Dissipation at the core-mantle boundary on a small-scale topography - art. no. B04413 | INSTITUT DE PHYSIQUE DU GLOBE DE PARIS

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  Dissipation at the core-mantle boundary on a small-scale topography - art. no. B04413

Type de publication:

Journal Article

Source:

Journal of Geophysical Research Solid Earth, Volume 111, Ticket B4, p.1-10 (2006)

Numéro d'accès:

0002374133-0001

URL:

http://www.agu.org/journals/jb/

Mots-clés:

Precessing-rigid-body; spheroidal-cavity; earths-core; liquid-; nutation-; flow-; constraints-; torque-; energy-; motion-

Résumé:

<p>The parameters of the nutations are now known with a good accuracy, and the theory accounts for most of their values. Dissipative friction at the core-mantle boundary (CMB) and at the inner core boundary is an important ingredient of the theory. Up to now, viscous coupling at a smooth interface and electromagnetic coupling have been considered. In some cases they appear hardly strong enough to account for the observations. We advocate here that the CMB has a small-scale roughness and estimate the dissipation resulting from the interaction of the fluid core motion with this topography. We conclude that it might be significant.</p>

Notes:

Journal of geophysical research. Série B. Solid earth and planetsInst Phys Globe, Lab Geomagnetisme, F-75252 Paris 05, France; Univ Potsdam, Inst Appl & Ind Math, D-14115 Potsdam, Germany; Inst Phys Globe, Lab Dynam Syst Geol, F-75252 Paris 05, FranceArticleEnglish