standard Earth model; hydrostatic flattening; inertia coefficient
Abstract :
[en] Modern Earth models are constrained by an inertia coefficient y*=J(2)/H approximate to 0.3308 which leads to a so-called 'hydrostatic' flattening f(hyd) approximate to 1/299.9. The latter is in rather large disagreement with the observed flattening f approximate to 1/298.3. We show that a more satisfactory value of the inertia coefficient for constraining a standard Earth model is y approximate to 0.332, consistent with a hydrostatic flattening of about 1/298.6. The change of the value of the inertia coefficient from about 0.331 to about 0.332 significantly alters the density structure of the core, notably the density jump at the inner core boundary. It brings, as a by-produce, the hydrostatic values of J(2) and H to better agreement with the observed values than is presently thought, and most probably leads for the Slichter mode to a period of much longer than 5.42 h, which is the value computed for PREM.
Disciplines :
Earth sciences & physical geography
Author, co-author :
Denis, Carlo
Rogister, Yves
Amalvict, Martine
Delire, Christine
Denis-Ibrahim, Aysel
Munhoven, Guy ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP) - Pétrologie et géochimie endogènes
Language :
English
Title :
Hydrostatic flattening, core structure, and translational mode of the inner core
Publication date :
1997
Journal title :
Physics of the Earth and Planetary Interiors
ISSN :
0031-9201
Publisher :
Elsevier Science
Volume :
99
Issue :
3-4
Pages :
195-206
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
Communauté française de Belgique : Commissariat Général aux Relations Internationales (CGRI), programme Tournesol
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