Bopeechee and Cadnia Hill/Stuart Creek and Porter Hill (The Lake Torrens Project). Data release made at two licences' surrender/two latter licences' fifth partial relinquishment: annual reports and final reports for the period 9/4/1998 to 31/12/2006.
Published: 29 Sep 1909 Created: 12 Nov 2024 Revised: 05 Dec 2024

The reports comprising this data release package describe exploration for economic deposits of base and precious metals that have possibly formed within Neoproterozoic metasediments, the underlying Palaeoproterozoic basement, and in Cambrian...

The reports comprising this data release package describe exploration for economic deposits of base and precious metals that have possibly formed within Neoproterozoic metasediments, the underlying Palaeoproterozoic basement, and in Cambrian carbonate rocks present on the north-eastern Stuart Shelf and the Adelaide Geosyncline / Torrens Hinge Zone west of the Willouran Ranges. The initial work addressed perceived potential for finding Zambian Copperbelt / Mount Isa / Nifty style sedex copper mineralisation, with lesser emphasis given to locating Mississippi Valley /Irish type base metal deposits in limestones, or Beltana type zinc deposits in similar stratigraphic settings, associated with diapiric breccias intruding large structures. Exploration progressively evolved starting with a malachite occurrence in an area known as Airport Claypan, on EL 2340 to the north-east of Lake Torrens. The initial geochemical Mobile Metal Ion (MMI) survey returned encouraging results, and as a consequence the MMI sampling coverage was expanded greatly, following low amplitude magnetic features as a guide to where to conduct the sampling programmes. Many prospects also emerged via other lines of investigation, viz. from the re-analysis of anomalies identified by previous explorers, such as the unresolved gravity anomalies at Clara [St Dora] and Titan, and from the discovery of copper mineralisation at unrecorded old mine workings at Clara and West Mount. Later, most new drilling targets were generated from a coupling of ground gravity survey traverses with follow-up dipole-dipole induced polarisation surveys. For 2000-2001 (Year 1 of the amalgamated expenditure agreement reporting period for its Lake Torrens Project, having a first anniversary date of 25/5/2001) Tasman Resources reported that it employed a wide range of remote sensing, geochemical and geophysical methods. These include soil MMI and rock chip sample analyses, an interpretation of all available aeromagnetic data, a ground radiometric survey, and an induced polarisation survey. During these 12 months a total of 1,625 geochemical samples, representing 152.2 line km of traverses, were taken from various parts of the project area. The licensee commissioned a detailed report prepared by Archimedes Consulting on magnetic anomalies located within the top 2 km of a large section of the project area. In addition, Tasman Resources participated in a multi-client deep crustal aeromagnetic study conducted by Archimedes Consulting on behalf of various companies and PIRSA, which covered an extensive area of SA and NSW and included the whole of Tasman's tenement acreage. The dipole-dipole complex resistivity induced polarisation surveys carried out by the company comprised a total of five lines with an aggregate length of 13.6 line km, profiling various targets on the project.Tasman also spent much time on negotiating and concluding agreements, pursuant to Part 9B of the Native Title (SA) Act 1994, with registered Native Title claimants for the Lake Torrens region. As part of this stakeholder consultation the company conducted Aboriginal heritage surveys in conjunction with relevant Aboriginal groups, thereby obtaining clearances to enable it to carry out further exploration activity, include drilling, on twelve dispersed target areas. Following the discovery of the large Prominent Hill deposit by Minotaur Resources in November 2001, Tasman's focus shifted towards identifying drillable iron oxide - associated copper-gold (IOCG) targets in deeper basement, and also any Ernest Henry type copper-uranium-precious metal occurrences within haematite-rich granitic rocks, besides considering the potential for possible nickel-copper-platinoid metal deposits to form in layered mafic intrusions like the Bills Lookout Gabbroic Complex. Many prospects fitting into one or other of these models emerged from several sources: the re-analysis of anomalies identified by previous explorers, such as the unresolved gravity anomalies of Clara and Titan; the occurrences of old workings as at Clara and