Georgina Basin

Sedimentary: dolostone, limestone, shale, sandstone, siltstone.

Epoch Min:

Devonian.

Epoch Max:

Cryogenian (Neoproterozoic).

Age Min:

355 Ma.

Age Max:

850 Ma.

Summary:

A widespread intracratonic basin initiated as part of the Centralian Superbasin and extends east into Queensland. The basin deepens towards the south along the margin with the Aileron Province.

Relationship:

Unconformably overlies Palaeoproterozoic Murphy, Warramunga and Davenport provinces, Palaeo-Mesoproterozoic McArthur and South Nicholson basins and Lawn Hill Platform, and in fault contact with Palaeo-Neoproterozoic Aileron Province. Interpreted to be contiguous with Neoproterozoic to Palaeozoic Wiso and Daly basins that developed as distinct depocentres isolated by basement highs formed from the Cambrian Kalkarindji Province. Unconformably overlain by Mesozoic Carpentaria and Eromanga basins.

Thickness:

Up to 3.7 km.

Economic:

Numerous deposits of sedimentary phosphate including the Wonarah and Ammarroo phosphate deposits. Several lead-zinc occurrences are located along the southern margin. Frequent oil shows throughout the basin.

Metamorphism:

Unmetamorphosed.

Main Reference:

Kruse PD, Dunster JN and Munson TJ, 2013. Chapter 28: Georgina Basin: in Ahmad M and Munson TJ (compilers) ‘Geology and Mineral Resources of the Northern Territory’. Northern Territory Geological Survey, Special Publication 5