Spectral IP and Resistivity

Spectral Induced Polarization & Resistivity surveys (IP & Res) are excellent methods for detecting disseminated sulphide mineralization that could be associated with gold. The surveys are carried out using surface and borehole modes.

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Large Loop TDEM

ClearView Geophysics Inc. owns and operates transient PROTEM receivers and TEM57/67 transmitters built by Geonics. This system has proven itself useful for detecting both good and bad conductor sulphide mineralization located both shallow and 100’s of metres deep.  It is also useful for detecting sources of water.

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Snowmobile-Mode Cesium Magnetics and more...

Cesium magnetometer and other geophysical surveys are carried out using custom-built sleighs, carts or rafts pulled behind standard snowmobiles, ATVs and boats.  The snowmobile-mode cesium magnetics system has proven itself on numerous large-scale mineral exploration projects during the past 25+ years. 

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Seismic Refraction

Seismic Refraction surveys are typically carried out for depth to bedrock investigations.  The "shot" can be either an explosive or hammer source.  Interpex IXRefraX software is used to process the data.

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Electromagnetic (EM) and Magnetic surveys

EM and Magnetic surveys are perhaps the most common geophysical methods used on mineral exploration and environmental investigations. The most commonly used EM instruments for environmental investigations are the Geonics EM31 and EM61.

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GPR ( Ground Penetrating Radar )

GPR works best in low conductivity areas. Conductive materials (e.g., clay) attenuate the GPR signal to the point that very little depth penetration is achieved. Penetration is greatest in unsaturated sands and fine gravels.

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Gravity

Gravity surveys are completed for a number or applications, including mineral exploration (e.g., diamonds) and geotechnical investigations (e.g., escarpments).

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Geophysical Interpretation

ClearView has extensive experience interpreting airborne and ground-based geophysical data. We use UBC's suite of inversion software to produce 2D and 3D interpretations of total field magnetics and IP/Resistivity data. Post-processing software is also used to produce various derivative datasets and maps.  

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Welcome to ClearView Geophysics

ClearView Geophysics Inc. is a geophysical services company founded in 1996.  There is no better way to collect high resolution sub-surface data than with ground-based sensors or 'boots on the ground'. When you describe your project goals to us, we will design a geophysical survey to help you achieve those goals in the most cost-effective manner possible. Getting high resolution ground-based geophysical data is arduous but worth it - so we are constantly working to find ways to make it easier, such as with our snowmobile/ATV/boat-mode surveys.

Joe Mihelcic, B.Sc.(Hon), P.Eng.(ON/NB/NL), P.Geo. (NU/NT/NS/NL), M.B.A.; other jurisdictions licensed and authorized as required.
Geophysicist, President & Owner

About the Owner: Mr. Mihelcic is an Applied Science '88 Geological Engineering (Geophysics Option) graduate of Queen's University at Kingston and '95 MBA graduate of Ivey Business School at the University of Western Ontario in London. He enjoys designing and implementing off-the-shelf components and technologies to make ground geophysical surveys easier and therefore more cost effective. He also writes C++ software to streamline processing and interpretation.

CSAMT Surveys for Gold...not just epithermal

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CSAMT (Controlled Source Audio-frequency Magnetotellurics) are an effective way to image the ground resistivity by collecting 'soundings' at each location.  Readings taken in the 'Scalar-Mode' use one magnetic sensor which is oriented perpendicular to several 25-metre or 50-metre electrical dipoles.  A transmitter located several km away produces frequencies that range from 9600 Hz to as low as 1 Hz. Please checkout this case history comparing inversion model resistivity depth sections from a Spectral IP/Resistivity survey.

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Depth resolution and penetration is enhanced compared to Resistivity inversion models as depicted in this sample image.  In this case, resistive sections have valid data to ~2km deep.  The transmitter electrodes are typically on the order of 2.5-3 km apart connected with shielded 10-gauge copper wire and located between 10 km and 30 km from the work area.  In the attached sample, the transmitter was 20.5 km away.

Near field effects can start at 1000 Hz but can be extended to a couple hundred Hz if the transmitter is far enough.  Electrodes are grounded using several 4-foot 3/4" stainless steel rods combined with a few rolls of aluminum foil and salt over a permanently wet boggy 4 sq-m area.  This insures transmit currents of approximately 10 amps throughout the project.

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A diesel motor-generator is used to power the Phoenix TXU-30 20 kW transmitter.

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The receiver side consists of a Phoenix V8 transmitter and 1 or 2 Auxilliary receivers connected with a radio link.  The AMT magnetic coil is typically located several metres from the V8 receiver and 1 of the auxilliary receivers.  Lithium ion race-car batteries are used to power the receivers in all conditions.  With 3 electrical dipoles possible per receiver, up to 9 electrical dipoles can be read for each setup.  A survey crew of 6 or 7 workers allows for at least 10 spreads or 90 individual soundings per day.

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Results are processed with Phoenix software and inversion modeled in 1d using ZondMT1d.

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The individual 1d soundings are then merged into 2d depth sections and 3d voxels which can be sliced for different depth cuts - typically to 500 metres deep and deeper if valid, as per the above sample depth section.

The CSAMT method is also considered for geotechnical investigations such as imaging areas of karst terrain where voids are a concern for infrastructure.

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