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Ceduna Sub-basin

Bids close 21 April 2016

  • Shallow to ultra-deep water depths, ~140–2000 m
  • Multiple potential oil- and gas-prone source rocks
  • Fluvial, lacustrine, deltaic and marine depositional systems
  • Range of structural plays
  • Special Notices apply, refer to Guidance Notes

Release Area S15-1 is located in the Ceduna Sub-basin of the Bight Basin and consists of 254 graticular blocks. Release Area S15-1 lies in the east of the sub-basin and is approximately 85 km offshore and 350 km from Adelaide (Figure 1). There are no wells within the Release Area.

The eastern margin of the Ceduna Sub-basin is characterised by a steep ramp-like geometry and Middle Jurassic–Early Cretaceous half graben. The structural architecture of much of the sub-basin is controlled by a series of generally northwest-oriented, listric normal faults that formed as a result of shale tectonics during deposition of a major delta system in the Cenomanian. Albian–Cenomanian and Turonian–Santonian marine shales, and Cenomanian coaly source rocks are predicted to have charged a range of play types across the Ceduna Sub-basin. Potential plays include fault‑related hanging wall and footwall traps and associated rollovers and dip closures with Cenomanian to Santonian sandstone objectives. Lowside and highside fault-dependent traps, with Campanian Hammerhead Supersequence deltaic sandstone objectives, charged by Turonian and older source rocks are also exploration targets. In addition, there may be some potential for Middle Jurassic–Early Cretaceous half graben plays along the eastern margin of the Ceduna Sub‑basin.

There have been no significant hydrocarbon discoveries in the Ceduna Sub-basin. However the thick sedimentary succession and the evolution of the sub-basin (Figure 2, Figure 3) imply that there is potential for the presence of multiple petroleum systems. In addition to the oil and gas shows observed in wells in the east of the Ceduna and Duntroon sub-basins, evidence for hydrocarbons in the sub-basin is provided by indirect indicators seen on seismic and remote sensing data. Less than 25 km from the Release Area, Greenly 1 (Figure 1) encountered minor gas shows and oil indications in the Late Cretaceous Wigunda Formation (Figure 2). Good quality sandstone reservoirs were also identified within the late Cretaceous–Eocene Pidinga and Potoroo formations. Although the Gnarlyknots 1A well in the central Ceduna Sub-basin (Figure 1) was unsuccessful, a number of secondary indications of charge have been described from analyses of well samples.

Seismic data coverage within the Release Area, and across the eastern Bight Basin more generally, is quite sparse (Figure 4); seismic surveys proposed in existing permits will greatly improve seismic data coverage. At least one well is scheduled to be drilled by Bight Petroleum in EPP 41 to the east of Release Area S15-1. Chevron have guaranteed four wells in EPP 44 and EPP 45, to the west of the Release Area. New seismic acquisition in the region includes the Nerites MC3D Phase 1 survey (8414 km2) that was acquired over Chevron’s exploration permits EPP 44 and EPP 45 in May–June 2014. The Nerites MC3D Phase 2 seismic survey is currently scheduled for 2015 when a further 13 000 km2 of 3D data will be acquired. Bight Petroleum currently have the 3000 km2 Lightening 3D seismic survey over EPP 41 and EPP 42 scheduled for March–May 2015.

Petroleum systems elements

Ceduna Sub-basin

Sources
  • Turonian–Santonian Tiger Supersequence marine shales
  • Cenomanian White Pointer Supersequence coals
  • Albian–lower Cenomanian Blue Whale Supersequence marine shales
Reservoirs
  • Upper Santonian to Maastrichtian Hammerhead Supersequence deltaic and shallow marine sandstones
  • Turonian to Santonian Tiger Supersequence shallow marine sandstones
  • Cenomanian White Pointer Supersequence
  • Valanginian to Albian Bronze Whaler Supersequence
Seals Regional seals
  • Albian–lower Cenomanian Blue Whale Supersequence marine shales
  • Turonian–Santonian Tiger Supersequence marine shales
  • Middle Eocene to Holocene Dugong Supersequence marls and limestone

Intraformational seals

  • Upper Santonian to Maastrichtian Hammerhead Supersequence marine shales
Traps
  • fault-related hanging wall and footwall traps with either rollovers or dip closures, lowside and highside fault-related traps, Middle Jurassic–Early Cretaceous half graben

Infrastructure

The Ceduna Sub-basin is an offshore frontier in South Australia and awaits its first significant hydrocarbon discovery. Current large scale exploration activity in the adjacent permits will require supportive infrastructure which could be expanded to cater for future activities in the 2015 Release Area.

Critical risks

Prior to the most recent phase of exploration, lack of an effective source rock and thus adequate hydrocarbon charge were perceived as the primary exploration risks in the sub-basin. While these risks have been significantly reduced following the identification of a high-quality Cenomanian to Turonian marine source rock, and gas shows at Greenly 1, the presence of mature source rocks and hydrocarbons in the Release Area have yet to be confirmed.

