The main exploration activities undertaken during the first year of tenure of renewed EL 4239 (licence Year 6, 2009-2010) consisted of drill testing of uraniferous prospects defined by previous exploration, after the prior acquisition of an...
The main exploration activities undertaken during the first year of tenure of renewed EL 4239 (licence Year 6, 2009-2010) consisted of drill testing of uraniferous prospects defined by previous exploration, after the prior acquisition of an airborne magnetic/radiometric/DEM survey and a complementary ground gravity survey over the western end of the tenement area. The aim was to progress the Draft Bankable Feasibility Study for proposed development of a new uranium mine at the Crocker Well deposits located within EL 4375, by delineating other uranium deposits within EL 4239 which could supplement those known resources. During May-June 2009, high resolution semi-detailed helicopter borne magnetic, radiometric and digital elevation model data were acquired over the western part of the tenement area as part of a larger Crocker Well Project airborne survey acquired mainly within SPCM's adjoining EL4375 Bimbowrie. On EL 4239, ~10-15% of the total 5758 line km survey coverage was flown along north-south lines spaced 50 m apart, using a 50 m mean terrain clearance. Preliminary interpretation of the magnetic data showed very strong regional NW and WNW structural trends and, to a lesser degree, NE orientated structural trends. A number of significant high amplitude magnetic anomalies occur, which were interpreted as being associated with quartz-magnetite units (Bimba Formation) in the vicinity of Billeroo. These units have historically been explored for copper mineralisation. A number of the newly defined magnetic anomalies have magnitudes in excess of 10,000 nT, close to the amplitude of the magnetic anomaly associated with the Ernest Henry IOCG deposit. The new radiometric data defined a number of U-channel anomalies at the Becaroo, Anomaly 'A' and Billeroo prospects. At Becaroo and Anomaly 'A’ , earlier rock chip sampling had returned high grade U+REE values to maxima of 26.2 kg/t U3O8 + 4.42% REE, and 24.1 kg/t U3O8 + 5% REE respectively. During July 2009, an infill ground gravity survey was acquired in order to improve coverage over the Crocker Well uranium deposit area and the nearby region, where the historical gravity station density was approximately 7 km. New semi-detailed gravity data was read on a 1 km x 2 km grid, mainly within EL 4375, but 40 of the 356 stations total was read within EL 4239. This new data defined a series of gravity highs, albeit outlined by only a limited number of data points, which are associated with moderately to strongly magnetic quartz-magnetite units. SPCM noted that historical drilling had primarily targeted magnetic units, with defined gravity anomalies not specifically targeted and thus remaining either partially tested or untested. During October 2009, a water bore drilling program was undertaken for SPCM by consultancy URS, as part of the Crocker Well Feasibility Study, to investigate possible water sources for planned development of the Crocker Well uranium deposits within EL4375. A total of 11 holes for 467 m were completed along three transects. Some evidence of saturated sediments was seen in three holes on the southernmost drill traverse, at about 30-40 m depth, which would imply that porous palaeochannel channel sands may exist towards the west in this vicinity. During November-December 2009, the joint venturers carried out a campaign of inclined RC percussion exploratory drilling to test the U channel airborne radiometric anomalies recognised at Becaroo and Anomaly 'A'. 11 holes for a total penetration of 1086 m were completed at Becaroo, returning encouragingly anomalous U and anomalous to highly anomalous REE (Ce + La + Y) assay values from downhole sampling of medium grained alaskite, tonalite and migmatitic rocks, e.g. 80 m @ 116 ppm U, 306 ppm Ce, 310 ppm La and 94 ppm Y in hole RC09BEC010. Narrow higher grade intervals were observed to occur within broader zones of elevated or anomalous values. 7 drillholes for 650 m were completed at Anomaly 'A’, where testing of the main radiometric response disclosed a limited number of narrow uranium and REE mineralised intervals, to a maximum of 2 m @ 320 ppm U + 0.12% REE. It was concluded that further work is needed at the Becaroo prospect to determine if broader zones of weak to moderate grade uranium and REE mineralisation exist beyond the limited places that were tested by the recent drilling. During the seventh licence year, in May 2010, part of a detailed airborne magnetic/radiometric/DTM survey was flown over most of the tenement. It defined a number of priority magnetic and radiometric anomalies that warranted follow-up. A later program of soil geochemical sampling, done by SPCM in conjunction with a review of historical geological and rock chip geochemical maps, highlighted the potential of these geophysically anomalous areas to host buried Cu-U-Zn mineralisation. On the three Kalabity Project ELs, 6374 line km were surveyed by fixed-wing aircraft along north-south flight lines 100 m apart, using a mean sensor height above the ground surface of 50 m. Interpretation of the survey data acquired over EL 4239 by consultant David Isles produced 12 high ranking target areas. 