GEM-3 Data Examples
The GEM-3 quadrature components are relatively immune to magnetic soils or rocks. A sum of all quadrature components (the optional audio is based on this sum), therefore, is an excellent detection indicator. This fact renders the sum of all quadrature components an excellent detector, particularly in a magnetic geology - Metal Detection in Magnetic Geology
For discrimination, characterization, or identification using the broadband GEM data, please go to Electromagnetic Induction Spectroscopy (EMIS).
Fig 1. Sum of all 10-freq quadrature data in UXO Survey in Midwest. The quadrature data are relatively insensitive to the magnetic field variation, which make them an excellent detector.
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| Fig 2 (Top). This representation is based on the sum of the incremental quadrature differences (absolute value). A UXO survey in Alabama. | ||
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Fig 3 (Right). GEM-3 survey on a Hawaiian Island |
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Geophex has a UXO test site a 10m x 10m plot in an urban area containing 21 ferrous and nonferrous metal objects listed in the table. The site also contains a basketball-sized diabase boulder, a magnetic rock. All targets are buried in the native clay soil. For details, see Geophex UXO Test Site.
For GEM-3 performance in magnetic environments, GEM-3 Survey in Magnetic Geology.
For discrimination data, please go to Electromagnetic Induction Spectroscopy (EMIS).
