Sedimentology and mineral potential of the Birrindudu Basin, Northern Territory

Abstract

A collaborative study commissioned by the Northern Territory Geological Survey (NTGS) under its Resourcing the Territory program and being undertaken by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) seeks to address these gaps in our knowledge. Module 1 of this study, detailing the sedimentological and petrophysical characterisation of the Birrindudu Basin sedimentary succession, has previously been published as NTGS Record 2023-008 (Crombez et al 2023). This Record represents the findings of Module 2 of this study, encompassing the sequence stratigraphic framework and burial history of the Birrindudu Basin, accompanied by analysis of its sediment-hosted copper (Cu) and zinc (Zn) mineral potential.

This Record illustrates that the Limbunya and Wattie groups of the Birrindudu Basin represent five and four 3rd order sequence stratigraphic cycles respectively, with each group spanning a depositional time interval of ca 30-40 million years (Myr). Palaeogeographic reconstructions indicate that the basin depocentre displayed an east-west oriented axis with sedimentary provenance from the north-northeast and the south. Over time, the south-southeastern margin of the basin migrated northwards, indicating basin shallowing in this direction. Conversely, the northern basin margin indicates basin deepening proximal to the Mallapunyah Fault Zone.