Northern Houtman Sub-basin (Perth Basin) prospectivity study

Last updated:28 August 2020

A key goal of Geoscience Australia’s regional petroleum program is to identify new prospective energy provinces through the acquisition, analysis and delivery of pre-competitive data and associated geological assessments. The northern Houtman Sub-basin is a large frontier depocentre of the Perth Basin, offshore Western Australia, over which data coverage until now has been very poor. In order to better understand the region’s geology and hydrocarbon prospectivity, in 2014-15 the Northern Houtman Sub-basin Project acquired a new regional 2D seismic survey (GA349). The data was processed in 2016. As the seismic survey was carried out under the Australian government’s precompetitive data acquisition program, all acquired and processed data are now publically available from NOPIMS. In 2017 GA undertook a study of the northern Houtman Sub-basin based on the new data. The results of the study suggest that this basin is prospective for oil and gas. Consequently, in 2017 two large acreage blocks were released in the northern Houtman Sub-basin.

The Houtman Sub-basin - An Exploration Frontier

The Houtman Sub‑basin is the largest depocentre in the offshore Perth Basin. It is almost 700 km long, up to 150 km wide and previous studies have suggested it contains a sediment succession over 12 km thick. Only three wells have been drilled in this depocentre, and while seismic coverage in the southern part of the Houtman Sub-basin is of a reasonable density, coverage in the northern sub-basin remained sparse (Jorgensen et al., 2011; Totterdell et al., 2014). In the inboard part of the offshore Perth Basin the presence of an active petroleum system has been demonstrated by the discovery of a commercial oil accumulation at Cliff Head in 2001 and by multiple hydrocarbon shows. However, to date the deep-water part of the Houtman Sub-basin remains largely unexplored (Rollet et al., 2013a, b).

New Pre-competitive Data Acquisition

In 2014-15, Geoscience Australia acquired 3455 km of new 2D seismic data across the northern Houtman Sub-basin (seismic survey GA349) to better image the basin architecture, sedimentary fill and crustal structure of this frontier province (Borissova et al., 2016a, b; Owen, 2016; Southby et al., 2016). The new data have been pre-stack time migrated (PreSTM) and pre-stack depth migrated (PreSDM) and are available for download via the National Offshore Petroleum Information Management System (NOPIMS) or on request from ausgeodata@ga.gov.au. In addition, a multibeam bathymetry dataset was collected as part of this survey and is also available for public download from Geoscience Australia’s website (Spinoccia, 2014).

Structural Architecture and Basin Evolution

In 2015-16, the project conducted a regional interpretation of the legacy 2D seismic data in the Houtman Sub-basin based on ties to petroleum exploration wells in the Abrolhos Sub-basin and southern part of the Houtman Sub-basin. This regional interpretation was then used as a basis for interpreting the new data. Seismic sequences mapped on the new data were used to define tectono-stratigraphic framework specific to the northern Houtman Sub-basin, reflecting changes in stratigraphy in comparison to its southern part (Figure 1; Borissova et al., 2017; Owens et al., 2018a, b).

Results of this study have significantly improved our understanding of the tectonic evolution, structural architecture and major depositional phases of this part of the Australia’s western margin. Interpretation reveals that the northern Houtman Sub-basin depocentre contains up to 19 km of sediments. This includes up to10 km of sediment confined to a series of large half-graben, interpreted to be Permian in age, and between 4 and 6 km of Triassic, Jurassic and Early Cretaceous sequences (Figures 2 and 3; Borissova et al., 2016b, 2017, Southby et al., 2018). Integrated interpretation of the seismic and potential field data revealed that the crust beneath the central part of the northern sub-basin is hyperextended, about 5 km thick (Sanchez et al., 2016; Hall et al., 2017b; Orlov et al., 2017). The highly extended crust beneath the northern Houtman sub-basin is overprinted in the outboard part of the basin by thick volcanic and volcaniclastic successions related to the development of a Large Igneous Province over the Wallaby and Exmouth Plateaus in the Early Cretaceous (Borissova et al., 2015). The combination of highly extended crust with volcanic margin characteristics is quite unusual and requires further investigation.

Figure 1. Tectono-stratigraphic chart for the northern Houtman Sub-basin (Borissova et al., 2017).

Figure 2. Seismic sequences interpreted in the northern Houtman Sub-basin: a) example from GA survey 349, line 1024 ); b) thickness of NH-TR1 sequence (Kockatea Shale equivalent). (Borissova et al., 2017).

