TEM — Transient Electromagnetic Sounding

Mapping fault networks, lithological contacts, reservoir beds, and mineralized domains down to depths of 500 m

The deployment of transient electromagnetic fields induced by sudden current shut-off delivers high sensitivity to subsurface conductivity contrasts, enabling high-resolution mapping of deep structural targets without grounded electrodes.

What Subsoil User Challenges Are Solved at the TEM Stage?

Low spatial precision in structural mapping

Applies a methodology with high localization capability and physical sensitivity, enabling the delineation of fault networks, lithological contacts, and orebodies without preliminary drilling.

Operational constraints under difficult surface conditions

Operates without grounded electrodes, deploying seamlessly across any terrain — from marshes and snowbound blocks to exposed bedrock and industrial-impacted sites.

Excessive expenditures of time and financial resources during exploration

High structural resolution allows rapid narrowing of target zones, optimizing downstream drilling volumes and significantly cutting campaign timelines and costs.

Inabilities to effectively resolve deeper subsurface structures

Delivers targeted electromagnetic sounding down to 500 m depths using compact loop configurations — adapted for both regional recon and localized prospect-scale surveys.

How Does the TEM Process Work?

We deploy non-contact pulse electromagnetic profiling technology to investigate subsurface geological structures down to depths of 500 meters.

The execution workflow consists of four structured phases:

Pulse Generation — two ungrounded loops — transmitter and receiver — are deployed on the surface. Pulsing electric current through the transmitter loop induces a transient electromagnetic field that penetrates deep into the subsurface profile;
Signal Recording — the receiving loop captures secondary electromotive force (EMF) signals induced in response to current shut-off. This transient decay response carries diagnostic data on rock conductivity and target anomalies;
Time-Decay Measurement — the induced response is recorded across discrete time channels: early-time measurements resolve shallow strata, while late-time decay samples deeper horizons, providing a continuous vertical conductivity profile;
Data Processing & Interpretation — processing field decay curves yields multi-dimensional geo-electrical cross-sections and 3D inversion models. The method demonstrates high physical sensitivity to fault structures, shear zones, conductive orebodies, and lithological contact boundaries.

The Result: The client receives high-resolution geophysical sections, anomaly maps, and 3D structural models — enabling rapid decision-making, eliminating unnecessary drilling, and maximizing overall campaign efficiency.