Airborne EM Interpretation

CDI Conductivity Depth Imaging

A wide variety of new airborne electromagnetic systems are available for mineral exploration and geo-technical studies. Each design has its particular strengths and may be particularly well suited to one geologic environment or objective and be unsuited to another.

Scott Hogg has developed both frequency and time domain systems, including the first helicopter towed transient system at Aerodat in 1989. Scott Hogg & Associates can provide an independent source of airborne electromagnetic expertise; in theory, equipment, operations and interpretation.

Now providing CDI Conductivity Depth Imaging services with EMFLOW

EMFLOW is an electromagnetic analysis tool from Encom Technology that can work with both frequency and time domain systems. The process transforms the measured EM signals into timeconstant or Tau domain.

The process takes into account the transmitted waveform and receiver response characteristics as well as the Transmitter-Receiver geometries. This de-convolved data is used to create a Conductivity Depth Image that can be a very effective analysis tool, particularly for shallow dipping conductors.

The example presented below utilises Aeroquest AeroTEM data, courtesy of Great Northern Mining and Exploration Inc. The Tz-Rz response profiles are presented in the top pannel with a logarithmic vertical scale, and a total magnetic field profile is displayed in the centre.  The corresponding CDI section is shown at the bottom.  The vertical axis is height above sea level and the yellow to red colours are associated with higher conductivity.