Features of transient electromagnetic (tem) devices
The instruments used to take these measurements will include a transmitter, as well as a wire or coil that is used to transmit the pulses. They will also have an antenna or a receiver coil and a receiver instrument that can take the recordings. Depending on the power of the machine used, it is possible to get readings that are just a few meters below the earth’s surface to those that can measure hundreds of meters down.
The low power options that will measure just a few meters down are small and portable, and you can even operate them on C batteries. There are somewhat larger systems available, too, which use auto batteries to work. Those who find they need a more powerful system will need to have a generator that can supply them with the power they require.
How transient electromagnetic (tem) devices work
The instruments used to make these measurements rely on Lenz’s Law and Faraday’s Law of Induction. The probes are inserted into the ground and they are then energized by a current. This current is then cut off, and measurements are taken to determine how long it takes for the current to dissipate. When this happens, there is a change in the electromagnetic field, and this causes what are known as eddy currents. Eventually, they will subside. The information gleaned from these tests can give the user a better understanding of what is contained in the ground below.
About transient electromagnetic (tem) devices
Time domain electromagnetics, or TDEM, is also known as transient electromagnetics. This is a technique used to explore the earth’s surface to determine not only the electrical properties, but also certain magnetic properties. TDEM is applied to many different fields today including exploration for groundwater, environmental mapping, mineral exploration and mining, and oil and gas exploration.
Some of the manufacturers making these devices today include Crone, Geonics Limited, and GF Instruments. With the various options available, you should be capable of finding one or more of these devices to help you with your work whether you are operating on a large or small scale.