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Two Approaches to the Solution of Inversion Problem in the Bear Experiment

  • A. A. ZhamaletdinovEmail author
  • M. S. Petrishchev
  • V. Yu. Semenov
Conference paper
Part of the Springer Proceedings in Earth and Environmental Sciences book series (SPEES)

Abstract

There is completed the interpretation of the results of the BEAR experiment on synchronous magnetotelluric sounding of the lithosphere of the Fennoscandian Shield on the network of 150 × 150 km. The experiment has been made 20 years ago, in 1998, but till that time no common decision on the deep structure of lithosphere is achieved because of super complicated primary data. Two possible approaches to the solution of the problem are applied in the article. The first approach, purely formal. It applies to the OCCAM inversion technique. The approache is based on the phase values of the impedance with reference to the global magnetovariational sounding. The second is phenomenological approach. It is based on the use of a priori information, which makes it possible to regularize the solution of the inverse one-dimensional problem. Based on the results of phenomenological processing, a quasi-three-dimensional model of the electrical conductivity of the lithosphere is constructed. There are detected two anomalies of reduced resistivity are established in the interval of depths of 30–60 km that spatially coinciding with the regions of the Moho boundary submerging up to 55–60 km.

Keywords

Fennoscandian shield Magnetotelluric sounding Lithosphere Occam inversion Phenomenological interpretation 

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • A. A. Zhamaletdinov
    • 1
    • 2
    Email author
  • M. S. Petrishchev
    • 1
  • V. Yu. Semenov
    • 3
  1. 1.St. Petersburg Branch of Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of the Russian Academy of SciencesSt. PetersburgRussia
  2. 2.Geological Institute of the Kola Science Center of the Russian Academy of SciencesApatityRussia
  3. 3.Geophysical Institute of the Polish Academy of SciencesWarsawPoland

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