Investigation of MT static shift correction methods

Ben K Sternberg, James Washburne, Robert G. Anderson

Research output: Contribution to conferencePaper

12 Citations (Scopus)

Abstract

Very small scale inhomogeneities (that is, with dimensions much less than a skin depth at the highest recorded frequency) can lead to severe problems in the interpretation of magnetotelluric (MT) data. These small-scale inhomogeneities can produce a shift of the MT apparent resistivity sounding curve such that the shifted curve is parallel to the undistorted curve on a log apparent resistivity versus log frequency plot. This parallel shift is commonly referred to as a static shift. The amount of static shift of the MT curves cannot be determined directly from conventionally recorded MT data. The most practical method for measuring the static shift appears to be a controlled-source measurement of the magnetic field, since magnetic fields, unlike electric field measurements, will be relatively unaffected by small scale inhomogeneities. The relative strengths and weaknesses of a number of magnetic field controlled-source methods are compared for this application, including central-loop frequency-domain sounding, central loop time-domain sounding, and far-field loop-loop sounding. The controlled-source sounding (which may be a relatively shallow sounding and made with lightweight equipment) can be combined in a joint inversion with a deep MT sounding to obtain a complete, undistorted model of the earth.

Original languageEnglish (US)
Pages264-267
Number of pages4
StatePublished - Jan 1 1985
Externally publishedYes
Event1985 Society of Exploration Geophysicists Annual Meeting, SEG 1985 - Washington, United States
Duration: Oct 6 1985Oct 10 1985

Conference

Conference1985 Society of Exploration Geophysicists Annual Meeting, SEG 1985
CountryUnited States
CityWashington
Period10/6/8510/10/85

Fingerprint

sounding
inhomogeneity
magnetic field
electrical resistivity
shift
curves
electric field
skin
magnetic fields
method
far fields
plots
inversions
electric fields

ASJC Scopus subject areas

  • Geophysics

Cite this

Sternberg, B. K., Washburne, J., & Anderson, R. G. (1985). Investigation of MT static shift correction methods. 264-267. Paper presented at 1985 Society of Exploration Geophysicists Annual Meeting, SEG 1985, Washington, United States.

Investigation of MT static shift correction methods. / Sternberg, Ben K; Washburne, James; Anderson, Robert G.

1985. 264-267 Paper presented at 1985 Society of Exploration Geophysicists Annual Meeting, SEG 1985, Washington, United States.

Research output: Contribution to conferencePaper

Sternberg, BK, Washburne, J & Anderson, RG 1985, 'Investigation of MT static shift correction methods' Paper presented at 1985 Society of Exploration Geophysicists Annual Meeting, SEG 1985, Washington, United States, 10/6/85 - 10/10/85, pp. 264-267.
Sternberg BK, Washburne J, Anderson RG. Investigation of MT static shift correction methods. 1985. Paper presented at 1985 Society of Exploration Geophysicists Annual Meeting, SEG 1985, Washington, United States.
Sternberg, Ben K ; Washburne, James ; Anderson, Robert G. / Investigation of MT static shift correction methods. Paper presented at 1985 Society of Exploration Geophysicists Annual Meeting, SEG 1985, Washington, United States.4 p.
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