Regional Prospectivity Assessment

The newly-interpreted GA349 seismic data provided the basis for the project’s assessment of the petroleum potential of the northern Houtman Sub-basin. The Permian, Triassic and Jurassic successions are likely to contain multiple source rock, reservoir and seal intervals (Figure 1). A variety of potential play types have been identified in the basin, including structural and stratigraphic plays at several stratigraphic levels sourced by different source rocks. The most promising play is a very large Dongara/Kockatea stratigraphic pinchout play, where the Dongara Sandstone is sourced and sealed by the Kockatea Shale (Borissova et al., 2017).

A regional assessment of offshore Perth Basin source rock geochemistry data (Grosjean et al., 2017), suggests that Permian, Triassic and Early Jurassic source rocks have the potential to generate large cumulative volumes of hydrocarbons. Petroleum systems modelling used geochemical characteristics of potential source rocks in the northern Houtman Sub-basin to understand maturity and generation potential in this area. It has shown that Permian, Triassic and Early Jurassic source rocks have generated hydrocarbons, whilst Middle Jurassic‒Cretaceous source rocks remain largely immature (Figure 3; Hall et al., 2017a, b). Petroleum systems modelling results suggest that there is a fair potential for a number of trap types to be charged. However, the full impact of the tectonic and magmatic history of the Houtman Sub-basin on source rock maturity remains poorly constrained. Also, the relationship between the timing of hydrocarbon generation and expulsion with respect to trap formation is critical in this basin and requires further investigation.

Figure 3. Northern Houtman Sub-basin petroleum systems analysis results for selected potential source rocks. (Hall et al., 2017).

Project Outcomes

The acquisition and interpretation of the new pre-competitive data in the northern Houtman Sub-basin significantly improved our understanding of the geology and prospectivity of this frontier area:

  • The basin contains much thicker sedimentary succession (up to 19km) than previously thought;
  • Extrapolated stratigraphy of the basin indicates the presence of several prospective source rock intervals;
  • Basin architecture interpreted from the seismic and geophysical modelling suggests extreme thinning of the crust beneath the main part of the depocentre and the presence of volcanic margin successions in its outboard part;
  • The study has revealed that the breakup on the Houtman-Wallaby margin was diachronous. The breakup unconformity in the inboard part of the basin is Valanginian, whereas in the outboard parts (on the Wallaby Saddle) it is Barremian-Aptian reflecting an almost 20 My later separation of the Wallaby Plateau from India;
  • Petroleum systems modelling results indicate that large amounts of hydrocarbons may have been generated in the basin;
  • Analysis of potential traps has shown than many of them could have been filled with hydrocarbons, provided the interpretation of petroleum systems elements is confirmed by future exploration;
  • Preservation potential for identified plays is good, as very few faults have been reactivated after the breakup, therefore traps filled by hydrocarbons prior to the breakup are likely to be intact.

The systematic workflow applied during the study of this frontier area demonstrated the importance of integrated basin and petroleum systems analysis as a predictive tool for understanding the petroleum resource potential of Australia’s sedimentary basins. For the detailed description of the study please refer to Owens et al, 2018a.

Products and Publications

Data products

Houtman Sub-basin Seismic Survey GA349 - Seismic Field Data - Acquisition report and field tapes for the 3308 km of deep (12s) broadband 2D seismic data collected during the Geoscience Australia Survey (GA0349) in the northern Houtman Sub-basin. Available on request from ausgeodata@ga.gov.au

Houtman Sub-basin Seismic Survey GA349 - Processed Seismic Data - Geoscience Australia Houtman Sub-basin 2D Seismic data (GA0349) processed to PSTM (pre-stack time migrated) and PSDM (pre-stack depth migrated). These data provide the first regional grid over the northern part of the Houtman Sub-basin. Available from NOPIMS or on request from ausgeodata@ga.gov.au

Spinoccia, M, (2014). Houtman Sub-basin 2D Seismic Survey 2014, (GA-0349/Duke10046) - High Resolution Bathymetry Grids. Geoscience Australia, Canberra. - Multibeam bathymetry dataset collected along ship tracks during the Geoscience Australia Houtman Sub-basin 2D Seismic Survey (GA0349)

Reports and news articles

Bodorkos, S., Fitzsimons, I. C. W., Hall, L. S., Sircombe, K. N. and Lewis, C. J. (2016). Beneath the Perth Basin: New U-Pb SHRIMP zircon ages from the Pinjarra Orogen, Western Australia. Geoscience Australia, Canberra. - New age constraints on Pinjarra Orogen basement beneath the Perth Basin.

