Browse Basin CO2 Storage Project

Last updated:21 July 2016

Overview

A regional assessment of the geological carbon dioxide (CO2) storage potential of the Browse Basin, offshore northwest Australia was completed by Geoscience Australia between 2013 and 2016. The assessment was part of the Australian Government's National CO2 Infrastructure Plan (NCIP) to accelerate the identification and development of suitable areas for long-term CO2 storage proximal to major emission sources. The Browse Basin was selected, along with two other offshore sedimentary basins (Vlaming Sub-basin of the Perth Basin and Gippsland Basin) and onshore basins in Western Australia and New South Wales, for pre-competitive data acquisition and geological studies as part of this national assessment.

The Browse Basin is a proven hydrocarbon province that hosts significant reserves of gas and condensate, with the majority of accumulations being characterised by high concentrations of CO2 (Figure 1). The last comprehensive publicly-funded regional-scale geological study of the basin was the Browse Basin High Resolution (BBHR) study released by the Australian Geological Survey Organisation (AGSO, now Geoscience Australia) in 1997. Since then, new industry data have been acquired and several CO2 storage site feasibility studies have added to the geological knowledge of the basin.

This study assessed the CO2 storage potential of the basin in the context of existing hydrocarbon prospectivity. As the bulk of commercial hydrocarbon accumulations are hosted within the Jurassic and lowermost Cretaceous successions, this study focused on the Cretaceous succession where there is a reduced risk of overlap between CO2 storage and hydrocarbon resources.

The data used for this study includes information from over 60 wells, regional 2D and 3D seismic reflection surveys, potential field data, as well as existing and newly acquired pre-competitive geochemical, aeromagnetic (Figure 2) and marine environmental data. A revised tectonostratigraphic framework for the basin, standardised to the Geologic Timescale Scale 2012, was a major output of this study (Figure 3).

Regional structure

Regional-scale structural mapping of the Browse Basin included faults associated with major rifting events in the Carboniferous-Permian and Early-Middle Jurassic, Late Triassic compression and inversion, and a period of minor extension in the Late Jurassic-Early Cretaceous. More recent faulting related to the Neogene-Quaternary collision between the Australian and Eurasian tectonic plates was also mapped (Figure 4). The distribution of deep faults revealed different structural styles between the Barcoo and Caswell sub-basins, from multiple relatively small displacement faults in the Barcoo Sub-basin, to fewer large displacement fault systems in the Caswell Sub-basin.

Cretaceous sequence stratigraphy

This study builds on previous work to improve the regional sequence stratigraphic framework for the Cretaceous interval. The K10-K60 supersequences, and the interval comprising the T10, T20 and T30 (part) supersequences, were mapped. Sequence cross-sections and palaeogeographic maps (Figure 5) were produced for the Cretaceous interval to show the distribution of gross depositional facies (GDF). Interpretation of GDF was based on seismic stratal geometries supported by well lithology, well log signature, and seismic facies. Horizon depth maps (Figure 6) and isochore maps (Figure 7) were also produced.

CO2 containment constraints and play fairway mapping

Supersequence cross-sections and palaeogeographic maps revealed three main stratigraphic play types across the Browse Basin: basin-margin, clinoform topset and submarine fan. Basin-margin plays occur throughout the Cretaceous succession where clinoform topsets merge and onlap landward. Clinoform topset plays extend between the basin-margin play and the supersequence shelf edge. The submarine fan plays comprise sandstone-prone basin-floor fans that extend from the toe of slope to the basin floor. The arrangement of reservoir and seal pairs within these play types is the principal constraint on geological CO2 storage.

Other constraints were reservoir depth range, fault distribution (Figure 8), and hydrocarbon resource overlap. Reservoirs within the optimal depth window for economic geological CO2 storage of 800-3200 metres are associated with the K10-K60 supersequences. Structural mapping revealed that deep regional faults provide potential conduits for hydrocarbon charge from Jurassic and deeper petroleum systems along the Heywood Fault System, resulting in potential risk for overlap with the Lower Cretaceous (K10-K40) CO2 storage plays. Plays in the Upper Cretaceous (K60) succession are affected, in part, by Neogene-Quaternary faulting that is optimally orientated for reactivation under the present-day regional stress regime, therefore posing a significant risk to seal integrity. New geochemical analyses have revised the extent and effectiveness of petroleum systems within the Cretaceous succession. Potential overlaps between CO2 storage and hydrocarbon resources have been identified on the Yampi Shelf and in the northern part of the Caswell Sub-basin particularly in association with the K10 supersequence. Containment constraints were mapped for each supersequence to produce play fairway maps (Figure 9).

