Skip to main content

The relative influence of different types of magnetotelluric data on joint inversions

Abstract

Diverse magnetotelluric data (apparent resistivity, phase or geomagnetic transfer function) used during the inversion process provide different information on the model as a consequence of data error. The relative influence of these data constitutes a subject of interest on the inversion process. This influence can be evaluated from the error ratio between two types of data; thus, when phase and the logarithm of apparent resistivity are involved, the well-known ratio of one half is obtained. A new error ratio between the geomagnetic transfer function and the logarithm of apparent resistivity is presented. We deduced this ratio, which is bounded by one half of the amplitude of the geomagnetic transfer function. In order to verify this new ratio, we employed a technique based on the study of the RMS misfit, obtained after an intensive inversion computation whilst taking different error values for the different data. This technique was applied to synthetic and experimental data, and the results agree with the proposed value. This value should be taken into account for setting error floors when performing joint data inversion in order to obtain the same influence from the different data.

References

  • Bendat, J. and A. Piersol, Measurement and Analysis of Random Data, New York, Wiley, 1966.

    Google Scholar 

  • Fischer, G. and B. V. LeQuang, Topography and minimization of the standard deviation in one-dimensional magnetotelluric modeling, Geophys. J. R. astr. Soc., 67, 279–292, 1981.

    Article  Google Scholar 

  • Jones, A. G., The COPROD2 dataset: Tectonic setting, recorded MT data, and comparison of models, J. Geomag. Geoelectr., 45, 933–955, 1993.

    Article  Google Scholar 

  • Ledo, J., A. Gabas, and A. Marcuello, Static shift levelling using geomagnetic transfer functions, Earth Planets Space, 54, 493–498, 2002.

    Article  Google Scholar 

  • Ogawa, Y., Constrained inversion of COPROD-2S2 dataset using model roughness and static shift norm, Earth Planets Space, 51, 1145–1151, 1999.

    Article  Google Scholar 

  • Ogawa, Y., A. G. Jones, M. J. Unsworth, J. R. Booker, X. Lu, J. A. Craven, J. Permelee, and C. Farquharson, Deep electrical conductivity structures of the Appalachian Orogen in the southeastern U.S., Geophys. Res. Lett., 23, 1597–1600, 1996.

    Article  Google Scholar 

  • Siripunvaraporn, W. and G. Egbert, An efficient data subspace inversion method for 2-D magnetotelluric data, Geophysics, 65, 791–803, 2000.

    Article  Google Scholar 

  • Wannamaker, P. E., J. A. Stodt, and L. Rijo, A stable finite element solution for two-dimensional magnetotelluric modeling, Geophys. J. R. astr. Soc., 88, 277–296, 1986.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Anna Gabàs.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Gabàs, A., Marcuello, A. The relative influence of different types of magnetotelluric data on joint inversions. Earth Planet Sp 55, 243–248 (2003). https://doi.org/10.1186/BF03351755

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1186/BF03351755

Key words

  • Magnetotelluric
  • inversion
  • geomagnetic transfer function