Technical Notes - Helicopter Electromagnetics

Fugro Standard Conductor Interpretations

S: Flat lying conductors - generally surficial. Typical geologic anomalies might be conductive overburden, swamps or clay layers. They would not appear to be conductive at depth.

L: Line current - an anomaly with the shape typical of line currents - typically cultural (human source) such as power lines, train tracks, fences, etc.

D: Dike - an anomaly whose shape matches that of a steeply dipping thin dike-like conductor. The thickness appears to be less than about 3m. These are commonly conductors in steeply-dipping geology, but may also be conductive shear zones.

B: Bedrock - an anomaly whose response matches that of a bedrock conductor, but not thin and / or near vertical. This anomaly type might include other shapes of conductors: roughly pod-shaped, thick dikes, short strike-length bodies, or conductors sub-parallel to the flight path.

Greg Hodges, Chief Geophysicist, 2001