Common risk element mapping

Composite common risk element maps were compiled by the application of criteria-based traffic-light colour coding of play fairway maps (red=unsuitable, orange=moderately suitable, green=highly suitable). Plays identified as moderately suitable for CO2 storage occur within: 1) K10, K20, K30, lower K40, and K60 clinoform topset plays, 2) K10-K40 stacked basin-margin plays, and 3) K30, K50, and K60 submarine fan plays (Figure 10). Highly suitable plays were not identified by this regional assessment. This outcome is in part because of the current uncertainty about any remaining hydrocarbon prospectivity in the basin.

Outcomes

This study provides a revised basin framework and a regional-scale preliminary prospectivity assessment for the geological storage of CO2 in the Browse Basin. The results will guide future, targeted, site-specific assessments, and identify the main geologic risks warranting further investigation. The study findings will also assist in reducing the risk of overlap between CO2 storage and hydrocarbon resources.

References

AGSO Browse Basin Project Team, 1997. Browse Basin High Resolution Study, Interpretation Report. Record 1997/38. Australian Geological Survey Organisation, Canberra

Gradstein, F.M., Ogg, J.G. & Schmitz, M.D., 2012. The Geologic Time Scale 2012. Elsevier BV, Boston, USA. 1144 pp.

Kelman, A.P., Khider, K., Rollet, N., Abbott, S., Grosjean, E. & Lech, M., 2016. Browse Basin Biozonation and Stratigraphy, Chart 32. Geoscience Australia.

Marshall, N.G. & Lang, S.C., 2013. A new sequence stratigraphic framework for the North West Shelf, Australia. In: Keep, M. & Moss, S.J. (eds.) The Sedimentary Basins of Western Australia 4: Proceedings of Petroleum Exploration Society of Australia Symposium. Petroleum Exploration Society of Australia, Perth. 1-32.

