a unique iron isotopic signature taken as fingerprints of core formation. Here, high pressure studies show that force constants of iron bonds increase with pressure similarly for silicate and metals suggesting interplanetary isotopic variability is not due to core formation.

    • Jin Liu
    • , Nicolas Dauphas
    •  & Jung-Fu Lin
  • Article
    | Open Access

    The Earth’s core has lower density than pure iron and many studies have looked into which light elements may be present. The authors here carry outin situhigh pressure and temperature neutron experiments indicating that hydrogen may have been the first light element to dissolve into the iron core.

    • Riko Iizuka-Oku
    • , Takehiko Yagi
    •  & Asami Sano-Furukawa
  • Article
    | Open Access

    The composition of the Earth's core, particularly the light elements present, is not well constrained. Here, the authors report sound velocities of liquid iron-carbon alloy as measured at very high pressures using inelastic X-ray scattering and suggest that carbon cannot be predominant in the outer core.

    • Yoichi Nakajima
    • , Saori Imada
    •  & Alfred Q. R. Baron