Quick facts
Overview
The highly prospective Beetaloo Sub-basin comprises large undeveloped shale gas resources and represents a structural sub-basin of the Palaeoproterozoic McArthur Basin that preserves the thickest sequences of highly prospective Mesoproterozoic Roper Group stratigraphy. Exploration is continuing to define substantial shale gas resources in place, with considerable potential for further unconventional and conventional petroleum resources.
The sub-surface Beetaloo Sub-basin lies within the McArthur Basin and comprises thick sequences of sedimentary and minor volcanic rocks assigned to the following stratigraphic groups or their equivalents: the Palaeoproterozoic Tawallah and McArthur groups, and the Mesoproterozoic Nathan and Roper groups, which hosts the majority of petroleum occurrences.
Information on the geological setting of the McArthur Basin can be found in the McArthur Basin inventory.
Exploration focussed on the shale plays of the Beetaloo Sub-basin has greatly accelerated since 2010 with a number of discovery wells drilled by Origin Energy, Imperial Oil and Gas Pty Ltd, Pangea Resources Pty Ltd, Falcon Oil and Gas Australia Ltd, Santos Ltd and Amour Energy Ltd. Exploration has again rapidly accelerated since 2021 with a number of companies including Empire Energy Ltd, Tamboran Resources Ltd (and Santos Ltd) and Falcon Oil and Gas Australia Ltd (and Origin Energy) announcing significant increases in contingent resources.
Further exploration history can be found in the McArthur Basin inventory.
Petroleum
The Beetaloo Sub-basin is the Northern Territory’s premier shale gas play, with prospectivity increasing as exploration accelerates. The Beetaloo Supersystem contains at least four conventional and unconventional petroleum systems with substantial shale gas resources primarily within the Mesoproterozoic Roper Group. The most prospective shale units in the Roper Group occur within the Velkerri and Kyalla formations. Drilling of the middle Velkerri Formation has demonstrated the consistent presence of gas saturated, quartz-rich shale source rocks that are mature for gas over extensive areas, and which appear to meet all of the physical and chemical parameters for a successful shale gas play (see Revie 2017). The shallower Kyalla Formation also has high potential as a productive shale play, with large areas within the wet gas window.
Download the Shale gas and liquids factsheet PDF (1.0 MB). Additional petroleum potential can be found in the McArthur Basin inventory.
Other energy potential
Minor hydrogen gas shows have been historically recorded from the Beetaloo Sub-basin.
Mineral commodities
For an overview of the mineral prospectivity view the Geology of the Northern Territory Chapter 15 McArthur Basin.
Exploration and appraisal have accelerated since 2020 with a number a number of Contingent Resource estimates announced by key operators in the Beetaloo Sub-basin.
Santos Ltd (75% net share and operator) in joint venture with Tamboran Resources Ltd (25% net share) announced an updated 2C Contingent Resource of 1617 bcf gas for EP161, in the eastern Beetaloo Sub-basin. Successful flow testing from Tanumbirini-2H and Tanumbirini-3H is ongoing.
Tamboran Resources Ltd (38.75% net share) and Bryan Sheffield (38.75% net share) announced that they had agreed to jointly (50% each) acquire Origin Energy’s 77.5% interest in three permits in the central part of the Beetaloo Sub-basin, with Falcon Oil & Gas Ltd remaining a minority owner (22.5%) of the leases (EP 98, 117 and 76). The updated 2C Contingent Resource of 2795 bcf gas for EP 98, 117 and 76 was announced after Netherland, Sewell & Associates, Inc technical report dated 26 August 2022. Fracture stimulation has commenced on Amungee 2H. Drilling of Maverick T436 completed in October 2022 on EP136 and commenced drilling Shenandoah S-1 on EP117 in July 2023. Tamboran recently announced it has secured land at the Middle Arm Sustainable Development Precinct to progress a Concept Select phase for a proposed NTLNG development for a period of 12 months.
Empire Energy Ltd recently announced a 270% increase in 2C Contingent Gas Resource Estimate of 1467 bcf gas from 100% owned and operated EP187 in 2023. Successful flow testing is ongoing in Carpentaria-2H and Carpentaria-3H. Empire Energy also have a 2C Contingent Gas Resource Estimate of 158 bcf gas and 3.5 MMbbl oil from 100% owned and operated EP167 & 168. Empire recently announced production testing has re-commenced on Carpentaria-3H to undertake further analysis to assist in upcoming FInal Investment Decision.
Top End Energy Ltd recently announced the execution of an exploration agreement between the company and the native title holders for EP258, representing becoming a step closer to granting of the first EP in the Territory since 2015.
The following table contains publicly announced best estimate of contingent resources (2C) in the advanced Beetaloo Sub-basin in accordance with the SPE-Petroleum Resources Management System.
| Formation | Permit | Well/s | Resource | Gross Contingent Resources 2C | Operator |
|---|---|---|---|---|---|
| Velkerri Formation | EP167, EP168 | Birdum Creek 1, Tarlee 1, Wyworrie 1 | shale gas (bcf) | 158 | Empire Energy Ltd |
| Velkerri Formation | EP167, EP168 | Birdum Creek 1, Tarlee 1, Wyworrie 1 | oil (MMbbl) | 3.5 | Empire Energy Ltd |
| Velkerri Formation | EP187 | Carpentaria 1, 2, 3, 4 | shale gas (bcf) | 1467 | Empire Energy Ltd |
| Velkerri Formation | EP76, EP98, EP117 | Amungee NW 1,2,3 Kyalla 117, Velkerri 76, Beetaloo 1, Kalala 1, Shenandoah 1 | shale gas (bcf) | 27951 | Tamboran Resources Ltd |
| Velkerri Formation | EP161 | Tanumbirini 1,2,3, Maverick 1, Marmbulligan | shale gas (bcf) | 1617 | Santos Ltd |
1 Gross resource calculated from Tamboran's announced net 38.75% share of resource
Additional resources can be found in the McArthur Basin inventory .
One new well has been spudded in 2023 in EP117 by Tamboran Resources. Four new wells were drilled in the Beetaloo Sub-basin in 2022 with stimulation appraisal of wells ongoing.
The Beetaloo Sub-basin has the most extensive seismic coverage of all NT onshore basins and concentrated exploration wells drilled.
Open file petroleum company reports and all NTGS data and information on the Beetaloo Sub-basin is available from the GEMIS website.
Munson, TJ, 2014 NTGS Report 22: Petroleum geology and potential of the onshore Northern Territory
Williams, B, 2019, NTGS Record 2019-015: Definition of the Beetaloo Sub-basin