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Patterson Geophysics has been a leader in exploration techniques in Saskatchewan for over 30 years, including:

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Time-Domain Electromagnetic Surveys including B-field and induction coil.
For investigation of the subsurface at depths that can exceed 1 km, PGI can deploy 3D induction coil (dB/dt) or 3D SQUID (B-field) sensors. Loop sizes can range from 20 to 2000 m, single- or multi-turn, in a variety of configurations (fixed loop, moving loop, in-loop soundings, etc.). Multiple transmit frequencies are available, and customizable time windows and full-wave digital data maximizes the post-processing options. TDEM surveys should be considered for: deep targets, especially where conductive overburden exists; resolution of multiple conductive targets; layered-earth conductivity modelling; excessively cold or dry field conditions.


Frequency-Domain Electromagnetic Surveys, including HLEM (Max-min) and VLF.
To measure conductivities at depths up to 300 m below surface, PGI uses a Slingram-style HLEM (horizontal-loop EM) system with 9 available transmit frequencies ranging from 110 Hz to 28 kHz. PGI also makes use of a VLF (very low frequency) sensor programmed with current VLF transmit frequencies in the 15 to 30 kHz range. Our VLF sensor, in addition to in-phase and out-of-phase (quadrature) measurements, also digitally records field strength and horizontal components. Up to three VLF frequencies can be measured concurrently, and the sensor can be used concurrently with our magnetometers. FDEM methods are useful for situations such as shallow conductive targets, detection of groundwater, mapping of faults and geological boundaries. FDEM methods require only a small survey crew and can be performed year-round, from -30C to +30C.


Underground Electromagnetic surveys. PGI has deployed both TDEM and FDEM surveys in underground mines to successfully map geological changes along mine horizons.

Resistivity and IP

One of the most versatile geophysical techniques, IP (Induced Polarization) and Resistivity surveys can be customized to suit almost any geological setting, and are particularly effective at detecting disseminated mineralization. Resolution of targets ranging from a few meters to a few kilometres in depth and extent can be achieved. PGI uses a multi-channel receiver and high-output transmitter in a variety of array configurations (pole-pole, pole-dipole, gradient, etc.) for efficient electrical imaging of the subsurface.


PGI uses Overhauser and proton-precession magnetometers for fast and effective mapping of magnetic bodies at virtually any scale. Magnetometers can be used in continuous (“walking-mag”) mode and GPS-guided mode if warranted. VLF-EM surveys can be carried out concurrently.

Gridding and Linecutting

PGI field operators are trained in both traditional and modern linecutting methods. “Traditional” linecutting creates straight, accessible survey lines controlled by compass bearing and cut using axes or chainsaws. Traditional lines are up to 1.5 metres in width and can be easily found and accessed for follow-up surveys for several years.
Many modern survey methods can be accomplished via GPS gridding, a low-impact option requiring minimal cutting using axes or machetes. Such lines become overgrown and invisible within a few years. Flagging tape and lake pickets are removed at the end of each survey.


Geophysicists at PGI can help with all aspects of a geophysical survey from survey specifications, grid layout, instrumentation, logistics, data processing, quality control, mapping, plotting, reporting, and interpretation.

Field Camps

PGI specializes in remote, independent, low-impact field camps, deployable virtually anywhere in Canada.
In our field activities, PGI strives to minimize our impact on the environment.
Our field camps use 14 x 16’ tents requiring very little brush clearing. The camps are powered by low-wattage generators, and water is hand-drawn from lakes and rivers. All materials are removed on demobilization, leaving the camp sites as pristine as when we found them.


Our team, in conjunction with Northlands College, the University of Saskatchewan, Black Lake Ventures, and others, has been involved in teaching students about our field techniques and instrumentation for many decades.