The western Warburton Basin is a pericratonic basin containing an early Cambrian ,Ordovician and Devonian succession comparable to the Amadeus Basin. The new SHRIMP U–Pb zircon geochronological results were derived from sedimentary rock chip samples of the western Warburton Basin collected from four petroleum exploration wells (Beachcomber 1, Thomas 1, Simpson 1, Colson 1) located in the southeastern NT, and is the first NTGS data for the western Warburton Basin. The results improve the knowledge of the chronostratigraphy and provenance characteristics of the succession in the NT.
All samples are dominated by Mesoproterozoic detritus (ca 1000–1300 Ma), with a few zircons of Palaeozoic age, and generally sparse older Palaeoproterozoic–Archaean-aged zircons. Samples from the two westernmost wells yielded 238U/206Pb maximum depositional ages of 469 ± 9 Ma (Colson 1) and 394 ± 6 Ma (Simpson 1). Samples from the two easternmost wells yielded older 238U/206Pb maximum depositional ages of 569 ± 10 Ma (Thomas 1) and 506 ± 5 Ma (Beachcomber 1). These data imply that known Devonian (419–359 Ma) stratigraphy of the basin extends at least as far as the Simpson 1 well, but may not extend further east.
This work was undertaken as part of the ongoing NTGS–Geoscience Australia SHRIMP geochronology project under the National Collaborative Framework agreement and Geoscience Australia’s Exploring for the Future Program.
Download NTGS Record 2023-006 through GEMIS.