Timing of Iron Oxide Cu-Au-(U) Hydrothermal Activity and Nd Isotope Constraints on Metal Sources in the Gawler Craton, South Australia

The eastern Gawler craton hosts Australia's premier uranium-bearing iron oxide copper-gold (IOCG) belt, the >500-km-long Olympic Cu-Au-(U) province. In addition to the Olympic Dam Cu-U-Au and Prominent Hill Cu-Au deposits, numerous barren and weakly mineralized IOCG prospects are present in the province. New geochronological data for hydrothermal minerals combined with constraints from host-rock ages demonstrate that alteration and associated IOCG mineralization formed between ~1570 and ~1600 Ma in three districts of the province. This IOCG hydrothermal activity temporally overlaps with magmatism of the Hiltaba Suite and Gawler Range Volcanics. Titanites in paragenetically early magnetite-bearing alteration in the Olympic Dam and Prominent Hill districts yield U-Pb ion probe ages of 1576 ± 5 and 1567 ± 10 Ma, respectively. Molybdenite in veins crosscutting magnetite-biotite and albitic alteration in the Moonta-Wallaroo district have Re-Os ages of 1574 ± 6 and 1599 ± 6 Ma, respectively. These represent minimum ages of the IOCG alteration assemblages in this district. A muscovite 40Ar/39Ar age of 1575 ± 11 Ma provides a minimum age of paragenetically later hematitic alteration in the Olympic Dam district. Neodymium isotope compositions were determined for 44 whole-rock samples from barren and weakly mineralized Cu-Au prospects and host rocks in the Olympic Dam and Prominent Hill districts. The new geochronological framework enables comparison of the Nd isotope data across two IOCG districts at the time of formation of the Olympic Dam deposit (ca. 1590 Ma). Magnetite-rich weakly Cu-mineralized alteration from five prospects yields a relatively narrow range of {varepsilon}Nd(1590) values of -5.8 to -4.1. Both hematite- and magnetite-rich alteration yield generally similar {varepsilon}Nd(1590) values that match values from fresh and weakly altered Paleoproterozoic metasedimentary and metagranitic rocks (-6.6 to -3.5) as well as from most felsic Hiltaba Suite intrusions and Gawler Range Volcanics in the eastern Gawler craton (ca. -6 to -4). These data are consistent with crustal sources for REE and, by implication, for associated copper in the barren and weakly mineralized prospects. Mineralization and alteration in these minor IOCG systems can be geochemically discriminated from the giant Olympic Dam deposit, where greater inputs of mantle-derived REE and other ore components are evident.

Simple

Identification info

Date (Publication)
2007-01-01T00:00:00
Citation identifier
Geoscience Australia Persistent Identifier/https://pid.geoscience.gov.au/dataset/ga/71138

Citation identifier
Digital Object Identifier/http://dx.doi.org/10.2113/gsecongeo.102.8.1441

Cited responsible party
Role Organisation / Individual Name Details
Author

Skirrow, R.G.

 1
Author

Bastrakov, E.N.

 2
Author

Barovich, K.

 3
Author

Fraser, G.L.

 4
Author

Creaser, R.A.

 5
Author

Mark, C.

 6
Point of contact
Role Organisation / Individual Name Details
Custodian

MNHD
Owner

Commonwealth of Australia (Geoscience Australia)
Custodian

Commonwealth of Australia (Geoscience Australia)

 Voice
Topic category
  • Geoscientific information

Extent

N
S
E
W


Maintenance and update frequency
Unknown
Keywords

  • External Publication

  • Scientific Journal Paper

Keywords

  • AU-SA

Australian and New Zealand Standard Research Classification (ANZSRC)

  • Earth Sciences

Keywords

  • Published_External

Resource constraints

Title

Creative Commons Attribution 4.0 International Licence

Alternate title

CC-BY

Edition

4.0

Website

http://creativecommons.org/licenses/

Access constraints
License
Use constraints
License

Resource constraints

Title

Australian Government Security ClassificationSystem

Edition date
2018-11-01T00:00:00
Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification
Unclassified
Language
English
Character encoding
UTF8

Distribution Information

Distributor contact
Role Organisation / Individual Name Details
Distributor

Commonwealth of Australia (Geoscience Australia)

 Voice
OnLine resource

Link to Publication

Link to Publication

Resource lineage

Statement

Unknown

Hierarchy level
Non geographic dataset
Other

External Publication

Description

Source data not available.

Metadata constraints

Title

Australian Government Security ClassificationSystem

Edition date
2018-11-01T00:00:00
Website

https://www.protectivesecurity.gov.au/Pages/default.aspx

Classification
Unclassified

Metadata

Metadata identifier
urn:uuid/a05f7892-f9e2-7506-e044-00144fdd4fa6

Title

GeoNetwork UUID

Language
English
Character encoding
UTF8
Contact
Role Organisation / Individual Name Details
Point of contact

Commonwealth of Australia (Geoscience Australia)

 Voice

Type of resource

Resource scope
Non geographic dataset
Name

nonGeographicDataset

Alternative metadata reference

Title

Geoscience Australia - short identifier for metadata record with

uuid

Citation identifier
eCatId/71138

Metadata linkage

https://ecat.ga.gov.au/geonetwork/srv/eng/catalog.search#/metadata/a05f7892-f9e2-7506-e044-00144fdd4fa6

Date info (Revision)
2018-04-22T08:53:19
Date info (Creation)
2010-10-11T00:00:00

Metadata standard

Title

AU/NZS ISO 19115-1:2014

Metadata standard

Title

ISO 19115-1:2014

Metadata standard

Title

ISO 19115-3

Title

Geoscience Australia Community Metadata Profile of ISO 19115-1:2014

Edition

Version 2.0, September 2018

Citation identifier
https://pid.geoscience.gov.au/dataset/ga/122551

 
 

Spatial extent

N
S
E
W



Provided by

Access to the portal

Associated resources

Not available