eCite Digital Repository

Linking gold mineralization to regional-scale drivers of mineral systems using in situ U-Pb geochronology and pyrite LA-ICP-MS element mapping

Citation

Fielding, IOH and Johnson, SP and Meffre, S and Zi, J and Sheppard, S and Large, RR and Rasmussen, B, Linking gold mineralization to regional-scale drivers of mineral systems using in situ U-Pb geochronology and pyrite LA-ICP-MS element mapping, Geoscience Frontiers, 10, (1) pp. 89-105. ISSN 1674-9871 (2019) [Refereed Article]


Preview
PDF
9Mb
  

Copyright Statement

Copyright 2018 China University of Geosciences (Beijing) and Peking University. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) https://creativecommons.org/licenses/by-nc-nd/4.0/

DOI: doi:10.1016/j.gsf.2018.06.005

Abstract

Proterozoic orogens commonly host a range of hydrothermal ores that form in diverse tectonic settings at different times. However, the link between mineralization and the regional-scale tectonothermal evolution of orogens is usually not well understood, especially in areas subject to multiple hydrothermal events. Regional-scale drivers for mineral systems vary between the different classes of hydrothermal ore, but all involve an energy source and a fluid pathway to focus mineralizing fluids into the upper crust. The Mount Olympus gold deposit in the Proterozoic Capricorn Orogen of Western Australia, was regarded as an orogenic gold deposit that formed at ca. 1738 Ma during the assembly of Proterozoic Australia. However, the trace element chemistry of the pyrite crystals closely resembles those of the Carlin deposits of Nevada, with rims that display solid solution gold accompanied by elevated As, Cu, Sb, Hg, and Tl, surrounding gold-poor cores. New SHRIMP U-Pb dating of xenotime intergrown with auriferous pyrite and ore-stage alteration minerals provided a weighted mean 207Pb*/206Pb* date of 1769 +/- 5 Ma, interpreted as the age of gold mineralization. This was followed by two discrete episodes of hydrothermal alteration at 1727 +/-7Ma and 1673 +/- 8 Ma. The three ages are linked to multiple reactivation of the crustal-scale Nanjilgardy Fault during repeated episodes of intracratonic reworking. The regional-scale drivers for Carlin-like gold mineralization at Mount Olympus are related to a change in tectonic regime during the final stages of the intracratonic 1820-1770 Ma Capricorn Orogeny. Our results suggest that substantial sized Carlin-like gold deposits can form in an intracratonic setting during regional-scale crustal reworking.

Item Details

Item Type:Refereed Article
Keywords:Western Australia, geochronology, xenotime, SHRIMP, LA-ICP-MS, gold mineralization, Capricorn orogen
Research Division:Earth Sciences
Research Group:Geology
Research Field:Geochronology
Objective Division:Expanding Knowledge
Objective Group:Expanding Knowledge
Objective Field:Expanding Knowledge in the Earth Sciences
UTAS Author:Meffre, S (Dr Sebastien Meffre)
UTAS Author:Large, RR (Professor Ross Large)
ID Code:129977
Year Published:2019
Funding Support:Australian Research Council (CE0561595)
Web of Science® Times Cited:3
Deposited By:CODES ARC
Deposited On:2019-01-02
Last Modified:2019-12-10
Downloads:5 View Download Statistics

Repository Staff Only: item control page