Very Low Frequency (VLF) Electromagnetics 

Very low frequency (VLF) surveys measure components of the electromagnetic field within the range of 15-30 kHz that are propagated by government / military stations scattered around the globe.  By utilising these low frequency fields long, linear conductors produce localised anomalies, making VLF surveys a robust tool for mapping geological structure.  For mineral exploration, this includes the mapping of conductive fault / fracture zones, the apparent dip of fault and shear zones and the identification of conductive ground potentially corresponding to sulphide concentrations.  Data can also be used to map overburden or detect conductive water-bearing fractures, or for groundwater contaminant mapping.