Buried basement-hosted iron oxide - associated copper-gold (IOCG) mineralisation of either Moonta-Wallaroo or Olympic Dam style is the target of exploration across a number of scattered Exploration Licences trending from Port Broughton in the south to Port Augusta - Stirling North area in the north. Licensee Avoca Resources' (Avoca) original exploration strategy for the project was to identify geophysical anomalism which might represent such mineralisation, i.e. gravity anomalies occurring adjacent to interpreted Hiltaba Suite intrusive granite bodies, with or without a coincident magnetic anomaly. Subsurface structures originating from or cross cutting the adjacent granite were also regarded as important ingredients for the formation these deposits. Limited historical drilling of basement in the region had encountered haematite-altered and brecciated Wandearah Metasiltstone country rock, but in the main had unsuccessfully targeted magnetic anomalies, the sources for which are now interpreted to lie at great depths. Avoca's initial targeting was carried out using available regional aeromagnetic and gravity data, combined with the historical drill hole information. The data interpretation identified two possible IOCG target areas, Wandearah on ELs 2749/2922 and Wokurna on EL 2920, where infill gravity acquisition was thought to be warranted. The Wandearah detailed gravity survey, carried out in two stages during September 2002 and December 2002-January 2003, involved reading 1476 new ground stations, mostly on freehold land, at a nominal station spacing of 400 m x 400 m. The resulting data defined a large 3 mGal anomaly with an almost 17 km strike length, that appeared to be bounded on the north and south by north-west trending structures. Modelling of this data, combined with the regional magnetic data, was contracted to Jim Hanneson of Adelaide Mining Geophysics. His work highlighted several discrete smaller positive residual gravity anomalies that could be related either to basement highs and/or haematite-rich bodies. The Wokurna detailed gravity survey, acquired during September 2002 and February 2003, involved 191 stations read along mostly east-west running roadsides, at a station spacing of 500 m. The results of this survey were dominated by a strong gradient increasing towards the south, that was conformable with existing regional data. In the centre of the survey area, a weak linear north-south trending anomaly was discernible. To better assess the likely IOCG prospectivity of the above-mentioned Wandearah coincident magnetic and gravity anomaly, which Avoca interpreted to be caused by haematite-altered Palaeoproterozoic rock lying beneath younger cover sediments, the company commenced surface geochemical exploration above it during April 2002. After performing an initial orientation survey of 18 samples collected near the North Broken Hill PP5 drillhole location, plus another 15 samples taken near Redhill, 180 regional soil samples were collected at between 2 km and 4 km spacings along roadsides during July-October 2002, covering Wokurna and Katinka as well as the Wandearah and Redhill target areas. These samples were subjected to multi-element assaying via both water leach with an IC-PMS finish, and complementary enzyme leach methods, in order to mimic published techniques previously used in exploration at Olympic Dam. The results of the water leach surface geochemical sampling identified an area south of the Broughton River where coincident Cu-U-REE anomalism overlies a residual gravity high modelled to be 250 m deep. Correlation of assay values was observed between Cu and As, Te, REE and U, and between Au and Hg. Some less obvious Cu-U-REE anomalism was also seen at Redhill, but in a different surface geological setting, being situated on the eastern edge of the ABC Range Quartzite outcrop. Late in 2003, the Wandearah detailed gravity data collected previously by Avoca on EL 2749 was remodelled by consultant Chris Moore using his 3-D inversion software. This resulted in definition of a small, discrete two-peak residual gravity high anomaly that is separate from the main anomaly cluster, a little distance to the north-east. The separate gravity feature was seen to coincide with surface trace element geochemical anomalies identified by the 2 km spaced roadside sampling carried out during 2002. This new target was referred to by Avoca as 'Southbank', due to its location just south of the Broughton River. The depth to the source of the gravity anomaly was interpreted by Chris to be approximately 300-400 m. To confirm the anomalous surface geochemistry, infill enzyme leach soil sampling was conducted on a 200 m x 200 m grid over the westernmost of the two residual gravity highs at Southbank during January 2004 (total 162 samples, comprising 125 samples collected on EL 2749 and 37 samples collected on EL 2922). Interestingly, the highest copper value recorded, 543 ppb Cu, was >50 times the background concentration. The circular copper anomaly also had coincident elevated gold (up to 1.25 ppb Au), U and REEs surrounding the gravity anomaly. Avoca interpreted this relationship as very typical for enzyme leach geochemical data, where above a mineralised body so-called 'apical' and 'oxidation halo' anomalies develop, depending on how reduced the source is and what the depth to source is. Following this compelling closer delineation of the target zone at Southbank, and after making fruitless attempts to attract a joint venture partner to co-fund the drilling of it, Avoca acting alone drilled a single vertical exploratory NQ2 diamond cored hole, WDD001, to TD 466 m (126 m percussion precollared) at the centre of the gravity anomaly during July 2004. This drillhole did not reach the target Palaeoproterozoic basement, but was terminated while still within the Tapley Hill Formation after passing through predominantly thinly laminated carbonaceous black shale containing numerous intervals of blebby pyrite. 