Grosjean, E., Hall, L.S., Boreham, C.J., Buckler, T., 2017. Source rock geochemistry of the offshore northern Perth Basin: Regional hydrocarbon prospectivity of the offshore northern Perth Basin. Record 2017/18. Geoscience Australia, Canberra. - A review of the offshore northern Perth Basin source rock geochemistry and maturity based on a compilation of publically available data.

Owen, A. (2016). GA349 Houtman 2D Seismic Data-Overview. Geoscience Australia, Canberra. - An overview of the 2D seismic survey GA349 recently acquired by Geoscience Australia in the northern Houtman Sub-basin, with a list of available data products.

Owens, R.J., Borissova, I., Hall, L.S., Bernardel, G., Southby, C., Grosjean, E., and Mitchell, C. (2018a). Geology and prospectivity of the northern Houtman Sub-basin. Record 2018/25. Geoscience Australia, Canberra. - A report detailing the geology and prospectivity of the northern Houtman Sub-basin based on interpretation of the GA349 seismic data.

Sanchez, G., Hall, L.S., Shi, Z., Borissova, I., Pryer, L., Southby, C., Romine, K., Westerman, G., Pietrucha, C. and Kroll, A. (2016). Houtman Sub-basin Geophysical Modelling. Frogtech Pty Ltd, Canberra, Australia. - An integrated geological and geophysical interpretation of the GA349 seismic survey by Frogtech Geoscience and Geoscience Australia.

Southby, C.,Borissova, I.,Owens, R.,Bernardel G.and Morris, R. (2016). Northern Houtman Sub-basin in the spotlight PESA News magazine - An article published in the Petroleum Exploration Society of Australia's monthly magazine, PESA News. The article outlines objectives of the Houtman Sub-basin Prospectivity Study and initial findings of the project.

Conference proceedings

Borissova, I., Southby, S., Bernardel, G., Owens, R., Mitchell, C., Hall, L.S. and Grosjean, E. (2016a). First results from Geoscience Australia 2D seismic survey in the frontier northern Houtman Sub-basin. RIU Good Oil Conference, September 2016, Perth, Australia. Oral Presentation.

Borissova, I., Southby, S., Bernardel, G., Totterdell, J., and Owens, R. (2016b). Northern Houtman Sub-basin Prospectivity: Preliminary Results 2016 APPEA Conference, 5-8 June 2016, Brisbane, Australia. Extended abstract and oral presentation.

Borissova, I., Southby, S., Hall, L. S., Grosjean, E., Bernardel, G., Owens, R., and Mitchell, C. (2017). Geology and hydrocarbon prospectivity of the northern Houtman Sub-basin. 2017 APPEA Conference, 14-17 May 2017, Perth, Australia. Extended abstract and oral presentation.

Borissova, I., Totterdell, J., Southby, S., Owen, K. and Bernardel, G. (2015). Characteristics of the Frontier Northern Houtman Sub-basin Formed on a Magma-Rich Segment of the Western Australian Margin. Search and Discovery Article #10829, AAPG/SEG International Conference & Exhibition, Melbourne, Australia, September 13-16, 2015.

Hall, L.S., Borissova, I., Grosjean, E., Southby, C., Owens, R., Bernardel, G. and Mitchell, C. (2017a). Petroleum Prospectivity of the Houtman Sub-Basin, Offshore Perth Basin, Australia. AAPG Datapages/Search and Discovery Article #90310 ©2017 AAPG/SEG International Conference and Exhibition, London, England, October 15-18, 2017

Hall, L.S., Grosjean, E., Borissova, I., Southby, S., Owens, R., Bernardel, G., and Mitchell, C. (2017b). Petroleum Systems Modelling of the Northern Houtman Sub-basin. 2017 APPEA Conference, 14-17 May 2017, Perth, Australia. Extended abstract and poster presentation.

Hall, L.S., Sanchez, S., Borissova, I., Pryer, L., Southby, C., Shi, Z. and Hackney, R (2017c). Crustal Structure and Tectonic Evolution of the Northern Perth Basin, Australia. AAPG Datapages/Search and Discovery Article #11027 ©2017 AAPG/SEG International Conference and Exhibition, London, England, October 15-18, 2017.

