HR: 0800h
AN: G51A-0806 [Abstracts]
TI: Gravimetry And Internal Structure Of Terrestrial Planets
AU: * Couturier, F
EM: francois.couturier@univ-nantes.fr
AF: Laboratoire de Planetologie et Geodynamique, 2 rue de la Houssiniere, NANTES, 44300
France
AU: Dumoulin, C
EM: caroline.dumoulin@univ-nantes.fr
AF: Laboratoire de Planetologie et Geodynamique, 2 rue de la Houssiniere, NANTES, 44300
France
AU: Cadek, O
EM: oc@karel.troja.mff.cuni.cz
AF: Department of Geophysics, Faculty of Mathematics and Physics, Charles University, V Holesovickach 2,
PRAGUE, 180 00
Czech Republic
AU: Choblet, G
EM: gael.choblet@univ-nantes.fr
AF: Laboratoire de Planetologie et Geodynamique, 2 rue de la Houssiniere, NANTES, 44300
France
AU: SOTIN, C
EM: christophe.sotin@univ-nantes.fr
AF: Laboratoire de Planetologie et Geodynamique, 2 rue de la Houssiniere, NANTES, 44300
France
AB:
Several present day numerical tools provide thermal convection models in 3D spherical shells, taking into account the large
viscosity gradients due to temperature variations. In addition, spectral methods allow the computation of dynamic topography
and geoid for a medium with such a variable viscosity. In the present study, we combine both simulation tools in order to
better understand the relationship between internal dynamics and surface gravimetry of terrestrial planets. The pressure
gradient and temperature fields obtained from a 3D convection model (cubed sphere gridding technique, multigrid flow solver)
are used as inputs for the calculation of dynamic topography and gravity anomalies. As a start, we will show the gravimetric
and topographic signatures of synthetic models for several convective regimes depending on the viscosity law (isoviscous
case, stagnant lid), heating conditions (from below, from within) and Rayleigh number (number of plumes, time-dependency).
A comparison between Mars Global Surveyor data and these simple synthetic results will be proposed in order to reinterpret
some of the large scale gravity potential and topographic features. In the future, more complex simulations will be performed
(e.g., taking into account a more realistic rheology).
DE: 1200 GEODESY AND GRAVITY
DE: 1294 Instruments and techniques
DE: 5494 Instruments and techniques
SC: Geodesy [G]
MN: Fall Meeting 2005