West Mount; and the anomalies generated from the Tasman geochemical MMI coverage, in particular Thrust. Exploration during 2001-2002 extended across the project licences, and included drilling of several geochemical anomalies, some with attractive IP chargeability features, such as indicated at Clara St Dora. Follow-up gravity and IP surveys conducted on several geochemical anomalies advanced certain others to drillable status, including Watermans Plain (M1) prospect in the southern sector of Marathon, the coincident gravity and chargeability highs at Clara, and the gravity high at Titan. With regard to the last-named prospect, Geoscience Australia’s examination of fluid inclusions in drill core from WMC’s 1976 drill hole BD1, in the course of their Gawler Project research, had indicated the presence of copper-bearing hydrothermal fluids in association with magnetite-rich alteration. This drillhole, although weakly mineralised, penetrated part of a hydrothermal system which Geoscience Australia (Skirrow, 2002) believed may have been too hot, at approximately 400-500 degrees C, to permit the precipitation of significant concentrations of copper minerals. By analogy with published studies of Olympic Dam, located some 32 km to the south, which indicated that the copper there was deposited under lower temperature conditions, copper would be expected to have precipitated in the cooler outer parts of the Titan prospect system at temperatures below 350 degrees C. Drawing also from newly acquired knowledge about the Prominent Hill geological setting, Tasman concluded that the peripheral zones of the Titan system required urgent assessment. Tasman's geophysical consultants (Resource Potential, 2002) had noted that the prospect’s magnetic anomaly is displaced some 400 m to 600 m west of the centre of a pronounced gravity anomaly. It was thought that this eccentric relationship could indicate haematitic alteration of the magnetite. Both anomalies overlap, are about 3.5 km long, and are aligned along what is believed to be the controlling structure. This structure, with its inferred intense haematitic alteration, constituted a copper/gold exploration target. The zone of interest occupies a vertical interval of a least 300 m from about 500 m depth, and is about 3 km in length. During 2002-2003 activities included prospect 1:5000 scale geological mapping, related soil (631 samples) and rock chip (33 samples) analyses, the resampling of stored diamond drill core from Western Mining Corp.'s 941 m deep, 1981 drilled Bopeechee East prospect exploratory hole BD1 to allow making detailed petrographic studies of the basement rocks, 43 line km of dipole-dipole and gradient array IP plus limited trial CSAMT surveying, a downhole IP survey at Clara St Dora, five detailed infill gravity surveys (2455 stations), forward modelling and inversion of gravity and IP data, and a total of 8563.3 m of RC percussion drilling, plus 376 m of diamond NQ2 core drilling, in 84 holes put down on ELs 2543, 2594 and 2772. Prospects drilled were Clara St Dora, Watermans Plain, Shelf 6, Saddle Hill and Titan. The 6 drillholes at Clara St Dora targeted coincident gravity and IP anomalies thought to reflect sediment hosted base metal mineralisation, but these were shown to arise from interbedded dolomites and pyritic, graphitic shales of the Skillogalee Dolomite. The best mineralised intercept obtained was over the depth interval 306-308 m in hole CRC002, where 300 ppm Cu was returned by laminae and discordant veinlets of magnetite-pyrite-chalcopyrite present in a weakly dolomitic meta-argillite. This mineralisation is thought by Tasman Resources to have formed during greenschist facies regional metamorphism of the original clastic sediments. The company noted that there are some stratigraphic and structural similarities between the geological setting of this mineralisation at Clara St Dora and that at the giant, high grade N'Changa mine of the Zambian Copperbelt. Gravity and IP anomalies at Shelf 6 were tested for possible MVT style mineralisation with 7 drillholes, and traces of this were met with at the top and bottom unconformities of the Andamooka Limestone and also within it in permeable oolitic facies. Similar targets at Watermans Plain and Saddle Hill were drilled in 13 holes, and iron sulphides were also encountered within the Andamooka Limestone. An attempt to deepen the single hole at Saddle Hill to investigate an IOCG gravity feature revealed by inversion modelling had to be abandoned when the hole trajectory flattened unacceptably. The 6 holes drilled at Titan were designed to test an IOCG system