Possible economic stratabound or epigenetic lead-zinc or copper deposits, formed in altered carbonate rocks lying marginal to the Wirrealpa Diapir, were the targets of new exploration centred on the area of the old Wirrealpa lead-silver mine. Widespread low-order surface mineralisation occurs here, giving rise to stream sediment geochemical anomalies which were variably intensively drilled and rock chip sampled by past explorers. The greater licence area overlies a structurally complex sequence of Adelaidean, Callanna Group evaporites (in part diapiric), Umberatana Group, Wilpena Group, Cambrian Hawker Group and Frome Group limestones and clastic sediments. The Lower Cambrian Wilkawillina Limestone is the main objective of the current exploration, since previous work had disclosed up to 5 km linear extent of lead-zinc prospective strata lying adjacent to the western and southern margins of the diapir. The EL 1515 joint venturers' work programme has comprised field reconnaissance and sketch mapping of all areas of known mineralisation on the licence, a critical assessment of the results of previous exploration, an appraisal of the applicability of the Mississippi Valley-type (MVT) mineralisation model to the Wirrealpa area, and the follow-up of interesting stream sediment geochemical anomalies with confirmatory soil and rock chip sampling (160 samples). A number of base metal anomalous sites warranting further investigation were highlighted. As demonstrated at the Eric prospect, which is located nearby to the east on the joint venture's adjoining Mount Chambers EL 1514, the latest field studies at Wirrealpa have indicated that typical MVT mineralisation is hosted within permeable Lower Cambrian palaeokarst features, which on EL 1515 are an integral aspect of the stratigraphy seen near the Wirrealpa Diapir. It is recommended that the future exploration focus should be directed at identifying intra-Wilkawillina palaeocaverns that may have retained significant void space subsequent to deposition of the overlying Parara Limestone, since this setting is where later massive sulphide precipitation is most likely to have taken place. Under this scenario, further attack on the fabric of the host limestone, by acids derived from the subsequent supergene oxidation of such mineralisation, should then create sag apertures in the formation beneath younger cover which may now present diagnostic evidence at surface as weakly expressed depressions and/or areas of low relief.