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RESEARCH ARTICLE (Open Access)

Petroleum supersystems in the greater McArthur Basin, Northern Territory, Australia: prospectivity of the world’s oldest stacked systems with emphasis on the McArthur Supersystem

Amber J. M. Jarrett A * , Tim J. Munson A , Ben Williams A , Adam H. E. Bailey B and Tehani Palu B
+ Author Affiliations
- Author Affiliations

A Northern Territory Geological Survey, GPO Box 4550, Darwin, NT 0800, Australia.

B Geoscience Australia, GPO Box 378, Canberra, ACT 2601, Australia.

* Correspondence to: Amber.Jarrett@nt.gov.au

The APPEA Journal 62(1) 245-262 https://doi.org/10.1071/AJ21018
Submitted: 17 December 2021  Accepted: 3 February 2022   Published: 13 May 2022

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of APPEA. This is an open access article distributed under the Creative Commons Attribution 4.0 International License (CC BY).

Abstract

This study assesses the prospectivity of the world’s oldest known stacked petroleum systems from the Proterozoic greater McArthur Basin (Northern Territory, Australia), which has immense potential to host both conventional natural gas and oil, in addition to shale-gas accumulations. The Mesoproterozoic succession of the Beetaloo Sub-basin and surrounding region hosts the Territory’s premier shale-gas play and is at an advanced stage of exploration for shale hydrocarbon plays. However, there is also potential for natural gas in older sedimentary packages, with flows and shows reported in underlying Paleoproterozoic successions. At the continent-scale, four regional petroleum supersystems are identified and described in order to provide a platform for consistent nomenclature at the sedimentary package and group level; in ascending stratigraphic order; these are the Paleoproterozoic Redbank and McArthur supersystems, the Paleoproterozoic–Mesoproterozoic Lawn Supersystem, and the Mesoproterozoic Beetaloo Supersystem. The Redbank and Lawn supersystems are newly named and defined, and the Beetaloo Supersystem is renamed from the former Urapungan Supersystem. Eight possible conventional natural gas plays and six shale-gas plays are documented within the McArthur Supersystem, which incorporates Glyde Package successions of the McArthur Basin and the Birrindudu Basin. Petroleum play concepts are also described from this supersystem to assist with assessing the potential for gas resources. A better understanding of the petroleum systems of the greater McArthur Basin is critical to the targeting of areas for geoscience data acquisition in order to facilitate the reduction of exploration search space; and it enables a more rigorous assessment of the potential for conventional and unconventional hydrocarbon resources at local (play) and regional scales.

Keywords: Barney Creek Formation, conventional, geochemistry, Glyde Package, greater McArthur Basin, isotopes, kinetics, natural gas, petroleum plays, petroleum supersystems, pyrolysis, shale gas, unconventional.

Dr Amber Jarrett is a Project Geologist working in the Basin Geoscience team at Northern Territory Geological Survey with over 10 years of experience working in NT basins. Amber graduated with a BSc (Hons), with a major in geology and biology, in 2008 and a PhD in 2014 both from the Australian National University. Prior to the NTGS, Amber worked for 7 years at Geoscience Australia in the Onshore Energy Systems team investigating the geochemistry and petroleum potential of northern Australian basins. Amber is the Chair of the Geological Society of Australia (GSA) NT Division, and a member of the GSA National Governing Council as well as a member of PESA.

Dr Tim Munson is a Senior Geologist at the NTGS with 19 years of experience working in the NT. Tim is a co-author and compiler of the ‘Geology and mineral resources of the Northern Territory’ (2013) and the ‘Petroleum geology of the Northern Territory’ (2014). His current research interests include the stratigraphy, sedimentology, geochronology and tectonics of Proterozoic sedimentary basins in northern and central Australia. Tim obtained his Honours and PhD degrees from the University of Queensland.

Ben Williams is a Senior Geologist with the NTGS, with expertise in structural geology, 3D modelling and basin analysis. Since obtaining his BSc (Hons) in 2001, Ben has worked in both the mining and exploration industry across Australia, Asia and the Pacific. A member of the NTGS Basins Geoscience team, Ben’s current work includes studies into the geological architecture and structural evolution of the Beetaloo Sub-basin, McArthur Basin, South Nicholson Basin and the Lawn Hill Platform.

Dr Adam H. E. Bailey is a Petroleum Geoscientist at Geoscience Australia, with expertise in petroleum geomechanics, structural geology and basin analysis. He graduated with a BSc (Hons) in 2012 and a PhD in 2016 from the Australian School of Petroleum at the University of Adelaide. Working with the Onshore Energy Systems team at Geoscience Australia, Adam is currently working on the flagship Exploring for the Future Program, and he is the Geology Discipline Lead for the Geological and Bioregional Assessment Program.

Tehani Palu is a Geoscientist and Petroleum Systems Analyst at Geoscience Australia, with expertise in burial and thermal history modelling and basin analysis. She gained her Master’s degree with first class honours from the University of Waikato (New Zealand) in 2009 and joined Geoscience Australia shortly after completing her studies. She has since been involved with various projects, including greenhouse gas monitoring for carbon capture and storage, petroleum acreage products in collaboration with the Department of Industry and Science, and petroleum systems modelling within the Onshore Energy Systems Team.


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