The National Argon Map is an AuScope-funded pilot project (2020–2021). The project aimed to compile a national-scale 40Ar/39Ar geochronology map and to analyse new samples to fill the gaps in national coverage of this dataset. The Geological Surveys of South Australia and New South Wales have selected a series of samples from the Curnamona Province with the aim of providing broad spatial coverage and insight into the thermal evolution of the province. Many of the samples analysed in this study yield complex apparent age spectra which indicate the presence of multiple gas reservoirs, meaning the approach taken here is one of defining upper and/or lower limits in the spectra. The oldest ages obtained in the study derive from igneous rocks in the central Curnamona Province from which biotite and muscovite analyses yield 40Ar/39Ar ages between c. 1623 Ma and c. 1584 Ma, interpreted to reflect cooling after magmatic intrusion. Granitic rocks from the western and eastern Curnamona Province (drillhole Frome 12 and the Mundi Mundi Granite) yield younger ages with a muscovite plateau age of 1472 ± 2.3 Ma and an upper limit age c. 1495 Ma, suggesting that a post-Olarian Orogeny thermal overprint has affected these rocks. Co-existing biotite from these samples have also been modified by younger thermal or microstructural resetting processes and yield disturbed age spectra with ages from c. 1380 Ma to c. 420 Ma, demonstrating the differential effect these younger events can have on micas within the same samples. Ages from samples in the Bimbowrie region in the southern part of the Curnamona Province are all significantly younger than those samples from the more interior regions of the province with biotite ages predominantly in the range c. 480 – 450 Ma, with muscovite analyses yielding a larger range of ages and more discordant age spectra. Biotite therefore appears to record the effects of Delamerian or post-Delamerian cooling in a more complete form than the co-existing muscovite in these samples which have undergone only partial resetting of the 40Ar/39Ar age profiles. Schist samples from the eastern Curnamona Province in New South Wales have variable records of the Delamerian Orogeny, with one sample yielding an age plateau of 493 ± 1.3 Ma and a second being discordant and stepping upwards from a minimum of 578 ± 1.6 Ma to a maximum of 894 ± 5.1 Ma, once again demonstrating that partial thermal and or microstructural resetting related to the Delamerian Orogeny in these samples. K-feldspar age spectra from the Mundi Mundi Granite (New South Wales) and two-mica granite from drillhole YAM 52C (South Australia) are very similar, with lower limits between c. 400 Ma and c. 450 Ma and upper limits at around c. 750 – 760 Ma. The similarity of these age spectra suggest both granites may have experienced similar thermal histories. Potentially, the age spectra reflect burial of the Curnamona Province by Neoproterozoic sedimentary rocks and final exhumation/cooling post-Delamerian Orogeny. The overall pattern of older ages in the more central regions of the Curnamona Province compared to the generally younger ages at the margins may indicate the relative intensity of the effect of the Delamerian Orogeny decreases towards the centre of the province.