formerly discovered by Western Mining Corp., and to attempt to locate high grade mineralisation within interpreted chargeable, dense but non-magnetic zones believed to represent cooler, more oxidised portions of the system. The drilling encountered extensively magnetite-haematite / pyrite / chalcopyrite -altered ?Palaeoproterozoic basement below 600 m depth. During the 2003-2004 project reporting year Tasman Resources undertook an intensified round of prospect geophysical surveying, data processing and interpretation, besides carrying out further deep RC and diamond drilling on the Clara St Dora, Titan and Marathon South structures(20 RC holes for 980 m, plus 2483.2 m of rotary precollar/diamond drilling in 3 holes, including 1985.1 m of coring). The geophysical surveys comprised regional (2455 stations) and infill (278 stations) gravity, audio-frequency magnetotelluric (AMT), IP, Mise-a-la-Masse (MALM), and downhole magnetometric resistivity (DHMMR) and transient electromagnetic (DHTEM) methods. Some diamond - seeking exploration was also performed, involving field checks of discrete small magnetic anomalies having the characterisitcs of possible buried kimberlite, plus associated loam heavy mineral sampling to look for kimberlite indicators. All analytical results were negative. For the 2004-2005 project reporting year, the emphasis was mainly on evaluating existing IOCG prospects, which were further examined through applying new geophysical data processing and modelling techniques, assisted by the collection of petrophysical data from drill cores, plus the drilling of another three deep diamond cored holes at the Marathon South prospect for a total recovery of 2327 m of NQ2 core. Some additional ground reconnaissance over several potential intrusive diamond-bearing magnetic features was performed, but heavy mineral analyses of a composite loam sample taken over a genuine such anomaly on EL 2989 were again found to be negative for kimberlitic indicator minerals. During this year Tasman Resources also undertook trial soil gas sampling for SDP (soil desorption pyrolysis) along the 28 km length of an interpreted north-west striking, north-east dipping basin margin fault zone mapped within ELs 3109 and 3209. The intent was to look for hydrothermal geochemical pointers to possible MVT style, Lennard Shelf (WA) type base metal mineralisation that could have formed within the Cambrian Andamooka Limestone proximal to this fault, perhaps through dewatering of Proterozoic sediments during Delamerian inversion of the basin. 240 soil gas samples were collected at 300 m intervals along 48 fault transects spaced 600 m apart. The nature of the regolith present at the sample sites was also noted. Two coherent anomalies were seen in the SDP results, within a generally anomalous region of sand dunes developed over clay pans, that follow for ~6 km along the strike of the fault. During 2005-2006 the licensee mainly carried out petrographic studies of drill cores recovered from its four Marathon South drillholes, besides performing shallow RAB drilling at the Thrust prospect (8 holes for a total penetration of 611 m) to test IP and soil geochemical anomalies on ELs 3123 and 3140. The petrographic work identified the basement brecciated lithologies at Marathon South as essentially being hydrothermally disrupted clastic sediments, in contrast to a previous interpretation which had given them a volcaniclastic origin. The new interpretation places the breccias in a similar genetic setting to the brecciated host greywackes found at Prominent Hill. All of the assay results from the RAB drilling were of uniformly low tenor, with base metal values matching those for average Mesozoic shales. The highly anomalous soil geochemistry recorded in the northern Lake Torrens region is therefore attributed to unusual soil enrichment of base metals arising from the lengthy action of significant weathering and erosion on the regolith profile occurring at Thrust. Some weak chargeability features seen in the accompanying IP and CSAMT data for this prospect are now believed to be due to lithological variations within the Brachina Formation, which underlies a much thinned and ferruginised Bulldog Shale. At the end of the reporting period Tasman Resources was probing back down into its previously completed deep open drillholes at Titan and Marathon South, to try to determine their suitability for logging to acquire downhole temperature gradient measurements, with a view to assessing the region's geothermal energy prospectivity. No other work took place on the subject licence areas for the remainder of 2006.

