Case Studies

Pend Oreille

Multi-metal lead/zinc (MVT type deposit)

Blind test successfully imaging a
MVT deposit at ~ 500 m depth

This blind test of muon geotomography demonstrated the effectiveness of the technique to image a Mississippi Valley Type (MVT) deposit. It also showed that a compact ore shell model could only be produced with a combination of muon tomography and 5% of the drill data.

Teck’s MX700 deposit is an MVT lead/zinc ore body deep underground in Washington state, USA. It had been well-drilled and its wealth of geological data would provide a good blind test for muon geotomography. Afterwards it could be used to study how few drill holes would be required to produce a good ore shell model.

Placing four muon detectors at depths of 650 m provided good views for 3D imaging. First a blind test was performed; then the geological model was refined using a combination of muon geotomography and 5% of the available drill data.

Successful blind test with muon geotomography, followed by a refined ore shell model combining muon tomography and 5% of the drill data.

Overview of project site showing the ore shell,  slices of the 3D inversion and detector locations.

Closeup of ore shell model. Detectors are shown as cubes.

Presented at:

Presented at:

Myra Falls Mine
BC, Canada

(VMS type deposit)

Imaged a VMS deposit at ~300 m depth in mountainous terrain

Muon geotomography imaged the Price deposit, a multi-metal VMS ore body at Nyrstar’s Myra Falls underground mine in BC, Canada. The survey was conducted on the side of a mountain.

The ore body is located under a provincial park in an environmentally sensitive area. Exploration drilling from the surface was to be avoided. This polymetallic volcanogenic massive sulfide (VMS) deposit contains zinc, copper, lead and silver, providing good density contrast from the surrounding rock.

Using muon detector locations at a depth of about 300 m in mountainous terrain the Price deposit was mapped in 3D.

The muon geotomography results agreed well with measurements from underground drill core data.

“Because this technology has the potential to detect and image deposits at depth, it will refine the exploration search area, which will reduce the amount of expensive drilling required and further efforts to minimize environmental impact”

Rick Sawyer, P. Geo,
Manager, Exploration and Geology
Nyrstar Myra Falls Ltd.

Price deposit shown with a slice of the 3D density model from muon geotomography

Closeup of ore shell model with section of density profile from muon data. Detectors are shown as cubes.

Presented at:

McArthur River
Uranium Mine

Uranium (high grade

Imaged a compact high-grade uranium deposit at ~600 m depth

Muon geotomography successfully imaged a compact high-grade uranium deposit under 600 m of sandstone at the McArthur River uranium mine. These deposits are virtually impossible to detect with conventional geophysical exploration techniques.

Canada’s Athabasca Basin hosts the highest-grade uranium deposits yet found. This ore body at the McArthur River mine in Saskatchewan, Canada, is near an unconformity, above the basement rock, but under almost 600 m of sandstone. In addition to the depth, other challenges include complex geology and naturally occurring radiation.

Muon detectors were placed at a depth of 600 m providing a large field of view (over 1 km across on the surface) with sufficient locations to enable good 3D imaging of the deposit despite complex geology.

Muon geotomography successfully imaged this high-grade uranium deposit with high statistical significance, demonstrating a new technique for discovering hard these hard-to-detect deep compact high-grade deposits.

Overview of project showing the compact ore shell at about 600 m depth, the detector locations (cubes) and a section of the density profile from muon data.

Closeup of ore shell model with section of density profile from muon data. Detectors are shown as cubes.

Radiometric image from one muon detector showing the high-grade deposit (dark region).

Presented at:

Presented at:

Multiple Projects
& Locations

Several (zinc, copper, lead,
silver, uranium)

Our results have also been presented at numerous conferences

BHP Nickel West
Cliffs Mine
WA, Australia

Underground narrow-veined nickel deposit (Volcanic-Komatiite-type deposit)

Blind trial successfully imaging a 3-7m thick deposit at 200m depth

This blind* test of muon tomography demonstrated the effectiveness of the technique to image a high-grade nickel deposit. The results agreed with existing drill data and revealed additional characteristics of the deposit such as the weathering profile and indication of a previously unknown branch of the orebody.

*Data that validated our results was only provided after the survey and analysis were complete.

The Cliffs nickel deposit is an underground narrow-veined, vertically disposed nickel sulphide deposit situated 700km NE of Perth, Australia, near the Mount Keith operation. The deposit lies within the Agnew-Wiluna greenstone belt, which also hosts other significant nickel sulphide deposits. BHP’s Nickel West operation is a fully integrated mine-to-market nickel business that mines and processes high-grade nickel sulphide ore from Cliffs and adjacent sites (Mt. Keith, Leinster, Yakabindie). There was some drill data available for the project area, but this was not provided before the muon tomography survey was performed.

Ideon developed simulations in 2019 and deployed five muon detectors to Australia in spring 2020, navigating unrest in Hong Kong, quarantine requirements in Australia, and emerging evidence of what was to become the COVID-19 pandemic. Ideon staff traveled to the site to deploy the detectors, which were situated about 30m apart in an underground drift approximately 200m deep in the Cliffs mine. Data were gathered over a period of 60 days, with collection ending in June 2020. Data intake and analysis was conducted remotely in Canada throughout this period to verify quality and calibration, and to develop radiographic images of subsurface density with continuously improving clarity.

Imaging results closely matched the known data signature for the target area, with high-resolution imaging yielding a more significant subsurface anomaly than expected, which corresponded to a thicker mineralization of the deposit and an additional lobe that had not been previously mapped.

Tomographic reconstruction yielded a 3D map of density that conformed well to the mineralization shell derived from extensive drilling through the ore body. The results proved the technology to the client and they have since redeployed the Ideon solution in an exploration context at > 800m.

“At Nickel West, we are excited because we’ve now seen what the detectors can do and we know that muon tomography has the potential to change the way we explore.”

Marcel Menicheli,
Superintendent of Geoscience
BHP Nickel West

BHP logo

The blue block model is derived from BHP-provided drill data (provided post-survey). The light orange wireframe represents the sulphide shell model. The red shape is the voxel inversion from muon data with no prior constraints. The muon data corresponds quite well to density block model and identifies an additional lobe of the deposit that had not been previously mapped.

Cliffs 3D model