Perceptions of the petroleum prospectivity of the Ceduna Sub-basin are largely derived from the interpretation of seismic data. These interpretations are, however, constrained by limited well control. As a result, there is a degree of uncertainty about the geological/stratigraphic interpretation, particularly for the deeper, pre-Turonian section, and the cross fault seal capacity for structural plays in the Release Area. A lack of knowledge concerning facies evolution across the basin, and particularly across the steeply sloping shelf, as well the impact of deep reservoir burial make it difficult to assess the extent of effective reservoirs and source rock maturity in the Release Area, and across the basin more broadly.

The presence of volcanic and intrusive rocks within and overlying the Upper Cretaceous succession presents a potential risk for petroleum systems and is an issue of concern for seismic data acquisition programs. The closely spaced faulting in the area may also impact upon data acquisition programs.

A key uncertainty for petroleum systems modelling in the region is the thermal history of the basin. Due to the limited amount of good seismic imaging of deep structure and lack of refraction data, the overall structure of the lithosphere is poorly understood. This prevents a detailed understanding of the timing of, and the processes associated with crustal thinning and hence the heat flow history of the basin.

Data sets

Wells Data and Seismic Survey listings for the Ceduna Sub-basin are available in the Supporting Information section.

Geoscience Australia products

Regional geology and seismic

Stratigraphy

Petroleum systems and accumulations

Contact Geoscience Australia’s Sales Centre for more information or to order these reports or products,
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BHP PETROLEUM PTY LTD, 1993. Greenly 1 Well Completion Report, Open File Envelope No. 7456/6 (unpublished).

BLEVIN, J.E., TOTTERDELL, J.M., LOGAN, G.A., KENNARD, J.M., STRUCKMEYER, H.I.M. AND COLWELL, J.B., 2000—Hydrocarbon prospectivity of the Bight Basin—petroleum systems analysis in a frontier basin. In: 2nd Sprigg Symposium – Frontier Basins, Frontier Ideas, Adelaide, 29–30 June, 2000. Geological Society of Australia, Abstracts 60, 24–29.

BOREHAM, C.J., 2009—Organic geochemistry – source rock characterisation. In: Totterdell, J. and Mitchell, C. (eds), Bight Basin geological sampling and seepage survey: RV Southern Surveyor SS01/2007. Geoscience Australia, Record, 2009/24, 36–60.

BOREHAM, C.J., KRASSAY, A.A. AND TOTTERDELL, J.M., 2001—Geochemical comparisons between asphaltites on the southern Australian margin and Cretaceous source rock analogues. In: Hill, K.C. and Bernecker, T. (eds), Eastern Australasian Basins Symposium: a refocused energy perspective for the future. Petroleum Exploration Society of Australia, Special Publication, 531–541.

BRADSHAW, B.E., ROLLET, N., TOTTERDELL, J.M. AND BORISSOVA, I., 2003—A revised structural framework for frontier basins on the southern and southwestern Australian continental margin. Geoscience Australia Record, 2003/03, 89pp.

COWLEY, R., 2001—MkII airborne laser fluorosensor survey reprocessing and interpretation report: Great Australian Bight, Southern Australia. Australian Geological Survey Organisation Record, 2001/18, 53pp.

DAVIES, H.L., CLARKE, J.D.A., STAGG, H.M.J., SHAFIK, S., MCGOWRAN, B., ALLEY, N.F. AND WILLCOX, J.B., 1989—Maastrichtian and younger sediments from the Great Australian Bight. Bureau of Mineral Resources Geology and Geophysics, Report, 288, 62 pp.

EDWARDS, D.S., STRUCKMEYER, H.I.M., BRADSHAW, M.T. AND SKINNER, J.E., 1999—Geochemical characteristics of Australia’s southern margin petroleum systems. The APPEA Journal, 39(1), 297–321.

FEARY, D.A. AND SHIPBOARD PARTY, 1993—Scientific post-cruise report – R/V Rig Seismic cruise 102: geological sampling in the Great Australian Bight. Australian Geological Survey Organisation Record, 1993/18, 149 pp.

GRADSTEIN, F.M., OGG, J.G. SCHMITZ, M.D. AND OGG, G.M. (EDITORS), 2012—The Geologic Time Scale 2012; Volumes 1 and 2. Elsevier BV, 1144pp.

HARRIS, P., RADKE, B., SMITH, A., GLEN, K., ROLLET, N., EXON, N. AND PASSLOW, V., 2000—Marine geological data collected during Southern Surveyor voyage 01/00: eastern Bass Strait and Great Australian Bight. Australian Geological Survey Organisation Record, 2000/43, 90 pp.

HILL, P.J., AND DE DECKKER, P. 2004—AUSCAN seafloor mapping and geological sampling survey on the Australian southern margin by Marion Dufresne in 2003: Final Project Report. Geoscience Australia Record, 2004/04, 144 pp.

HILL, P.J., ROLLET, N. AND SYMONDS, P., 2001—Seafloor mapping of the South-east Marine Region and adjacent waters. AUSTREA-1 final report: Lord Howe Island, south-east Australian margin (includes Tasmania and South Tasman Rise) and central Great Australian Bight. Australian Geological Survey Organisation Record, 2001/08, 141 pp.

