NTGS releases age data from Warburton and Pedirka basins

This geochronology study aims to constrain maximum depositional age of sandstones in the Warburton and Pedirka basins in the southeast Northern Territory. Three samples were taken from wells SHEL27109-1 and McDills 1. Major age peaks occur from ca 1.3 to 1 Ga, with a lesser peak from ca 700 to 500 Ma, similar to previously reported samples of Phanerozoic sandstone from the Amadeus Basin.

The youngest concordant zircon from undivided Warburton Basin sandstone in well SHEL27109-1 is ca 430 Ma, a result that, in conjunction with stratigraphic relationships, constrains the age of the uppermost Warburton Basin intersected by SHEL27109-1 to between Silurian and Carboniferous. A sample of early Permian sandstone of the Crown Point Formation from well McDills-1 contains no concordant zircons younger than Lower Mississippian, a result that is in strong contrast to Permian sandstones of eastern Australia, which are dominated by Permian zircons. This disparity is likely related to distance from the Permian arc system of eastern Australia.

These results form part of the developing detrital zircon dataset for the stacked basins of the southeast Northern Territory. Download NTGS record 2023-003 through GEMIS.