Open AccessMantle lateral variations and elastogravitational deformations – I. Numerical modelling
Author(s) -
Métivier L.,
GreffLefftz M.,
Diament M.
Publication year - 2006
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.2006.03159.x
Subject(s) - hydrostatic equilibrium , ellipsoid , geology , compressibility , finite element method , earth model , figure of the earth , deformation (meteorology) , perturbation (astronomy) , mechanics , isotropy , physics , geodesy , geophysics , oceanography , quantum mechanics , thermodynamics
SUMMARY The Earth response (deformation and gravity) to tides or to surface loads is traditionally computed assuming radial symmetry in stratified earth models, at the hydrostatic equilibrium. The present study aims at providing a new earth elastogravitational deformation model which accounts for the whole complexity of a more realistic earth. The model is based on a dynamically consistent equilibrium state which includes lateral variations in density and elastic parameters, and interface topographies. The deviation from the hydrostatic equilibrium has been taken into account as a first‐order perturbation. We use a finite element method (spectral element method) and solve numerically the gravitoelasticity equations. As a validation application, we investigate the deformation of the Earth to surface loads. We first evaluate the classical loading Love numbers with a relative precision of about 0.3 per cent for PREM earth model. Then we assume an ellipsoidal homogeneous incompressible earth with hydrostatic pre‐stresses. We investigate the impact of ellipticity on loading Love numbers analytically and numerically. We validate and discuss our numerical model.