76 vertical or inclined aircore holes for 1876 m were drilled by SPCM in December 2010 to test three of these areas (Areas 1, 2 and 3). The drilling results downgraded the potential of two of the areas to host economic unconformity - related uranium mineralisation. However, drill testing of an intense magnetic feature (Area 3) intersected rocks carrying anomalous Cu+REE, having perceived analogies to Ernest Henry style mineralisation. The Area 3 drilling also intersected significant near-surface iron mineralisation. 1009 x minus 80 mesh size soil geochemical samples were collected during mid-2010 along ground traverses made across selected airborne radiometric U-Th channel anomalies and in other, non-uranium anomalous areas identified from SPCM's review of historical exploration data, and 425 readings of surface radioactivity were taken along these traverses using a hand-held scintillometer. The multi-element assaying of 443 soil samples from above possible uranium targets returned weakly to moderately anomalous uranium values that in general are associated with similar low tenor Cu+/-Au-Ag values. The 537 soil samples that were assayed to look for signs of possible non-uranium bedrock mineralisation produced some coincident weak to moderately anomalous Cu-Pb-Zn+/-Au-As anomalies, which were interpreted as being mostly stratigraphically controlled. Radiometrically anomalous Area 6, located in the south-western part of the licence, appeared to be the most promising, since it showed moderately to highly anomalous base metal values along broad sections of all the traverses sampled across it. Confirmatory soil sampling, that also extended the coverage of historical soil sampling undertaken by CRAE, was completed by SPCM over an intense aeromagnetic anomaly in the vicinity of Area 8. Comparison of both geochemical datasets, based on log normalisation of all assay data, confirmed that there is narrow strong Cu+Au-As anomalism associated with the intense magnetic anomaly. With regard to the ground truthing of the airborne radioactivity survey results, only Area 4 yielded something of interest, returning highly anomalous scintillometer total count readings over an eastern unit defined by airborne radiometric data, compared to soil geochemical results that returned moderate to strongly anomalous uranium values coincident with a western unit. SPCM's subsequent review of historical mapping revealed that the eastern anomaly coincides with an occurrence of altered meta-quartzite, while the geochemical anomaly coincides with mapped chiastolitic andalusite schists. The 2010 exploratory aircore drilling done into covered bedrock at Area 1 encountered narrow moderately anomalous primary uranium values associated with highly graphitic schist units. Drill cuttings assaying returned a maximum of 2 m @ 90 ppm U in drillhole AC10KAL073, from 2 m depth. Aircore drilling at Area 2 encountered anomalous saprock/bedrock uranium primarily associated with clay units and weakly weathered psammitic metasediments. Assaying returned a maximum value of 80 ppm U and an intercept of 8 m @ 60 ppm U from 16 m depth in hole AC10KAL016. The three drill traverses completed across Area 3 found abundant to common magnetite occurrences within metasediments to gneissic units, plus other iron-rich, possibly lateritic units in drillholes AC10KAL028 and AC10KAL029. Drillhole AC10KAL028 returned 11 m @ 44% Fe associated with anomalous to highly anomalous Cu-Ce-La+Y, this enriched element grouping suggesting possible geochemical analogies to IOCG styles of mineralisation. During the eighth, 2011-2012 licence year, the joint venturers undertook further drilling to evaluate both uranium and base metal/precious metal targets. A technical review was also made of historic exploration data for the area surrounding the abandoned Dome Rock copper mine. 243 shallow inclined or vertical aircore holes for 5606 m were drilled during June and July 2011, usually 100 m apart along a number of short traverses, to test the buried bedrock at six different style prospects defined either from interpretations of airborne geophysical data or from previous explorers' drilling and other work. The targets were either Bimba Formation strata dislocated by folding and faulting, or other rocks giving rise to surface soil or to past drillhole geochemical anomalies. All of the returned drill cuttings were logged in the field for their radioactivity and magnetic susceptibility using hand-held instruments, and 2912 of the cuttings samples were sent for assaying. Most of this SPCM traverse drilling either confirmed, but did not much amplify, the minor tenor of stratabound base metal mineralisation that had been indicated from previous work, or else it failed to locate any significant mineralisation associated with radiometric or magnetic anomalies. At three of the prospect areas where the aircore drilling had revealed some potential for more mineralisation to occur, SPCM conducted additional deeper drilling, of 6 inclined RC holes for 912 m, during February 2012. At the T3 prospect, a single hole RC12T3A001 was drilled to 145 m to explore beneath an iron-rich unit intersected by aircore hole AC10KAL028 (11 m @ 44.19% Fe). 