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The Effects of Negative Values of Apparent Resistivity in TEM Surveys
Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de Sao Paulo (USP), Sao Paulo, Brasil
Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de Sao Paulo (USP), Sao Paulo, Brasil
Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de Sao Paulo (USP), Sao Paulo, Brasil
Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de Sao Paulo (USP), Sao Paulo, Brasil
University of Lisboa, Don Luiz Institute (IDL), Lisbon, Portugal
Brazilian Geological Survey (CPRM), Belo Horizonte, Brazil
- 1 Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de Sao Paulo (USP), Sao Paulo, Brasil
- 2 Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de Sao Paulo (USP), Sao Paulo, Brasil
- 3 Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de Sao Paulo (USP), Sao Paulo, Brasil
- 4 Departamento de Geofísica, Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG), Universidade de Sao Paulo (USP), Sao Paulo, Brasil
- 5 University of Lisboa, Don Luiz Institute (IDL), Lisbon, Portugal
- 6 Brazilian Geological Survey (CPRM), Belo Horizonte, Brazil
International Journal of Geosciences·Volume 07 (2016)·Pages 1182–1190·Published 19 October 2016·DOI10.4236/ijg.2016.710088
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Abstract
The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, intuitive and enable an initial interpretation of the results. On the other hand, in TEM method the apparent resistivity values are not very intuitive and interpretation based only on the apparent resistivity values cannot be done reasonably. In this way, this paper presents a discussion about the reasons and effects of the negatives values of apparent resistivity in TEM soundings. The main objective of this paper is to clarify the meanings of these negatives values and the possible effects in TEM inversion.
KeywordsTransient Electromagnetic (TEM)Apparent ResistivityNegative Values
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