Four wells, drilled within 36 km of the Hughes and Denman Railway Sidings, explored for a possible Palaeozoic section and/or Upper Proterozoic or older basement, that was expected from Outback's regional gravity survey data to occur at or around 250-350 metres depth. Hard drilling conditions encountered within ?Cambrian cherty limestones in Hughes (NW) 2 and Hughes (NE) 3, necessitated their abandonment at about 240 metres depth. The other 2 wells penetrated to 418 and 549 metres respectively, and were selectively cored over short intervals in the target formations. All 4 wells terminated in the ?Cambrian sequence of redbeds, dolomites and evaporites, underlying a Tertiary to Cretaceous and possibly also thin ?Permian sedimentary cover of 247 metres maximum thickness. Traces of black soft bitumenous material were detected in Hughes (NW) 2 from 195 to 198 and from 210 to 213 metres, and also in Denman 1 from 399 to 527 metres. Occasional oil-stained quartz grains were noted in a sand from 378 to 396 metres in this latter well. All 4 wells were logged by SADME prior to being plugged and abandoned.