A 106 square km area, comprising two blocks which cover the main historic copper and gold - producing districts centred around the towns of Moonta and Kadina, is being explored afresh in an attempt to identify ore resources of quantity sufficient to allow mining to be resumed. The strategy initially envisaged by Adelaide Resources as making this attempt worthwhile was based on the company acquiring a newly made possible ultra-high resolution aeromagnetic survey and complementing this with the recently developed calcrete geochemical exploration methods. Work undertaken during Year 1 of the joint venture project consisted of the flying during December 1996 of a *** line km ultra-detailed airborne magnetic and radiometric survey, using 80 m flight line spacing and 40 m sensor mean terrain clearance, plus the conduct of thorough geochemical orientation studies on local surface soil geological materials, the subsequent collection and assaying of 3667 reconnaissance and infill calcrete geochemical samples, the drilling of 154 RAB holes totalling 1360.8 m to sample Palaeoproterozoic bedrock geochemistry, and the drilling of 14 RC percussion holes for 663 m to test the prospectivity of three areas of copper-gold anomalous bedrock located near Moonta. Consultant Chris Anderson was retained by Adelaide Resources to perform an interpretation of the airborne geophysical data. Despite providing an improved regional structural map of basement, the geophysics outcome in terms of allowing direct targeting of mineralisation proved disappointing, as the magnetics were too noisy, making it difficult to recognise known lode structures, while the radiometric response was dominated by surface contamination from past mining activities. The calcrete geochemical data appeared to be more promising, except in areas where transported mine spoil contamination is rife, with nine copper-gold anomalous areas identified, some positioned over recorded underground mine workings, but others occurring in places where there had never been any previous mining. The anomalies were defined where an appreciable number of calcrete samples assayed >30 ppm Cu and/or >3 ppb Au. The bedrock sampling RAB drillholes were mostly terminated in hard, silicified Moonta Porphyry, and rarely in granite, pegmatite or hydrothermally altered Palaeoproterozoic metasediments (phyllite, schist, meta-carbonate or chert), although many holes could not penetrate beyond the overlying clay saprolite. An average cover thickness of around 11 m was recorded, consisting usually of aeolian sands with nodular calcrete horizons overlying Hindmarsh Clay, that in turn is often underlain by Tertiary fluvial sands and gravels. Bedrock copper values of >100 ppm Cu were recorded along eight RAB traverses, and along one short traverse running ~2 km east-southeast of Wheal Hughes, trace amounts of secondary copper sulphides were observed in drill cuttings. The follow-up RC drilling produced several encouraging mineralised intercepts, including 6 m @ 2% Cu + 0.28 g/t Au from Karkarilla [line of lode], and 3 m @ 2.1% Cu from Goldsworthy. The major advance in understanding gained by the joint venture partners at this point in the work was the recognition that trace metal depletion, occurring in mineralised lodes at and just beneath the cover-host rock interface, may be very strong, e.g. in such depleted zones the concentration of gold was seen to be at or near 1 ppb, while the copper content seemed to be only around 100 ppm or so, but at slightly deeper levels (usually below the depth of earlier explorers' RAB drilling blade refusal at the top of highly silicified bedrock) it appeared that near-economic concentrations of copper and gold may be present. The recognition of this factor enabled Adelaide Resources to define many new drilling targets. During Year 2 of the JV project, Adelaide Resources completed a 33 hole inclined and vertical RC percussion drilling programme during April 1998, totalling 1710 m, to test four target areas (MO3, MO5, MO6 and MO7) defined by geochemical anomalies arising out of recent and historical bedrock drill sampling. The aim now, though, was to penetrate more deeply into the basement, to reach the interpreted level of supergene copper-gold enrichment. Two of the target areas yielded encouraging sub-economic copper intercepts. At Karkarilla, a best result of 9 m @ 0.73% Cu, including 1 m @ 3.61% Cu, was returned from hole MO5-0192, from lode material containing native copper, malachite, chalcocite and chalcopyrite. Gold concentrations of up to 1152 ppb Au over 4 m were also recorded. At the historic Parrara workings, almost all of the 14 RC holes drilled encountered anomalous levels of copper, while 5 holes also had anomalous gold. Hole MO3-0173 returned 32 m @ 0.44 ppb Au and 0.15% Cu, and hole MO3-0179 had 24 m @ 0.33% Cu, including 4 m @ 1.15% Cu. No exploration occurred on the Moonta Porphyry JV ground during 1999 and 2000 (Years 3 and 4 of EL 2247) due to Adelaide Resources concentrating its efforts on other licences in its tenement holdings. On 9/3/1998, BHP Minerals Pty Ltd as farminee entered into a separate base metal exploration joint venture (the "Wallaroo" JV) agreement with EL 2247 licensee Amalg Resources, seeking to find Mount Isa style copper mineralised systems within reduced Proterozoic metasediments in the eastern and north-eastern parts of the tenement area, where past exploration activities had been less intense, and where several large basement structures exist. The historic mining fields at Moonta and Kadina, already being addressed by the exploration agreement made previously with Adelaide Resources, were excluded from this later dealing. Besides conducting a review of all available previous exploration data, BHP carried out an in-house aeromagnetic data interpretation which highlighted the structural complexity of the licence area. An analysis of the sequence of formation of regional shear zones, shallow dipping thrust faults and other types of faulting, and their possible interaction to produce probable controls on mineralisation, was attempted as a basis for planning new work. Initial major work performed by BHP was the acquisition during July-August 1998 of an airborne electromagnetic and magnetic survey using the 25 Hz GeoTEM equipment platform. A total of 2761 line km were flown along east-west lines spaced 500 m apart, with an average EM receiver height above ground surface of 62 m. Immediately