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arXiv · 0707.0638

Core-mantle boundary deformations and J2 variations resulting from the 2004 Sumatra earthquake

V. Cannelli·D. Melini·P. De Michelis·A. Piersanti·F. Florindo
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Abstract

The deformation at the core-mantle boundary produced by the 2004 Sumatra earthquake is investigated by means of a semi-analytic theoretical model of global coseismic and postseismic deformation, predicting a millimetric coseismic perturbation over a large portion of the core-mantle boundary. Spectral features of such deformations are analysed and discussed. The time-dependent postseismic evolution of the elliptical part of the gravity field (J2) is also computed for different asthenosphere viscosity models. Our results show that, for asthenospheric viscosities smaller than 10^18 Pa s, the postseismic J2 variation in the next years is expected to leave a detectable signal in geodetic observations.

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V. Cannelli, D. Melini, P. De Michelis, A. Piersanti, F. Florindo. 2007-07-04. Core-mantle boundary deformations and J2 variations resulting from the 2004 Sumatra earthquake. https://doi.org/10.1111/j.1365-246x.2007.03443.x

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