Orlov, C. Hall, L.S., Borissova, I., Southby, C., and Owens, R.J. (2017). Reconstructing the Tectonic Evolution of the Houtman Sub-basin, Western Australia. 2017 Specialist Group in Tectonics and Structural Geology Conference, 8-12 November, Denmark, Western Australia. Poster Presentation.

Owens, R., Borissova, I., Southby, C., Hall, L., Bernardel, G., Grosjean, E. & Mitchell, C. (2018b). Tectono-stratigraphic development of the northern Houtman Sub-basin, Perth Basin. ASEG Extended Abstracts 2018, 1-8.

Sanchez, G., Hall, L.S., Pryer, L., Shi, Z., Borissova, I. and Southby, C. (2018). Unravelling deep structures along a passive-transform margin: insights from an integrated geophysical study of the northern Perth Basin. ASEG Extended Abstracts 2018, 1-6.

Southby, C., Borissova, I., Hall, L.S., Owens, R., Bernardel, G., Grosjean, E., Mitchell, C. and Sanchez, G. 2018. Structural characteristics of northern Houtman Sub-basin, Perth Basin. ASEG Extended Abstracts 2018(1) 1–8.

Related Information

Overview of the Perth Basin’s regional petroleum geology and prospectivity

Other key references

Hackney, R., 2012. Combined marine and land potential-field datasets for the southwest margin of Australia. Geoscience Australia, Record, 2012/37.

Hall, L.S., Gibbons, A.D., Bernardel, G., Whittaker, J.M., Nicholson, C., Rollet, N. and Müller, R.D., 2013. Structural architecture of Australia's southwest continental margin and implications for early Cretaceous basin evolution. In: Keep, M. & Moss, S.J. (Editors), The Sedimentary Basins of Western Australia IV. Proceedings of the Petroleum Exploration Society of Australia Symposium, Perth, WA.

Johnston, S. and Petkovic, P., 2012. Offshore northern Perth Basin 2D and 3D models of depth to magnetic basement. Geoscience Australia, Record, 2012/39.

Jones, A.T., Kennard, J.M., Nicholson, C.J., Bernardel, G., Mantle, D., Grosjean, E., Boreham, C.J., Jorgensen, D.C. and Robertson, D., 2011. New exploration opportunities in the offshore northern Perth Basin. The APPEA Journal, 51, 45-78.

Jorgensen, D. C., Jones, A. T., Kennard, J. M., Mantle, D., Robertson, D., Nelson, G., Lech, M., Grosjean, E. & Boreham, C. J., 2011. Offshore northern Perth Basin Well Folio. Geoscience Australia, Record, 2011/09.

Kempton, R., Gong, S., Kennard, J., Volk, H., Mills, D., Eadington, P. and Liu, K., 2011. Detection of Palaeo-Oil Columns in the offshore northern Perth Basin: Extension of the effective Permo-Triassic Charge System. The APPEA Journal, 51, 377-396.

Norvick, M.S., 2004. Tectonic and stratigraphic history of the Perth Basin. Geoscience Australia, Record, 2004/16.

Pfahl, M.C., 2011. Tectonic subsidence, thermal history and petroleum system modelling of the offshore northern Perth Basin, Western Australia. BSc (honours) thesis, Australian School of Petroleum, University of Adelaide (unpublished).

Rollet, N., Jones, A., Kennard, J.M., Nicholson, C.J., Grosjean, E., Mantle, D., Bernardel, B., Pfahl, M., Greinert, J., Kempton, R., Langhi, L., Zhang, Y., Hall, L., Hackney, R.I., Johnston, S., Boreham, C.J., Jorgensen, D., Robertson, D. and Petkovic, P. 2013a. Northern extension of active petroleum systems in the offshore Perth Basin—an integrated stratigraphic, geochemical, geomechanical and seepage study. In: Keep, M. & Moss, S.J. (Editors), The Sedimentary Basins of Western Australia IV. Proceedings of the Petroleum Exploration Society of Australia Symposium, Perth, WA.

Rollet, N., Nicholson, C., Jones, A., Kennard, J., Grosjean, E. and Bernardel, G. 2013b. New exploration opportunities in the offshore Houtman and Abrolhos Sub-basins, northern Perth Basin, Western Australia. The APPEA Journal, 53, 97-113.

Totterdell, J.M., Hall, L., Hashimoto, T., Owen, K. and Bradshaw, M.T., 2014. Petroleum geology inventory of Australia's offshore frontier basins. Record 2014/09. Geoscience Australia, Canberra.