How magnetotellurics is able to see through 3D near-surface inhomogeneities?

L. Szarka, D. Zhang, A. Ádám

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

In order to investigate imaging properties of various magnetotelluric interpretation parameters over complicated models, we carried out numerical model calculations, where the models contained a 3D near-surface ("shallow") part and a 3D or 2D deep part. Various alternatively defined magnetotelluric responses, all of them based on rotational invariants of the magnetotelluric impedance tensor were considered. Then we calculated correlation coefficients between all these MT responses, and the characteristic geometrical parameters of the subsurface models, considered as a composition of " shallow+deep" elements. A systematic behaviour, similar to that had been observed in 1D situation was found: det(ReZ), Re det(Z) based apparent resistivity has the largest depth of investigation and the best lateral resolution. Furthermore, besides the phase, the Re det(Z) (a twin-parameter of the phase) seems to give the most direct response about deep structures. In presence of 3D near-surface inhomogeneities the most surprising result is that there are narrow period windows, where the deep model can be directly seen in the Re det(Z) and in the phase responses.

Original languageEnglish
Pages (from-to)381-394
Number of pages14
JournalActa Geodaetica et Geophysica Hungarica
Volume39
Issue number4
DOIs
Publication statusPublished - 2004

Fingerprint

Magnetotellurics
inhomogeneity
phase response
Tensors
Numerical models
electrical resistivity
correlation coefficients
Imaging techniques
impedance
tensors
Chemical analysis
parameter

Keywords

  • Correlation
  • Magnetotellurics
  • Numerical modelling
  • Rotational invariants

ASJC Scopus subject areas

  • Building and Construction
  • Geology

Cite this

How magnetotellurics is able to see through 3D near-surface inhomogeneities? / Szarka, L.; Zhang, D.; Ádám, A.

In: Acta Geodaetica et Geophysica Hungarica, Vol. 39, No. 4, 2004, p. 381-394.

Research output: Contribution to journalArticle

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