212 cuttings and core samples taken from 2 m depth intervals were assayed, but the results were generally subdued. A few elevated copper values to 189 ppm Cu, plus anomalous lead and zinc levels, were recorded from shales and carbonaceous mudstones cored at the bottom of the hole, which contained visible minor blebby chalcopyrite and arsenopyrite (plus ?sphalerite). Avoca deemed it questionable whether the enzyme leach soil anomaly could have been caused by the amount of sulphides observed in the hole, but regardless, the target gravity anomaly remained unexplained. Thus it is possible that haematite +/- Cu-Au mineralisation may exist at depth beneath WDD01, but it would probably not be economically viable at such a depth. Consequently, no further work was planned or recommended for the Southbank target. On 14/6/2005, Avoca was able to secure a major joint venture partner, Teck Cominco Australia Pty Ltd (Teck), who had agreed to exercise an option to spend $1.5 million over 4 years to earn an 80% interest in the Moonta North tenement group, including a required expenditure of $250,000 in the first year of the option. Both Avoca and Teck subsequently combined their expertise to re-evaluate all of the accumulated exploration data from within the project area, to try to define significant targets for diamond drill testing. The JV's immediate preference was to further drill for kimberlite diatremes in the area situated approximately halfway between Redhill and Koolunga, which is located on the western edge of a regional diamond indicator mineral anomaly identified by various workers. The area also lies on the 'G2' gravity lineament, a deep seated crustal scale fracture that has been active since the Proterozoic and may have provided a conduit for emplacement of kimberlite intrusions such as the Eurelia kimberlite dyke swarm, located to the north-east. The local geology is dominated by tightly folded Adelaidean sediments which appear to be intruded by a number of small magnetic bodies. Detrital and primary intrusive diamonds have been found at the corresponding location on the other side of the same gravity corridor, at Yarcowie and Pine Creek. The Redhill prospect on EL 2749, which comprises a number of discrete magnetic anomalies at an estimated source depth of 100-150 m lying within the broad 'G2' crustal lineament zone 20 km south-east of Crystal Brook, was considered by Avoca to probably arise from kimberlite diatremes. The partial leach surface geochemical results obtained there were inconclusive, as were the determinations on 15 bulk loam samples sent for diamond indicator mineral analysis, but nevertheless Avoca decided that this target should also be tested with drilling. Fortunately, PACE Initiative Year 2 collaborative drilling project funds were able to be obtained from PIRSA to assist with the drilling of an interpreted dipolar aeromagnetic anomaly, which Avoca believed held good potential for finding a diamondiferous kimberlite intrusion in basement beneath about 100 m thickness of Cainozoic cover, particularly as the prospect lies within a regional kimberlite indicator mineral field, with previously recorded nearby occurrences of picroilmenite and kimberlitic zircon in drainage samples. During September-October 2005, a single vertical exploratory drillhole, RED001, was completed at the Redhill prospect to a total depth of 285.6 m. Rotary mud techniques were used to drill through the overburden to 167.7 m depth, after which NQ diamond coring took place. The uphole section is a sequence of Recent alluvial sands and clays mixed with lignitic layers of mangrove sediments that are related to the Broughton River floodplain system. The pre-Cainozoic basement penetrated below 167.7 m consists of folded Proterozoic siltstone metasediments extending to a depth of 187 m, that grade into a chloritic shear zone which continues to a depth of 200 m. The hole then encountered an unaltered fault breccia of siltstone to 225 m, before it passed into a highly magnetic dolerite intrusion. This intrusive body exhibits a fine grained chilled margin texture which grades into fairly coarse grained dolerite by the end of the hole. Minor late-stage quartz-carbonate-pyrite veinlets are present at regular intervals within the dolerite, but no significant mineralisation or geochemical anomalism was detected in it. The magnetic susceptibility of this dolerite is sufficient to explain the magnetic anomaly seen at the surface. No kimberlite was intersected by the drilling. After a large reduction was made to the Moonta North Project acreage by the surrender of three licences on 22/5/2006 (see Env 12057), no work took place on the remaining two licences (Port Pirie EL 2922 and renewed Crystal Brook EL 3459) during the period July 2006-June 2007. Late in this period, Teck decided to relinquish its farm-in option with Avoca. During June 2007, Rex Minerals Ltd (Rex) negotiated the purchase of certain exploration licences held in South Australia by Avoca, which included the Moonta North Project ELs 3459 and (renewed) EL 3876, and thereafter assumed management of those tenements. Rex soon undertook a geological review of the project datasets, with an emphasis on determining the licences' potential for hosting IOCG mineralisation. This work identified the need to acquire additional infill ground gravity readings over the main regional anomaly at Wandearah to better define its structural characteristics. After a several month delay with contracting the proposed survey, data acquisition for it commenced in December 2008 [Note: no details were furnished to PIRSA before the end of the subject data release reporting period].