Brownfields exploration is being undertaken in the Mount Allen Syncline area north of Kapunda, seeking extensions to apparently stratabound copper mineralisation which occurs in the historic Kapunda mine locality. Initially, 1:25,000 scale geological field mapping was undertaken by Utah to outline the areal distribution of the target host rock unit, the Neoproterozoic Eudunda Arkose Member of the Tapley Hill Formation, and to record possible ore-controlling facies variations within this unit. Rock chip (15) and stream sediment (96) geochemical sampling were next performed in the vicinity of Eudunda Arkose outcrop/subcrop, to try to characterise the geochemistry of some observed facies variations. Because the resulting assay values proved confusing owing to large supergene dispersion effects, a programme of 18 traverses of rotary drag-bit drilling into bedrock was carried out in February 1974 (78 holes, total 1935 m) to obtain relatively unweathered samples of the target metasediments, including hanging wall and footwall Tapley Hill Formation rocks, for repeat analysis. This work on 1266 subsurface samples yielded a maximum 125 ppm Cu anomaly from the soil 'C'-horizon on line 15, amongst other low order but strike-persistent copper values that follow the fold trace of the buried Eudunda Arkose Member. It was decided to drill a 350 m deep diamond corehole on the line 15 copper anomaly to obtain bedrock information about the source of the anomaly, but this hole was not begun before expiry and renewal of the licence.