Dalaroo Metals (ASX:DAL) has completed an induced polarisation (IP) survey at its Watheroo Copper-Nickel-Platinum Group Elements (Cu-Ni-PGE) Project in Western Australia, defining priority targets for a deep reverse circulation (RC) drilling program.
The ground dipole-dipole IP survey, run by Fender Geophysics, covered about 6,300m across three east–west lines at the 100%-owned project, using 83 stations at nominal 100m spacing. Watheroo is located 170km north of Perth.
Chargeability values reached 19.4 millivolts per volt (mV/V), with the 2D inversion of Line 6641700N containing a modelled response of about 18mV/V. The 10mV/V interpretive contour used to define the response falls within the upper part of the contractor’s reported background range of 0–12mV/V.
“The Watheroo IP survey has materially strengthened our exploration model and, importantly, moved the project towards drill testing,” CEO John Morgan says.
Steeply dipping, high-contrast resistivity boundaries persist across all three lines and coincide with a broad Cu-Ni-sulphur-PGE geochemical halo and elevated chargeability.
The 3D inversion identifies a high-resistivity zone on the western side of the survey area, with medium-to-high chargeability concentrated along the boundary between high and lower-resistivity domains.
The boundary corresponds with a break in the airborne magnetic response, which supports the interpretation that the zone may represent a buried mafic-ultramafic intrusive body.
Exploration Manager Trystan Hughes says the strongest chargeability sits at a resistivity boundary coinciding with a major magnetic break.
“The strongest chargeability is spatially associated with a distinct, high-contrast resistivity boundary that coincides with a major magnetic break, highlighting a potentially significant lithological or structural contact within the buried mafic-ultramafic intrusive system,” Hughes explains.
From anomaly to drill target
The survey provides subsurface extension of surface geochemical results reported in August, which defined a coherent copper-nickel response about 2km south of historical sampling areas.
Peak values included 284 parts per million (ppm) Cu, 176ppm Ni, and up to 10 parts per billion each for platinum, palladium, and gold.
Watheroo sits within the western margin of the Yilgarn Craton, which hosts Chalice Mining’s (ASX:CHN) Julimar Ni-Cu-PGE deposit. Recent mapping identified extensive olivine gabbro and scattered serpentinite, with the interpreted chonolith carrying a magnetic footprint about 7km long by 3km wide.
Dalaroo is planning a deep RC program with holes about 300m deep. The program will target the strongest chargeability responses where they coincide with the magnetic and resistivity boundary, elevated Cu-Ni-PGE and sulphur geochemistry, and interpreted intrusive contacts.
The company has also planned about 360 additional soil samples.
IP responses are not diagnostic of sulphide mineralisation and may also be caused by graphite, clay-rich lithologies, weathering products, or saline groundwater.
Dalaroo Metals is an Australian explorer with a portfolio spanning the Blue Lagoon Rare Earth Project in Greenland, gold assets in Côte d’Ivoire, and the Namban and Lyons River projects in WA.
Write to JC Villarba at Mining.com.au
Main image: Dalaroo Metals