145 x 1-metre cuttings samples taken from within highly weathered basement lithologies were submitted for multi-element analysis, and returned 31 m @ 36.4% Fe from 5 m. Both holes' intercepts are only weakly magnetic, suggesting that the iron most likely occurs as goethite. At the Dayanna prospect, 2 RC holes for 248 m investigated the often anomalous bedrock zinc encountered in the aircore drilling done there, looking for any development of high grade zones. 256 cuttings samples were submitted for multi-element analysis. Hole RC12DAY001 intersected 9 m @ 0.64% Zn from 81 m, whilst hole RC12DAY002 intersected 13 m @ 0.31% Zn from 3 m plus 12 m @ 0.19% Zn from 24 m, these separate intercepts both lying within broader zones of >500 ppm Zn. At the T8 prospect, 3 RC holes for 519 m (RC12T8A001 – 003) investigated some copper anomalous ground disclosed by the earlier aircore drilling (e.g. AC11KAL203: 24 m @ 0.158% Cu). 535 cuttings samples were submitted for multi-element analysis. RC12T8A002 showed a similar tenor of mineralisation, while hole RC12T8A003 revealed generally higher grade but thin copper intercepts between 83 and 150 m, including 4 m @ 1.36% Cu. During licence Year 9 (to 11/3/ 2013), the Curnamona Project exploration joint venturers continued their attempts to define base and precious metal, iron ore and uranium mineralisation in the Olary Domain. Following the conduct of an extensive data review in the previous reporting periods, a drilling program at Dome Rock North prospect was conducted in July 2012, when 13 inclined RC holes (RC12DRN001 - 013) were drilled for 1954 m, with 2075 one-metre drill cuttings samples submitted for multi-element analysis. Multiple low grade Cu intersections were recorded, e.g., in hole RC12DRN002, with 5 m @ 0.82% Cu, and in hole RC12DRN004, 5 m @ 0.68% Cu. Assessment of the prospect remained ongoing, to determine if further work was warranted. Existing aeromagnetic data covering the “Direct Shipping Ore” DSO target areas at Billeroo, Ironstone and Dome Rock were reprocessed and re-imaged into more localised datasets to try to define possible drill targets more accurately. At the Billeroo iron prospect, 14 inclined RC holes (RC13BIL001 - 014) for 2060 m were drilled, with 689 one-metre drill cuttings samples submitted for laboratory iron ore analysis, in an ongoing iron related bedrock geochemical evaluation program [No further information submitted with this report – will report in following reporting period]. The drilling encountered significant visible magnetite mineralisation, but the downhole sampling assay results were not yet to hand. A total of 21 rock chip samples were collected from several known outcropping ironstones within the tenement as part of making an evaluation of the potential for DSO iron ore in the region. Results of this sampling indicated that the outcropping iron mineralised rocks were of sufficient grade to warrant the JV partners planning a work area heritage clearance survey and an exploratory drilling program. During licence Year 10, SPCM oversaw the completion in February-March 2013 of the RC drilling campaign at Billeroo carried over from the previous reporting period, when 3 inclined RC holes were drilled for 378 m (RC13BIL015 - 017), with a total of 338 drill cuttings samples submitted for laboratory iron ore analysis. The drilling campaign overall encountered significant magnetite mineralisation, and multiple iron mineralised intersections were recorded of various grades, e.g. in hole RC13BIL003, 36 m @ 44.57% Fe, and in hole RC13BIL007, 14 m @ 51.62%. Limited DTR test work done on samples from the above drillholes indicated that an “excellent magnetite product could be obtained at a relatively coarse grind”. Subsequent processing of an 80 kg bulk sample utilising both high and low intensity magnetic separation demonstrated that the Billeroo ironstone would produce a high-quality magnetite concentrate of excellent grade. Detailed petrography was undertaken on a suite of drill cuttings samples from the zones tested by DTR, to assist with determining the physical nature of the magnetite present and the mineralogy of the gangue. A total of 20 rock chip geochemical samples were