Supplementary data to Liebmann et al. (2025) "Extreme crustal fractionation in a Proterozoic chemical hotspot", including K-feldspar and whole-rock Pb isotope data, and apatite U-Pb. https://doi.org/10.1093/petrology/egaf017
This data package comprises feldspar and whole-rock Pb isotopic analyses together with complementary apatite geochronology data from Proterozoic rocks of the Curnamona Province and Gawler Craton, Australia. The dataset was generated to investigate the timing, sources, and evolution of Mesoproterozoic magmatism and its relationship to crustal differentiation and mineral system formation. The data support interpretations of crustal preconditioning, heat production, and metal enrichment processes associated with world-class ore deposits in southern Australia.
The distribution of mineral systems is heterogeneous over space and time, reflecting transient element enrichment within Earth's evolving crust. Australian Proterozoic rocks host some of the world's largest ore deposits, including the Broken Hill Pb-Zn-Ag deposit within the Curnamona Province, and the Olympic Dam Cu-U-Au-Ag super-deposit, within the Gawler Craton, offering key insights into crustal preconditioning for mineralization. New feldspar and whole-rock Pb isotopic data, and complementary apatite geochronology, support a common source for Mesoproterozoic magmatism in the Curnamona Province and Gawler Craton and hence a genetic link between their world-class ore deposits. Exceptionally radiogenic Pb isotope ratios in the Curnamona Province indicate extreme crustal fractionation, likely driven by a positive feedback scenario where crustal anatexis produced melts strongly enriched in heat-producing, incompatible elements, which in turn prolonged anatectic conditions through radiogenic heat production. The resulting granitic rocks may have acted as important metal sources for certain ore deposits, while more generally fostering metal enrichment by providing a persistent heat source for hydrothermal systems. This chemical hotspot may have been triggered by the combination of insulating thickened crust and gravitational destabilization following the assembly of the Nuna supercontinent.
Janne Liebmann, Bryant Ware, Chris Kirkland, Geoff Fraser, David Mole, Brandon Mahan, Ashlea Wainwright, Roland Maas, Janne Liebmann, Bryant Ware (2025): Curnamona Province Pb isotope and U-Pb data. AuScope. (Dataset). https://doi.org/10.82669/7japmx66