Exploration undertaken by Western Mining Corp. across a number of adjoining licences located to the north and north-east of Woomera, in a search for possible economic Mount Gunson - type stratiform copper mineralisation that could have formed within a sequence of buried Adelaidean metasediments of the eastern Stuart Shelf occupying the southern Arcoona Plateau region, initially comprised ground geophysical surveys aimed at delineating several interpreted regional magnetic and gravity anomalies, followed by targeted deep stratigraphic/exploratory drilling at confirmed prospects. The subject licence area lies just to the west of the north-northwest trending Torrens Hinge Zone (THZ), a major basement-penetrating structural feature which borders the Stuart Shelf and is located approximately under the western margin of Lake Torrens. Existing deep drillhole stratigraphic information for the region was restricted to that derived from the Clarence River Basin Oil Co.'s Woomera 1 located at Phillips Pond, on the Arcoona Plateau west of the THZ, which bottomed at 611.28 m within the Late Middle Proterozoic Pandurra Formation. One favoured exploration model being addressed by WMC on the basis of the Woomera 1 stratigraphy was the possibility of copper mineralisation occurring at the Pandurra Formation - Whyalla Sandstone unconformity. At the outset, WMC's interpretation of available 1:250,000 scale regional geophysical data, looking for associated gravity and magnetic anomalies like those observed at Mount Gunson, identified a series of six magnetic anomalies of up to 3200 gammas intensity which appeared to ring a ~20 mGal gravity anomaly centred near Arcoona Homestead. To allow estimation of the depth to basement at these magnetic features, ground magnetic and gravity survey traverses were run. Geophysical modelling of the results allowed the selection of two targets for priority drilling. While the ground geophysical surveys were in progress during mid-1976, WMC also undertook surface geochemical sampling of ironstone lag occurring in fault zones, in the hope of detecting copper which could have been scavenged from underlying horizons. All of the lag assays returned low copper values, but the ironstones outcropping at Woomera Village contained several percent of barium, an element though to be a possible pathfinder for copper. Late in 1976, two stratigraphic/exploratory drillholes were percussion precollared into the Arcoona Quartzite. Then vertical diamond hole AD1 was drilled ahead from 136.52 m to a total depth of 510.05 m during the period December 1976-January 1977. An expected sequence of horizontally bedded metasediments of the Adelaidean Stuart Shelf section was intersected down to 485.02 m depth, and below this a fractured massive haematitic rock (? Pandurra Formation or older bedrock) was encountered. No anomalous copper values were recorded from assaying of diamond drill core samples. WMC noted a similarity in rock type between the fractured haematitic rock found at the bottom of AD1, and the rock penetrated in hole number RD7 that had recently been completed at the Olympic Dam prospect. Accordingly, it was decided to follow up this encouraging feature with further drilling in the Canegrass Swamp area. Stratigraphic diamond hole AD2 was spudded in February 1977 and was drilled vertically out of its 93.04 m deep precollar to a depth of 258 m, whereat the drilling rods became stuck. The drillhole was wedged off several times in attempts to bypass the bad ground, which caused the rods to become badly jammed again at 400 m depth. Eventually the hole was able to be progressed, and it was completed at a TD of 829 m in mid-July 1977. AD2 penetrated the basement at a depth of 812.52 m. The rocks are oxidised and strongly leached ferruginous sediments, showing bedding at about 45 degrees to the core axis. Very minor chalcopyrite occurs along partings. Several fine-grained basic igneous dykes were cored in the lowermost part of the Pandurra Formation and in this basement unit. The maximum copper value returned from the basement assays was 0.1% Cu over 2.0 m. The basement core also averaged 20 ppm U3O8, with a highest assay value of 31 ppm over 2.0 m. Because of the elevated uranium content displayed by the bedded basement sampled in hole AD2, WMC shortly afterwards also performed uranium assays on the fractured drill core from hole AD1. These haematitic rocks are also anomalous in uranium, averaging 51 ppm U3O8 over a 24.85 m thick interval, with the lowermost 4.05 m averaging 117 ppm. Another ground gravity and magnetic survey was conducted during June 1977 in the vicinity of Oak Dam, to further define the magnetic anomaly on which drillhole AD1 had been sited. Other ground geophysical traverses were later conducted over the Pearson Hill and Cocky Swamp magnetic features, and ongoing work was planned for the Horse Well and Winjabbie Dam features.