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Study and Detection on the Geodynamic Effects of the Earth's Fluid Outer Core
Received date: 2002-12-02
Online published: 2003-03-10
Supported by
supported by the NNSF (40174022 and 49925411)) and Chinese Academy of Sciences (KZCX2-106)
The long-term, continuous gravity data, recorded with superconducting gravimeters (SCG) at the Global Geodynamics Project (GGP) observatories including one at Wuhan, and the corresponding station atmospheric pressure records have been comprehensively processed and analyzed in order to study and detect the geodynamical effects of the Earth's fluid outer core (FOC). The elasto-gravitational deformation responses of the Earth to thesolar-luni tidal forces, surface tractions and the perturbations of the pressure and gravity on the core-mantle boundary (CMB) and the solid inner core boundary (ICB) due to the dynamical behaviors of the FOC, are systematically discussed. Based on the resonance enhancement in diurnal tidal gravity observations, the Earth's free core nutation (FCN) is studied by stacking the tidal gravity data obtained with the international SCG. As a result, the FCN parameters are determined accurately. The free oscillations of the FOC are theoretically investigated by using a variational approach of the displacement field. And the corresponding eigenvalue-eigenvector problem for the finite element computation is deduced. By simultaneouslyusing the long-term, continuous and high-quality gravity data observed with the SCG at the GGP observatories, the translational oscillations of the solid inner core is studied.
XU Jian-Qiao , SUN He-Ping . Study and Detection on the Geodynamic Effects of the Earth's Fluid Outer Core[J]. Journal of University of Chinese Academy of Sciences, 2003 , 20(2) : 247 -253 . DOI: 10.7523/j.issn.2095-6134.2003.2.021
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