VLF GROUND SURVEYS, A POWERFUL TOOL FOR THE STUDY OF SHALLOW TWO-DIMENSIONAL STRUCTURES
ISSN: |
1365-2478
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Source: |
Blackwell Publishing Journal Backfiles 1879-2005
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Topics: |
Geosciences
Physics
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Notes: |
The suitability of VLF ground surveys in the investigation of shallow two-dimensional structures is analyzed. For such structures the polar formalism is derived, necessary in practice since the transmitters are generally not in the structural strike or profile. A simple vertical dike is considered to demonstrate the striking anisotropy which can be expected over such a structure, in particular the high apparent resistivity along the direction of a well-conducting dike and the low resistivity across it. The theory is then confronted with the practical example of an asymmetrical vertical dike resulting from a strike-slip fault. Modelling of the survey results is very successful and yields good confirmation of the polar behaviour. VLF ground surveys thus provide a quick and powerful tool for the study of geological accidents within about 100 m of the surface.
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Type of Medium: |
Electronic Resource
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URL: |