A crucial induced polarisation (IP) survey programme at mineral exploration and development company Koryx Copper’s Luanshya West project, in Zambia, has proven critical in the company’s commitment to advancing its exploration efforts.

The ground electrical geophysical survey, which was announced in November 2023, was strategically designed to aid in the generation of drill targets, “setting the stage for future exploration endeavours”, says president and CEO Pierre Léveillé.

The IP survey’s first phase involved a 40.1 line-km of gradient array IP at 100 m spacing, covering six targets spanning about 300 ha. These targets were identified based on consistent geochemistry anomalies, particularly showcasing a “robust” association with copper and cobalt, according to Koryx Copper.

The IP survey’s primary goal was to confirm anomalies deeper than surface sampling, thereby defining the depth of potential drilling targets.

Assessing the chargeability of anomalies was a critical aspect, providing a stronger confirmation and aiding in target depth definition.

However, Léveillé says a notable challenge was determining the depth at which drilling will be required, considering the typical cover in the Zambian Copper Belt.

“Avoiding the risk of missing the target owing to this cover, is a key consideration in the ongoing exploration efforts,” he notes.

In the first phase, the gradient array IP aimed to not only confirm, but also expand upon, the geochemical anomalies identified through soil sampling. These anomalies, characterised by a strong copper and cobalt association, have been thoroughly delineated by geophysical consultancy Earthmap Consulting’s interpretation report.

The survey strategically covered the prioritised zones, providing valuable subsurface geophysical signatures essential for defining drilling targets, with plans for an anticipated 2024 campaign.

Building on the insights gained in Phase 1, the second phase of the IP survey implemented pole dipole over IP anomalies generated in the initial phase.

The parameters for Phase 2 were intricately dependent on the geometry of the anomalies, focusing on depth and characteristics.

“This phase was instrumental in establishing the depth of the potential targets, a crucial aspect in planning the upcoming drill campaign,” Léveillé comments.

The insights gained from a previous soil sampling programme and Earthmap Consulting’s interpretation report have played a crucial role in defining these priority zones, he tells Mining Weekly.

Léveillé adds that Earthmap Consulting’s contribution to the project was significant in completing the geophysical interpretation of airborne magnetic data for the Luanshya West project.

“The resulting report identified two distinct styles of mineralisation targets, providing valuable guidance for the ongoing exploration,” Léveillé says, underlining the significance of the work programme, and stating, “this work programme was a critical step toward delineating and prioritising drill targets”.

The comprehensive review and interpretation of existing geochemical, geological and regional airborne data have resulted in the identification of six prioritised zones, indicating a promising foundation for detailed follow-up groundwork, he confirms.