During a search for possible Stuart Shelf - type Proterozoic or Cambrian stratiform base metal deposits within an area lying to the south of Port Pirie, exploratory percussion drilling of 5 vertical holes totalling 443 m was undertaken. Three of the drillholes failed to penetrate the thick Cainozoic cover on the Wandearah Plains, while another hole, PWD2, drilled to TD 116 m in the Barunga Ranges at the south-eastern corner of the licence area, was abandoned after reaching upper Adelaidean Tent Hill Formation. The target Pandurra Erosional Surface is thus concluded to here lie below the economic depth limit for percussion drilling. No anomalous base metal values were intersected in any hole. Hole PWD5, drilled in the northern Barunga Ranges, passed through the Skillogalee Dolomite / Nelshaby Sandstone Member disconformable contact, which may be the possible equivalent of the Pandurra Erosional Surface. This hole was abandoned in fractured quartzite at 97 m depth. A Cambrian basin filled with dense carbonate rock is presently interpreted to lie beneath the Wandearah West geophysical anomaly. It is now thought that the Cultana Batholith granitic basement rocks do not extend across Spencer Gulf onto the EL 200 area, as had been inferred previously in making regional correlations between the Cultana and Moonta basement lithologies.