collected from several geophysical anomalies to submit for laboratory multi-element assaying. SPCM thought that the assay results obtained were promising but would require further on ground investigations before deciding if heritage clearances and drilling are warranted. During licence Year 11, work on renewed EL 5462 was undertaken and reported by Sinosteel Uranium SA Pty Ltd (SUSA), after SUSA bought out PepinNini’s 40% share of the Curnamona Project Joint Venture on 22/9/2014 and began managing all exploration within the Project tenements. New exploration conducted on EL 5462 comprised drilling of the Billeroo Iron and Ironstone prospects, together with drill sample assaying, the conduct of downhole gyroscopic surveys, and reconnaissance rock chip geochemical sampling. At Billeroo in July-August 2014, 9 inclined RC holes were drilled for 1154 m (RC14BIL018 - 026), with 794 one-metre samples submitted for iron ore XRF analysis. Multiple iron mineralised intersections were recorded of various grades including, in hole RC14BIL022, 76 m @ 44.25% Fe, and in hole RC14BIL023, 41 m @ 39.86% Fe. Petrography was undertaken on 5 drill cuttings samples from the above intersections, and the rock descriptions concurred with previous ones for Billeroo samples, indicating that the magnetite is generally comparatively coarse grained with few inclusions. At Ironstone prospect, in August-September 2014, 17 inclined RC holes were drilled for 2050 m (RC14IRS001 - 017), and 1321 one-meter samples were submitted for laboratory analyses including iron ore XRF, full spectrum ICP multi-element, and additional specific testing for gold. Native copper was logged as occurring in hole RC14IRS006, which prompted SUSA to perform the multi-element ICP analysis. Multiple Cu intersections were returned; significant intervals included, in hole RC14IRS006, 17 m @ 0.843% Cu. But, as iron ore was SUSA’s primary target within this prospect, they found the drill sample assay results disappointing in this regard. Detailed petrography undertaken on representative drill cuttings from a range of rock types indicated the presence of a significant weathering profile. It was reported that much of the magnetite in the ironstone was totally martitised or partially altered to haematite, with samples often visibly oxidised, and some containing microscopic grains of native copper and chalcocite which to the naked eye was unobservable in the weathered drill cuttings. It was suggested that the abundance of zeolite seen in the thin sections means that there was a lot of past hydrothermal fluid flow, which in turn may indicate a large fault system and/or a major structure in the area. Six rock chip geochemical samples were collected from the Calico prospect located 8 km NNW of Kalabity Homestead, with the assay results showing high iron and anomalous copper values considered promising, thus warranting further investigations. During licence Year 12, reconnaissance work to re-evaluate the iron ore potential of the whole tenement was undertaken by SUSA, based on regional geological and geophysical interpretation. Significant effort was put into the confirmation and verification of historical drillholes listed within the SARIG database, that showed encouraging information about exploration potential, as being actually located within the subject tenement area. Several generations of geophysical data acquired previously over the Dome Rock prospect were collated and reprocessing of them was begun. Previously obtained regional geophysical data were re-assessed, and new targets selected; however, it was apparent that doing more geophysical work would be required to revivify some of the targets which had been described by previous explorers. Field reconnaissance and mapping were performed at Dome Rock prospect to assess existing geophysical anomalies. A Program for Environment Protection and Rehabilitation (PEPR) was submitted to DSD by SUSA in September 2015 concerning a planned RC drilling campaign at Dome Rock prospect to test for possible buried iron ore and for copper mineralisation. This PEPR was approved by DSD in October 2015.A further 6 rock chip geochemical samples were collected, two from Calico and four from Billeroo, the assay results from which revealed potential iron ore and base metal drilling targets. During licence Years 13 and 14, no field work was done. Activity was limited to making a desktop-based data and literature review to identify exploration potential. During licence Year 15, no exploration work was undertaken. Aboriginal Heritage Clearance surveys were undertaken to allow for RC drill planning, with the final report still pending. A Program for Environment Protection and Rehabilitation (PEPR) was submitted to DEM on 15th February 2019 with regards to the plan RC drill programmes to test potential iron formation in the Billeroo Prospect, and after revision on 13th March 2019, was subsequently approved.