Induction loop for mineral exploration

A method comprising:

• providing a plurality of lengths of electrically conductive tubing, each length of electrically conductive tubing being at least partially composed of a first electrically conducting composite material with a specific conductivity higher than aluminum;
• assembling the plurality of lengths of electrically conductive tubing to form a rigid closed electrically conducting loop, the rigid closed electrically conducting loop having a perimeter of 3 meters or more;
• generating an excitation magnetic field by applying an electrical current to the rigid closed electrically conducting loop;
• and
• detecting changes in a volume proximate the rigid closed electrically conducting loop responsive to the excitation magnetic field.

An electromagnetic surveying system comprising:

• a tow assembly connected to an aircraft, the tow assembly comprising:
• a first electrically conducting loop comprising a plurality of lengths of electrically conductive tubing, each length of electrically conductive tubing being at least partially composed of a first electrically conducting composite material with a specific conductivity higher than aluminum, each length of the plurality of lengths of electrically conductive tubing being connected to form a rigid closed loop having a perimeter of 3 meters or more;
• a second electrically conducting loop electrically isolated from the first electrically conducting loop;
• and
• a control module comprising a signal generator in electrical communication with the first electrically conducting loop and configured, during operation of the system, to vary a current in the first electrically conducting loop to periodically apply an excitation magnetic field to a volume proximate to the first electrically conducting loop and to detect, using the second electrically conducting loop, changes in a magnetic field generated by a substance in the volume responsive to the excitation magnetic field.