Is the long-wavelength geoid sensitive to the presence of postperovskite above the core-mantle boundary?

نویسندگان

  • N. Tosi
  • O. Čadek
  • Z. Martinec
  • D. A. Yuen
  • G. Kaufmann
چکیده

[1] The analysis of seismic data represents today the primary tool in the search for the presence of postperovskite in the lowermost mantle (D00). This work aims at testing whether the inversion of gravitational data can also contribute to the detection of postperovskite in D00. We assume that the transition from perovskite to postperovskite is accompanied by a reduction in viscosity and test the effects of such viscosity change on the prediction of the dynamic geoid with a numerical model of subducted lithosphere. Our results show that the long-wavelength component of the geoid is very sensitive to the presence of postperovskite areas in D00, especially if their viscosity is significantly lower than the viscosity of the surrounding perovskite and if these areas are located close to density anomalies, i.e. subducted slabs. Citation: Tosi, N., O. Čadek, Z. Martinec, D. A. Yuen, and G. Kaufmann (2009), Is the longwavelength geoid sensitive to the presence of postperovskite above the core-mantle boundary?, Geophys. Res. Lett., 36, L05303, doi:10.1029/2008GL036902.

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تاریخ انتشار 2009