Journal cover Journal topic
Solid Earth An interactive open-access journal of the European Geosciences Union

Journal metrics

  • IF value: 3.495 IF 3.495
  • IF 5-year<br/> value: 3.386 IF 5-year
    3.386
  • CiteScore<br/> value: 3.70 CiteScore
    3.70
  • SNIP value: 0.783 SNIP 0.783
  • SJR value: 1.039 SJR 1.039
  • IPP value: 1.987 IPP 1.987
  • h5-index value: 20 h5-index 20
https://doi.org/10.5194/sed-7-3817-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
15 Dec 2015
Review status
This discussion paper has been under review for the journal Solid Earth (SE). The revised manuscript was not accepted.
A simple 3-D numerical model of thermal convection in Earth's growing inner core: on the possibility of the formation of the degree-one structure with lateral viscosity variations
M. Yoshida Department of Deep Earth Structure and Dynamics Research, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2–15 Natsushima-cho, Yokosuka, Kanagawa 237-0061, Japan
Abstract. An east-west hemispherically asymmetric structure for Earth's inner core has been suggested by various seismological evidence, but its origin is not clearly understood. Here, to investigate the possibility of an "endogenic origin" for the degree-one thermal/mechanical structure of the inner core, I performed new numerical simulations of thermal convection in the growing inner core. A setup value that controls the viscosity contrast between the inner core boundary and the interior of the inner core, ΔηT, was taken as a free parameter. Results show that the degree-one structure only appeared for a limited range of ΔηT; such a scenario may be possible but is not considered probable for the real Earth. The degree-one structure may have been realized by an "exogenous factor" due to the planetary-scale thermal coupling among the lower mantle, the outer core, and the inner core, not by an endogenic factor due to the internal rheological heterogeneity.

Citation: Yoshida, M.: A simple 3-D numerical model of thermal convection in Earth's growing inner core: on the possibility of the formation of the degree-one structure with lateral viscosity variations, Solid Earth Discuss., 7, 3817-3841, https://doi.org/10.5194/sed-7-3817-2015, 2015.
M. Yoshida
M. Yoshida

Viewed

Total article views: 356 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
268 77 11 356 3 6

Views and downloads (calculated since 15 Dec 2015)

Cumulative views and downloads (calculated since 15 Dec 2015)

Saved

Discussed

Latest update: 21 Jul 2017
Publications Copernicus
Download
Short summary
An east–west hemispherically asymmetric structure for Earth’s inner core has been suggested by various seismological evidence, but its origin is not clearly understood. Here, to investigate the possibility of an “endogenic origin” for the degree-one thermal/mechanical structure of the inner core, I performed new numerical simulations of thermal convection in the growing inner core. Results show that the degree-one structure may have been realized by an “exogenous factor”.
An east–west hemispherically asymmetric structure for Earth’s inner core has been suggested...
Share