Frequency Domain Electromagnetics (FDEM)

FDEM is a geophysical technique applicable on soil, rock and paved surfaces to test for bulk ground conductivity, buried metal, lateral changes in soil type or saturation.

Frequency Domain Electromagnetics (FDEM) is applicable on soil, rock, and paved surfaces. It is used to map lateral variations in moisture related to seepage through dams, levees, pipelines, or containment walls. It can also be used to delineate the edges of landfills or to detect buried metal objects such as utilities and underground storage tanks.

How does Frequency Domain Electromagnetic (FDEM) Induction work?

The prospecting equipment consists of a current transmitter with its power supply, a transmitting coil, the receiver of the induced fields and a digital recorder (data logger) of the obtained data, which allows its later study and analysis.

With Frequency Domain Electromagnetics (FDEM), electrical currents are induced into subsurface conductors by an operator-held transmitter loop that radiates an electromagnetic field (EM). As the EM energy encounters different subsurface materials, eddy currents are induced creating secondary electromagnetic fields. This secondary field is recorded at the surface by a receiver loop.

A data logger measures the components of the secondary field that are in-phase with the transmitted EM energy, and that portion which is 90-degrees out of phase (the quadrature component). Under normal subsurface conditions, the in-phase component is strongly affected by the presence of buried metallic objects, while the quadrature component is directly related to terrain conductivity.

Deliverables

Typical deliverables include plan maps of project location and interfering cultural structures, colour-contour maps of metal and earth conductivity responses, and interpretation maps with the cultural responses and subsurface responses clearly separated.

Informative Image displays a topographic colour contour map of a project site. Colour shade from blue to green and to red, with the red areas indicating targeted features identified from the Frequency Domain Electromagnetics (FDEM) geophysics survey performed on the project area.

As your partner in Utility Data Collection and Management, we’ve defined core values that drive our operations and form the basis of everything we do.

30 years industry experience

We’ve achieved a unique position in the marketplace based on decades of experience, which allows us to provide added value to our customers.

Fast flexible mobilization

Our strategic approach to resourcing fosters scalability, flexibility, and rapid response times. We’re here to support you 24/7, and no project is too complex.

Dedicated to training & safety

We foster a culture of continuous improvement through comprehensive internal and external training. Our Health & Safety culture is backed by our HS&E Manual.

Commitment to quality

We’re guided by our Quality Management System (QMS) and our team of experts executes all processes with the highest regard for quality.

Qualified, dedicated partners in Damage Prevention.

A full suite of Utility Locating services backed by a focus on Safety, Quality and Customer Excellence.