1887
Geophysical Signatures of Base Metal Deposits in Victoria
  • ISSN: 2202-0586
  • E-ISSN:

Abstract

Thursdays Gossan Prospect (also known as Victor 1) is the first porphyry copper style mineralisation found in western Victoria. The porphyry system is in the Mount Stavely Volcanic Complex at the intersection of two large faults. Porphyry style Cu-Ag-Mo(-Au) mineralisation is hosted by undeformed, weak to strongly phyllic altered, low-potassium, dacitic, sub-volcanic porphyries and surrounding sediments and volcanics. No true "copper-mineralised quartz stockworks" or economic primary copper mineralisation have been found. Sub-economic mineralisation is disseminated throughout most of the intrusions; the youngest phases are barren. Supergene enrichment of copper occurs as chalcocite in sediments, volcanics and intrusions. The copper mineralisation in the Thursdays Gossan system is low grade and uneconomic.

Electrical surveys (RRMIP) in the 1970s indicated moderately high chargeable and conductive responses coincident with anomalous copper geochemistry. Subsequent RAB and diamond drilling showed the high chargeability to have been from disseminated pyrite and chalcocite and the high conductivity was attributed to the presence of massive pyrite. Geophysical surveys in the 1990s included gravity and airborne electromagnetic surveys. The high conductivity detected in airborne time-domain electromagnetic surveys probably reflects high groundwater salinity within the deeply weathered zone of the alteration system, rather than disseminated sulphides at depth. The gravity low of 2 mGals (20 µms2) is believed to reflect the lower density of the altered/weathered/oxidised rocks. Magnetic surveys over the prospect area were less definitive. Most of the very prospective but weakly magnetic sub-volcanic dacite porphyries could not be distinguished from the nonmagnetic sedimentary rocks.

© ASEG 1999
Loading

Article metrics loading...

/content/journals/10.1071/ASEGSpec11_09
1999-12-01
2026-01-22

  • From This Site

    /content/journals/10.1071/ASEGSpec11_09
    dcterms_title,dcterms_subject,pub_keyword
    -contentType:Journal -contentType:Contributor -contentType:Concept -contentType:Institution
    10
    5
Loading full text...

Full text loading...

References

  1. ANDERSON, H., 1994. North Exploration; Exploration Licences 3167, 3337, 3381, 3408 & 3474, Stavely Project, Victoria: QUESTEM Airborne Geophysical Survey, Interpretation And Logistics Report, Job 1382. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  2. BUCKLAND, G.L., 1985. Mount Stavely Volcanic Complex 1:50 000 geological map. In Buckland, G.L., 1987. Geology and mineral potential of the Mount Stavely Volcanic Complex. Geological Survey of Victoria Report80, 60p.
  3. Donnelly, M. J., 1997. CRA Exploration Pty Ltd, fifth combined annual report for the period ending 6th February 1997 For EL 3167 Hexham, EL 3337 Glenthompson, EL 3381 WiUaura And EL 3474 Wickliffe, Victoria. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  4. Haydon, S.J., 1999. Volcanic hosted massive sulphide prospect near Wickliffe, western Victoria. In A.J. WiUocks, S.J. Haydon, M.W. Asten & D.H. Moore (eds) Geophysical signatures of base metal mineralisation in Victoria, Australia. Geological Survey of Victoria Report 119 and Australian Society of Exploration Geophysicists Special Publication11, pp. 67-80.
  5. HORVATH, H. S., 1993. Peko Exploration Limited: Exploration Licences 2685, 3167, 3337 & 3381, Stavely Project, Victoria: annual report for period ending 6th February, 1993. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  6. HORVATH, H. S., 1994. North Exploration; Exploration Licences 3167, 3337, 3381, 3408 & 3474, Stavely Project, Victoria: annual report for period ending 6th February, 1994. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  7. HORVATH, H. S., 1995. North Limited; Exploration Licences 3167, 3337, 3381, 3408 & 3474, Stavely Project, Victoria: annual report for period ending 6th February, 1995. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  8. MclNNES, P., 1998. North Limited, 6th annual and final report on Exploration Licence 3474 for the period ending 6/02/98. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  9. O’NEILL, W. J., 1991. Peko Exploration Limited: Exploration Licence 2607, Willaura, Victoria: Six monthly progress report for period ending August, 1991. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  10. O’NEILL, W. J., 1992. Peko Exploration Limited: Exploration Licence 2607, Willaura, Victoria: Annual report for period ending 5th February, 1992. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  11. Parkinson, R. G., 1996. CRA Exploration Pty Ltd: fourth combined annual report for the period ending 6th February 1996; EL 3167 Hexham, EL 3337 Glenthompson, EL 3381 Willaura and EL 3474 Wickliffe, Victoria. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  12. ROBERTS, C. J., 1981. Pennzoil of Australia Ltd, Half Yearly Report, Stavely Area, ELs 554, 648 and 649, Period ending June 1981. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  13. Roberts, C. J., 1982. Duval Mining (Australia) Ltd, Stavely Area, Exploration Licences 554, 648 and 649, Final Report. Department of Natural Resources and Environment, Victoria, expired mineral exploration licence reports file (unpubl.).
  14. SPENCER, A. A. S., 1996. Geology, Mineralisation And Hydrothermal Alteration Of Thursdays Gossan Porphyry System, Stavely, Western Victoria. B.Sc. (Hons.) thesis, La Trobe University, Melbourne (unpubl.).
  15. Stuart-Smith, P.G. & Black, L.P., in prep. Willaura 1:100 000 map geological report. Australian Geological Survey Organisation Record.
/content/journals/10.1071/ASEGSpec11_09
Loading
  • Article Type: Research Article
Keyword(s): airborne EM; alteration zone; Ballarat 1:250 000 map sheet; chalcopyrite; conductivity high; dacite; electromagnetic; gravity; magnetic; Mount Stavely Volcanic Complex; oxidised zone; porphyry copper; pyrite; QUESTEM; supergene enrichment; Thursdays Gossan; Victor 1; Victoria

Most Cited This Month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error