prior, over five days in May, nine ground-based SIROTEM resistivity soundings were acquired for BHP by Solo Geophysics, to evaluate the suitability of the Wallaroo JV area for doing the airborne survey. Upon data inversion, the low conductivities recorded for various cover units, in the main producing a total interval conductance of less than 20 Siemens, indicated that airborne EM methods would be able to 'see' basement conductivity variations and possibly also, conductive sulphide mineralisation. Following BHP's receipt of the processed AEM data, 69 EM anomalies were selected as worthy of further investigation, and were assigned to a 3-tier priority ranking. In the north-western part of EL 2247, patchy areas of high conductivity predominate. Poor correlatabilty of these EM features between adjacent flight lines suggested that they have a non-stratal source. Because this locality is also a gravity low, this implied that the higher conductivity features could arise from deep weathering of basement, and/or the presence of palaeochannel fill. Disappointingly, BHP could discern no significant conductive strata in the GeoTEM data which could indicate large Mount Isa style stratigraphic packages of reduced metasediments. The southern part of the licence area was generally seen to be particularly resistive in the GeoTEM response. This observation was attributed to the cover sequence there being composed largely of limestones that resist weathering. Many potentially hydrothermal fluid - carrying basement structures were interpreted from the AEM data. However, a large half-graben bounding fault running along the eastern edge of the survey coverage, which was taken as marking the principal vertical expression of the Torrens Hinge Zone, has downthrown the pre-Adelaidean basement to depths that BHP said would preclude any AEM flown there from obtaining a defineable bedrock response. Late in 1998, BHP collected 663 calcrete samples from the eastern and north-eastern parts of EL 2247, to look for base metal anomalism originating from the more reduced bedrock packages mapped on the licence. The samples were taken on a 1 km grid spacing, with some infill samples collected over Pridhams lode at 500 m x 250 m spacing. 4 kg of nodular calcrete material were dug on average from 40 cm depth and sent for assay by BLEG and emission spectrographic methods. 25 coherent copper anomalies were returned, which were prioritised for future evaluation by weighting them using the reliability of related geochemical, geophysical and geological/structural parameters. During the next year, BHP undertook follow-up calcrete soil sampling (174 samples) at four preferred anomalies, Black Oak, Willamulka, MG020 and MG007 (Pridhams North), as well as continuing regional calcrete sampling around the Copper Hill prospect (110 samples). Only Black Oak produced coherent anomalism at detailed sample spacing, with >5 ppm Cu and >0.26 ppm Co values extending for ~1.5 km along the contact between reduced and oxidised rocks. In early January 1999, moving loop SIROTEM surveys were acquired over six GeoTEM conductivity anomalies, but no strong bedrock conductors were indicated, and it appeared that the z-component AEM response had been caused by near-surface clay horizons or deeper weathered intervals within Tertiary sediments. Nevertheless, BHP decided to carry out a limited programme of RC drilling to test the most contrasting EM and soil anomalies. 8 inclined RC percussion holes were completed for a total penetration of 775 m during January-February 1999. Drilling of two EM anomalies encountered highly saline groundwater in porous saprolite units, plus minor pyrite within a wide clay-filled fault zone, which adequately explained the geophysical anomalies. Only minor copper and cobalt was encountered in the faulted section of hole WR99002 (24 m @ 310 ppm Cu and 21 ppm Co). To investigate soil copper anomalies in the Black Oak area, six RC holes were drilled, which encountered metasediments and igneous intrusive units showing partial alteration to biotite, albite and haematite. Patchy low grade mineralisation, in the form of chalcopyrite occupying quartz-carbonate-haematite veins within calc-silicate altered metadolerites and sheared metasedimentary rocks, appeared to BHP to resemble Wallaroo type copper occurrences, but the degree of mineralisation was small and unattractive. Petrographic studies were performed on drill chip samples from three drillholes, the findings of which suggested that locally there had been a long progression of contact metamorphism and alteration caused by emplacement of a multiphase dolerite/granophyre intrusive suite. Because of its disappointing drilling results, which were suggestive of the likely existence of a scale of mineralisation unsuited to its corporate objectives, BHP elected on 17/9/1999 to withdraw from the Wallaroo JV agreement with Amalg Resources. Subsequently, Amalg Resources and Adelaide Resources tried for two years to attract new joint venture partners into EL 2247, and several Australian companies expressed strong interest, but negotiations with them failed to secure the funds necessary for resuming field work. On 9/8/2001, during Year 5 of EL 2247, having earned 90% of the Moonta Porphyry JV area mineral rights, Adelaide Resources agreed to exercise its pre-emptive option, made as original farminee, to purchase the entire licence from Amalg Resources before April 2003, the monetary consideration being the payment of a cash or share price of $100,000 plus interim licence management fees. When it re-commenced exploration after a 2-year hiatus, the new licensee commissioned consultant geologist Gary Maddocks to review all of the exploration data so far obtained in the greater Moonta-Wallaroo region, including that recently generated by BHP Minerals, in the context of how well these data matched the latest published models for iron oxide - associated copper-gold (IOCG) mineralisation generative systems within crustal rocks. It was deduced from making this review that the northern part of the licence area would have the most potential for finding IOCG mineralisation, due to metasomatised metasediments there being in contact with the Hiltaba age Tickera Granite for ~30 km along the so-called "Alford Magnetic Zone". However, many other places elsewhere on the tenement also exhibited IOCG prospectivity by virtue of fragmentary recorded evidence of similar style copper-gold occurrences.