Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (5) Citing Articles via Google Scholar Google Scholar Articles by McNaughton, N. J. Articles by Groves, D. I. Search for Related Content GeoRef GeoRef Citation

The Age of the Giant Golden Mile Deposit, Kalgoorlie, Western Australia: Ion-Microprobe Zircon and Monazite U-Pb Geochronology of a Synmineralization Lamprophyre Dike

Neal J. McNaughton^1,, Andreas G. Mueller² and David I. Groves³

¹ Centre for Exploration Targeting, School of Earth and Geographical Sciences, University of Western Australia, Crawley, Western Australia 6009, Australia
² Consultant Geologist, 12a Belgrave Street, Maylands, Western Australia 6051, Australia
³ Centre for Exploration Targeting, School of Earth and Geographical Sciences, University of Western Australia, Crawley, Western Australia 6009, Australia

Corresponding author: e-mail, nmcnaugh{at}cyllene.uwa.edu.au

Open-pit and underground mines in the Golden Mile at Kalgoorlie, Western Australia, have produced more than 1,475 metric tons (t) of gold since 1893. Despite the economic importance of the deposit, the age of the mineralized shear zone array and its temporal relationship to other structures and to porphyry intrusions in the host greenstone terrane are poorly constrained. In this study, the SHRIMP ion microprobe has been used to date zircons and monazites recovered from a chlorite-carbonate–altered, synmineralization lamprophyre dike intruded into sericite-ankerite–altered Paringa basalt below the high-grade Oroya hanging-wall shear zone. Analyses of magmatic-hydrothermal zircons define a weighted mean ²⁰⁷Pb/²⁰⁶Pb age of 2642 ± 6 Ma (n = 37, MSWD = 0.88). Analyses of cogenetic hydrothermal monazites yield a concordant ²⁰⁷Pb/²⁰⁶Pb age of 2637 ± 20 Ma (n = 9, MSWD = 1.8).

The two alteration and/or mineralization ages, determined independently in two different minerals, are inconsistent with recent structural models relating mineralization to the early compressional events of the D₁ to D₄ deformation sequence for the terrane. Instead, they confirm earlier structural models relating mineralization to the postfolding wrench tectonic regime which generated regional sinistral faults (D₃) coeval with mantle-derived lamprophyric and initial felsic magmatism in the middle to lower Archean crust.

This article has been cited by other articles:

				U. Schaltegger Hydrothermal Zircon Elements, February 1, 2007; 3(1): 51 - 79. [Full Text] [PDF]

				R. F. Weinberg, P. Van der Borgh, R. J. Bateman, and D. I. Groves Kinematic History of the Boulder-Lefroy Shear Zone System and Controls on Associated Gold Mineralization, Yilgarn Craton, Western Australia Economic Geology, October 1, 2005; 100(7): 1407 - 1426. [Abstract] [Full Text] [PDF]