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Primary magmatic chemical haloes surrounding komatiite-hosted nickel-sulfide deposits can potentially enlarge the detectable footprints of these systems, which are typically very small. This study examines the spatial variability of whole-rock chalcophile element concentrations within the host flow to massive nickel-sulfide mineralization at the Long-Victor Deposit, Kambalda Dome (Western Australia), where a series of ore shoots occupy into two sub-parallel channels, over a strike length of approximately 3000m. The basal komatiite flow unit flow at Long-Victor is dominated by normal background chalcophile element abundances, typical of those found in Munro-type komatiites with ages younger than 3.0 Ga worldwide. The dataset of 133 samples shows evidence for both enrichment and depletion in PGEs, as estimated from ratios of Pt/Ti, Pd/Ti and Rh/Ti above and below background values, which are typical for unmineralized late-Archaean komatiites worldwide. PGE-depletion of 50% or more relative to this background level can be reliably recognized in only a small proportion of samples. The scarcity of depleted samples is a consequence of the highly dynamic nature of the oreforming environment, and the consequent low probability of the ore-forming lavas being preserved and sampled within high-flux channel environments. Depletion signatures are largely restricted to samples in the flanking environment within the basal flow, and are found primarily both in A-zones and B-zones. Based on the current sample density, depletion is only recognized within the up-dip flank. The strongest depletion signatures are preserved in the uppermost portions of the spinifex zone and decrease in magnitude with increasing depth from the stratigraphic top of the spinifex horizon downwards. This is a result of progressive flushing by PGEundepleted recharging lava during komatiite emplacement. Enrichment signatures are largely restricted to cumulate lithologies, and are found within channels and flanks. The halo of anomalous PGE/Ti ratios, both depleted and enriched, extends to more than 400m from the conventional cut off of 0.4% Ni that defines the limit of disseminated ores, and is much more extensive and marked than anomalies defined by Ni concentrations, Ni/Cr ratios or Ni/Ti ratios. The PGE-enrichment halo is recognizable in rocks with no visible sulfide and with Ni values falling within the silicate background, and provides an effective method for vectoring towards ore during prospect-scale exploration.

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