Looking Inside the Earth
, Electromagnetic Surveys
• Electromagnetic surveys work like transformers, as follows:
Alternating current is passed through the primary, transmitting coil.
A magnetic field is induced which spreads into the ground.
The magnetic field induces a secondary current in any underground
material which acts as a conductor, eg: water/iron-bearing minerals.
The current sets up an alternating secondary magnetic field.
This field is detected by the secondary, receiving coil and the
information is sent to a data logger.
, Electromagnetic Surveys
• Electromagnetic surveys work like transformers, as follows:
Alternating current is passed through the primary, transmitting coil.
A magnetic field is induced which spreads into the ground.
The magnetic field induces a secondary current in any underground
material which acts as a conductor, eg: water/iron-bearing minerals.
The current sets up an alternating secondary magnetic field.
This field is detected by the secondary, receiving coil and the
information is sent to a data logger.
