Summary of results. NTGS laser ablation ICP-MS U-Pb and Lu-Hf geochronology project: Roper Group (McArthur Basin), overlying ungrouped units (Beetaloo Sub-basin), Renner Group (Tomkinson Province), and Tijunna Group (Birrindudu Basin)

Abstract

Sixteen samples of quartz sandstone from the uppermost successions of the informally named greater McArthur Basin in the Northern Territory were selected for laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) U-Pb zircon dating and complementary multi-collector laser ablation inductively coupled plasma mass spectrometry (MC-LA-ICP-MS) Lu-Hf isotope analyses. The 16 analysed samples comprised eight from the Mesoproterozoic Roper Group (McArthur Basin),three from ungrouped Neoproterozoic sedimentary units overlying the Roper Group in the Beetaloo Sub-basin (McArthur Basin), four from the Mesoproterozoic Renner Group (Tomkinson Province), and one from the Mesoproterozoic Tijunna Group (Birrindudu Basin). All samples yielded multiple zircon detrital age populations; the complementary Lu-Hf isotope analyses indicated that these zircons were all derived from multiple juvenile to reworked evolved crustal sources with varying calculated crustal residence ages.