JSON   RDF   ISO19115/ISO19139 XML

The age and genesis of the Nifty copper deposit: back to the future

A Nd-Sm isochron from apatite in apatite-chalcopyrite veins mostly in the footwall to the Nifty deposit indicates an age of 791 ± 43 Ma. As this apatite is paragenetically associated with chalcopyrite in the veins and in the ore zone, this age is interpreted as the best estimate for the timing of mineralisation at the Nifty deposit. Consideration of the temporal evolution of Nd values precludes deposition of the apatite significantly younger than 800 Ma. The U-Pb systematics of the apatite have been disturbed, resulting mostly in highly scattered arrays that do not have geologic significance. Observations on primary fluid inclusions in quartz from the apatite veins suggest low temperature, relatively high salinity brines. These observations, the geochronological constraints and large ranges in sulphur isotope values suggest that the Nifty deposit formed early, possibly diagenetically, from low temperature, relatively oxidised fluids. This inference is consistent with the original model for the Nifty deposit (Haynes et al., 1993) though less consistent with the tectonic model proposed by Anderson et al. (2001). Structural modelling assuming that mineralisation is early shows that the north trend of ore shoots reported previously on the northeastern limb of the Nifty Anticline is consistent with control by antithetic normal faults developed during basin formation. If this model is correct, these antithetic normal faults would trend west-southwest on the southwestern limb of the Nifty Anticline. This trend has not been adequately drill-tested, and provides scope for additional near-mine exploration on the southwestern limb of the Nifty Anticline.

Data and Resources

Additional Info

Field Value
Title The age and genesis of the Nifty copper deposit: back to the future
Type Dataset
Language English
Licence Creative Commons Attribution 4.0 International
Data Status inactive
Update Frequency notPlanned
Landing Page https://data.gov.au/dataset/bfda643f-03f0-40d7-afa8-bf28c6e2de29
Date Published 2018-11-27
Date Updated 2018-11-27
Geospatial Coverage {"type": "Polygon", "coordinates": [[[121.5, -22.0], [122.0, -22.0], [122.0, -21.5], [121.5, -21.5], [121.5, -22.0]]]}
Jurisdiction Commonwealth of Australia
Data Portal Geoscience Australia CSW Harvester
Publisher/Agency MNHD
comments powered by Disqus
comments powered by Disqus