Reports and datasets

AuthorsYearTitle
Edwards, D.S., Grosjean, E., Palu, T., Rollet, N., Hall, L., Boreham, C.J., Zumberge, A., Zumberge, J., Murray, A.P., Palatty, P., Jinadasa, N., Khider, K. & Buckler, T.2016Geochemistry of dew point petroleum systems, Browse Basin, Australia. In: 19th Australian Organic Geochemistry Conference, 4-7 December 2016, Abstract and oral presentation.
Grosjean, E., Edwards, D.S., Boreham, C.J., Hong, Z., Chen, J. & Sohn, J.2016Using neo-pentane to probe the source of gases in accumulations of the Browse and northern Perth basins. In: 19th Australian Organic Geochemistry Conference. Fremantle, 4-7 December 2016. Abstract and poster presentation.
Abbott, S., Khider, K., Kelman, A., Romine, K.2016Facies architecture of the K10 supersequence in the Browse Basin: when sequence stratigraphy meets lithostratigraphy. In: APPEA 2016 Journal and Conference Proceedings.
Kelman, A.P., Khider, K., Rollet, N., Abbott, S., Grosjean, E. & Lech, M.2016Browse Basin Biozonation and Stratigraphy, Chart 32. Geoscience Australia.
Rollet, N., Abbott, S.T., Lech, M.E., Romeyn, R., Grosjean, E., Edwards, D.S., Totterdell, J.M., Nicholson, C.J., Khider, K., Nguyen, D., Bernardel, G., Tenthorey, E., Orlov, C. and Wang, L.2016A regional assessment of CO2 storage potential in the Browse Basin: Results of a study undertaken as part of the National CO2 Infrastructure Plan.  GA Record 2016/17, Canberra, Australia..
Rollet, N., Grosjean, E., Edwards, D., Palu, T., Abbott, S., Totterdell, J., Lech, M., Khider, K., Hall, L., Orlov, C., Nguyen, D., Nicholson, C., Higgins, K. & McLennan, S.2016New insights into the petroleum prospectivity of the Browse Basin: results of a multi-disciplinary study. APPEA Journal, 483-494.
Abbott, S., Caust, D., Rollet, N., Lech, M.E., Romeyn, R., Romine, K., Khider, K. & Blevin, J.2015Seven Cretaceous low-order depositional sequences from the Browse Basin, North West Shelf, Australia: a framework for CO2 storage studies. AAPG ICE, 13-16 September 2015, Melbourne, Australia.
Carroll, A.G., Przeslawski, R. & Tran, M.2015Species identification of worms from grabs - Leveque Shelf (Browse Basin), Western Australia SOL5754 (GA0340). Geoscience Australia.
Edwards, D., Grosjean, E. & Rollet, N.2015Geochemical Characteristics of Oil and Gas Accumulations Used to Define the Petroleum Systems of the Browse Basin. RIU Good Oil Conference, 2-3 September 2015, Fremantle, Australia.
Grosjean, E., Edwards, D.S., Kuske, T.J., Hall, L., Rollet, N. & Zumberge, J.E.2015The source of oil and gas accumulations in the Browse Basin, North West Shelf of Australia: a geochemical assessment. AAPG ICE, 13-16 September 2015, Melbourne, Australia.
Rollet, N., Abbott, S.T., Lech, M.E., Caust, D., Romeyn, R.2015Cretaceous Stratigraphic Play Fairways and Risk Assessment in the Browse Basin: Implications for CO2 Storage and Hydrocarbon Prospectivity, AAPG ICE, 13-16 September 2015, Melbourne, Australia.
Howard, F.J.F., Nicholson, C., Bernardel, G., Carroll, A.G., Grosjean, E., Hackney, R., Lech, M., Melrose, R., Nichol, S.L., Picard, K., Radke, L.C., Rollet, N., Romeyn, R., Siwabessy, P.J.W.2015A marine survey to investigate seal integrity between potential CO2 storage reservoirs and seafloor in the Caswell Sub-basin, Browse Basin, Western Australia: GA0345/GA0346/TAN1411 - post-survey report. GA record 2016/005, Canberra, Australia.
Hackney, R., Romeyn, R. & Orlov, C.2015Interpretation and modelling of new Browse Basin airborne magnetic data for igneous rocks and basement. ASEG-PESA 2015, 15-18 February 2015, Perth, Western Australia.
Lech, M.E., Rollet, N., Caust, D. & Romine, K.K2015Evolution of early Campanian to Maastrichtian supersequences in the Caswell Sub-basin - implications for CO2 storage and hydrocarbon entrapment. AAPG ICE, 13-16 September 2015, Melbourne, Australia.
Nicholas, W.A.2015Seabed environments and shallow geology of the Leveque Shelf, Browse Basin, Western Australia: seabed sediment laser measured grainsize data. Geoscience Australia, Canberra.
Nicholson, C., Bernardel, G., Carroll, A.G., Grosjean, E., Hackney, R., Howard, F.J.J. Lech, M., Melrose, R., Nichol, S.L., Picard, K., Radke, L.C., Rollet, N., Romeyn, R., Spinoccia, M., Siwabessy, J., Trafford, J.2015Caswell Sub-basin, Browse Basin CO2 data package, Geoscience Australia, Canberra, Australia.
Nicholson, C., Romeyn, R., Lech, M., Abbott, S., Bernardel, G., Carroll, A., Caust, D., Grosjean, E., Hackney, R., Howard, R., Nichol, S., Radke, L., Rollet, N., Siwabessy, J. & Trafford, J.2015Browse Basin 2014 marine survey - investigating containment for potential Late Cretaceous CO2 storage plays. AAPG ICE, 13-16 September 2015, Melbourne, Australia.
Edwards, D.S., Grosjean, E., Kuske, T., Le Poidevin, S., Chen, J., Hong, Z., Boreham, C.J., Rollet, N. & Zumberge, J.2014Redefining the petroleum systems of the Browse Basin. Program and Abstracts. AOGC2014: the 18th Australian Organic Geochemistry Conference, 30 November-2 December 2014, Adelaide, South Australia.
Hackney, R. & Costelloe, M.2014New geophysical data for CO2 storage and hydrocarbon prospectivity in the Browse Basin, Geoscience Australia Insights, Canberra, Australia.
Hackney, R. & Costelloe, M.2014New Airborne Magnetic Data Covering the Browse Basin, Preview Newsletter, April 2014, p20-21.
Geoscience Australia2014Browse Basin Marine Survey, 2014 (GA-0345,GA-0346 and TAN1411) - High Resolution Bathymetry Grids WMS.
Jones, L.E.A.2014Seabed environments and shallow geology of the Leveque Shelf, Browse Basin, Western Australia - Processed multichannel sub bottom profiler data.
Picard, K., Nichol, S., Hashimoto, T., Carroll, A.G., Bernardel, G., Jones, L.E.A., Siwabessy, P.J.W., Radke, L.C., Nicholas, W.A., Carey, M., Howard, F.J.F., Tran, M. & Potter, A.2014Seabed environments and shallow geology of the Leveque Shelf, Western Australia SOL5754 (GA0340) post survey report, GA record 2014/010, Canberra, Australia.
Radke, L.C. & Watson, T.2014Seabed environments and shallow geology of the Leveque Shelf, Browse Basin, Western Australia - Carbonate and specific surface area of seabed sediments. Geoscience Australia, Canberra.
Siwabessy, J. & Picard, K.2014Leveque Shelf Browse Basin Marine Survey (GA-0340/SOL5754) (NCIP Program) - High Resolution Multibeam Acoustic Backscatter Grids. Geoscience Australia, Canberra.
Spinoccia, M.2014Browse Basin Leveque Shelf Environmental Survey (GA-0340/ SOL5754) (NCIP Program) - High Resolution Bathymetry Grids. Geoscience Australia, Canberra.
Przeslawski, R., Carroll, A.G. & Tran, M.2013Underwater video and still images from the Browse basin (GA340/SOL5754). Geoscience Australia, Canberra.