Regional targeting of epithermal Au-Ag deposits in a Miocene-Pliocene volcanic terrane: Hauraki goldfield, New Zealand

  • A. B. Christie
  • R. L. Brathwaite
Conference paper

Abstract

Production from adularia-sericite epithermal Au-Ag deposits of the Hauraki goldfield has been mainly from deposits hosted in andesite and dacite (the Kuaotunu and Waiwawa subgroups of the Coromandel Group), although there is potential for low grade large tonnage deposits in rhyolitic rocks (the Whitianga Group). Andesite-hosted and rhyolite-hosted epithermal mineral deposit models are identified, and the former are subdivided into Waiwawa and Kuaotunu subgroup hosted types. Digital regional data sets enable GIS-based regional targeting of prospective areas for the different mineral deposit models, on the basis of host rock lithology and age, lineaments identified in DEM and satellite imagery, aeromagnetic anomalies, gravity anomalies, distribution of known mineral deposits, areas of hydrothermal alteration, and stream sediment and rock geochemical anomalies. Analysis of the paleodepth of epithermal gold deposition in relation to stratigraphy enables definition of unprospective areas where Au-Ag deposits have been substantially eroded or where they are buried under thick cover rocks.

Keywords

Epithermal gold silver Hauraki goldfield exploration targeting 

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References

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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • A. B. Christie
    • 1
  • R. L. Brathwaite
    • 1
  1. 1.Institute of Geological and Nuclear SciencesLower HuttNew Zealand

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