SURFACE EM

The general concept of EM is using a source (often a loop of wire, sometimes a dipole) to induce an electromagnetic field in the earth and then measuring that response by separating out the source field (Primary) from the induced field (Secondary)

Transient EM (TEM) prospecting is primarily used for locating massive sulfide ore deposits at great depths. Dias offers industry-leading high-power transmitters, low-noise receivers, and solutions suitable for deep exploration of conductive ore bodies like copper, nickel, uranium, and gold.

Dias has a history of delivering quality, efficient EM surveys. Surveys include SMARTem24 Receivers and proprietary TM-7 SAM Receivers. These instruments are coupled with high-powered Gap Transmitters to produce data with unprecedented signal/noise ratios.

JESSY DEEP HTS & LTS SQUID

• Most sensitive TDEM Sensor high and low temperature SQUID

• High temperature cooled with liquid nitrogen; low temperature cooled with liquid helium

• Direct 1C or 3C B-field measurement at low frequency (0.125 to 5.0 Hz)

• Highest signal-to-noise of any TDEM system in the world allowing for unlimited deep minable detection capability

• Enhanced response from good conductors in the presence of weaker conductive formations and overburden

• Unsurpassed sensitivity and coupled with high power transmitters enables superior survey effectiveness

ADVANTAGES OF SQUID TEM

• Detect deeper conductors

• Greater precision from increased signal to noise results in more precise interpretations and better drill targeting

• Increased discrimination of conductors because of wider bandwidth of B-field response

– Detect basement conductors under conductive cover

– Identify individual conductors within a conductive zone

• Increased signal to noise leads to simplified survey logistics ie: smaller transmitter loop, wider station interval

EQUIPMENT: SENSORS AND SYSTEMS

EM SURVEY MODES

PRODUCTS: INTERPRETATION

EMIT MAXWELL plate modelling

CSIRO inversions

Vpem3D

SimPEG – in development

SQUID vs Coil – SLINGRAM MOVING LOOP

DATA COURTESY OF AREVA RESOURCES CANADA INC.