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About this record

Record No mesac22027
Topic Geoscientific Information
Type of Resource Document
Category Type
Document Type Mineral Company Report - Mineral Exploration
Contributor Haines Surveys Pty Ltd;Adelaide Mining Geophysics Pty Ltd;Zonge Engineering and Research Organization, Inc.;Resource Potentials Pty Ltd;Kelpie Exploration Pty Ltd;Roger Townend and Associates;Value Adding Geophysics;Mitre Geophysics Pty Ltd;SDP Pty Ltd;The University of Adelaide;Pontifex and Associates Pty Ltd
Sponsor Tasman Resources NL
Tenement
Tenement Holder Tasman Resources NL
Operator
Geological Province
Mine Name Airport Claypan prospect;Clara St Dora mine;Junction Dam prospect;West Mount copper workings;OK copper mine;Thrust prospect;Titan prospect;Marathon prospect;Marathon South prospect;Shelf 6 prospect;Peninsula prospect;Zeus prospect;Atlas prospect;Billy Barns prospect
Stratigraphy
Commodity
Notes
Notes: According to the arrangement which has been made by the licensee with PIRSA, this data release comprises both early, licence-specific reports for the subject ELs, plus later joint annual reports for all project licences, covering the stated...

Notes: According to the arrangement which has been made by the licensee with PIRSA, this data release comprises both early, licence-specific reports for the subject ELs, plus later joint annual reports for all project licences, covering the stated period. Includes: - Edgecombe, D.R., December 2003. Review of Cambrian - Neoproterozoic targets [on] Tasman Resources' Lake Torrens Project (Kelpie Exploration Pty Ltd consultant's report). In: Appx 1 of Lake Torrens Project ELs joint annual report to December 2003. - Myers, J.B. and Cooper, M.J., January 2004. Regional diamond prospectivity of Tasman Resources' tenements in South Australia (Resource Potentials Pty Ltd consultants' report). Appx 2a of Lake Torrens Project ELs joint annual report to December 2004. 4 plans, 19 fig, 19 ref. Geographic Locality: Stuart Creek;Porter Hill;Bopeechee;Cadnia Hill;Hedley Hill;White Cliff;Ferguson Hill;Watermans Plain;Saddle Dam;Red Lake;Andamooka North;Todds Dam;Screech Owl Creek;Honeymoon Dam;Coorichina Swamp;Black Wattle Creek;Tarlton Knob;Yarra Wurta Creek;Tutop Ridge;Coward Cliff;Mount James;Piddleeominna Swamp;2002 Titan prospect Aerial Magnetic Survey;2003 Marathon 3/Bopeechee 2/Clara Infill Gravity Survey;2003 Marathon 3/Saddle Hill Infill Gravity Survey;2003 Marathon 3/Amoco Infill Gravity Survey;2003 Titan Gravity Survey;2004 Roxby Downs Gravity Survey;2004 Roxby Downs Extension Gravity Survey Doc No: Env 09786 Drillhole: Western Mining Corp. BD1;ACRC001 - ACRC006;(189840 - 189843);(369107 - 369109);CD1;CRB001 - CRB025;(203190 - 203213);(268476);CD001;();CRC001a - CRC025;(189848);(189850);(189851);(189854 - 189858);(189892 - 189894);(202228 - 202233);(268474 - 268478);CRB026 - CRB030;(203214 - 203218);WMRC001 - WMRC021;(210897);SFRC001 - SFRC005A;(189844 - 189847);(218431);(268479);SFD001;(218429);SFD002;(218430);RC04CSD001 - RC04CSD026;(247689 - 247708);DD04TI007;(232277);DD04TI008;(209917);RC-DD04MS001;(209782);DD05MS002 - DD05MS004;(231063);(231064);(232640);RB06TH001 - RB06TH008;(227885);(227886);(246936 - 246941) Drillhole Unit No: 6237 00275;6237 00299;6337 00117;THROUGH;6337 00160;6338 00098;6338 00196;6437 00045;6437 00061

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Language English
Metadata Standard ISO 19115-3

Citations

Use constraints License
License Creative Commons Attribution 4.0
Persistent identifier https://pid.sarig.sa.gov.au/document/mesac22027
Citation Bryce, N.P.;Hanneson, J.E.;Edgecombe, D.R.;Jeffress, G.M.;Glasson, M.J.;Smith, R.N.;Haines, G.;Thompson, A.D.;Townend, R.;Robertson, W.;Heinson, G.;Kroll, A.;Purvis, A.C. 1909. Bopeechee and Cadnia Hill/Stuart Creek and Porter Hill (The Lake Torrens Project). Data release made at two licences' surrender/two latter licences' fifth partial relinquishment: annual reports and final reports for the period 9/4/1998 to 31/12/2006. Mineral Company Report - Mineral Exploration
https://pid.sarig.sa.gov.au/document/mesac22027

Technical information

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Maintenance and Update Frequency
Geographic Reference GDA2020 (EPSG:7844)
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