HUGHES, M.G., NICHOL, S., PRZESLAWSKI, R., TOTTERDELL, J., HEAP, A., FELLOWS, M. AND DANIELL, J., 2009—Ceduna Sub-basin: environmental summary. Geoscience Australia Record, 2009/09, 140pp.

ION GEOPHYSICAL, 2014—[Web page] Data Library-BightSPAN. http://www.iongeo.com/Data_Library/Asia_Pacific/BightSPAN/ (last accessed 20 December 2014).

KING, S.J. AND MEE, B.C., 2004—The seismic stratigraphy and petroleum potential of the Upper Cretaceous Ceduna Delta, Ceduna Sub-basin, Great Australian Bight. In: Boult, P.J., Johns, D.R. and Lang, S.C. (eds), Eastern Australasian Basins Symposium II. Petroleum Exploration Society of Australia, Special Publication, 63–73.

KRASSAY, A.A. AND TOTTERDELL, J.M., 2003—Seismic stratigraphy of a large, Cretaceous shelf-margin delta complex, offshore southern Australia. AAPG Bulletin, 87(6), 935–963.

MACDONALD, J.D., HOLFORD, S.P., GREEN, P.F., DUDDY, I.R., KING, R.C. AND BACKE, G., 2013—Detrital Zircon data reveal the origin of Australia’s largest delta system. Journal of the Geological Society, 170, 3–6.

MESSENT, B.E.J., 1995—Duntroon Basin, EPP26, Lead Summaries: Platypus-Duntroon, Greenly and outer Basin fairways. BHP Petroleum (Victoria) Pty Ltd. South Australia Department of Mines and Energy, Open File Envelope 8441 (unpublished).

O’NEIL, B.J., 2003—History of Petroleum Exploration. In: O’Brien, G.W., Paraschivoiu, E. and Hibburt, J.E. (eds), Petroleum Geology of South Australia, Vol. 5: Great Australian Bight. http://www.petroleum.pir.sa.gov.au/__data/assets/pdf_file/0006/27366/pgsa5_chapter2.pdf (last accessed 20 December 2014).

SCHOFIELD, A. AND TOTTERDELL, J.M., 2008—Distribution, timing and origin of magmatism in the Bight and Eucla basins. Geoscience Australia Record, 2008/24, 24 pp.

SOMERVILLE, R., 2001—The Ceduna Sub-basin – a snapshot of prospectivity. The APPEA Journal, 41(1), 321–346.

STRUCKMEYER, H.I.M., 2009—[Web page] Ceduna Sub-basin, Bight Basin: results of 3D petroleum systems modelling. https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&catno=69485 (last accessed 20 December 2014)

STRUCKMEYER, H.I.M., TOTTERDELL, J.M., BLEVIN, J.E., LOGAN, G.A., BOREHAM, C.J., DEIGHTON, I., KRASSAY, A.A. AND BRADSHAW, M.T., 2001—Character, maturity and distribution of potential Cretaceous oil source rocks in the Ceduna Sub-basin, Bight Basin, Great Australian Bight. In: Hill, K.C. and Bernecker, T. (eds), Eastern Australian Basin Symposium: A Refocused Energy Perspective for the Future. Petroleum Exploration Society of Australia, Special Publication, 543–552.

STRUCKMEYER, H.I.M., WILLIAMS, A.K., COWLEY, R., TOTTERDELL, J.M., LAWRENCE, G. AND O’BRIEN, G.W., 2002—Evaluation of hydrocarbon seepage in the Great Australian Bight. The APPEA Journal, 42(1), 371–385.

TAPLEY, D., MEE, B.C., KING, S.J., DAVIS, R.C. AND LEISCHNER, K.R., 2005—Petroleum potential of the Ceduna Sub-basin: impact of Gnarlyknots-1A. The APPEA Journal, 45(1), 365–380.

TGS, 2014—[Web page] TGS continues to build backlog with three new multiclient surveys. http://www.tgs.com/News/2014/TGS_continues_to_build_backlog_with_three_new_multi-client_surveys/ (last accessed 20 December 2014).

TOTTERDELL, J.M., BLEVIN, J.E., STRUCKMEYER, H.I.M., BRADSHAW, B.E., COLWELL, J.B. AND KENNARD, J.M., 2000—A new sequence framework for the Great Australian Bight: starting with a clean slate. The APPEA Journal, 40(1), 95–117.

TOTTERDELL, J.M. AND BRADSHAW, B.E., 2004—The structural framework and tectonic evolution of the Bight Basin. In: Boult, P.J., Johns, D.R. and Lang, S.C. (eds), Eastern Australasian Basins Symposium II. Petroleum Exploration Society of Australia, Special Publication, 41–61.

TOTTERDELL, J.M. AND KRASSAY, A.A., 2003—Sequence stratigraphic correlation of onshore and offshore Bight Basin successions. Geoscience Australia Record, 2003/02, 45pp.

TOTTERDELL, J.M. AND MITCHELL, C. (EDITORS), 2009—Bight Basin geological sampling and seepage survey, R/V Southern Surveyor survey SS01/2007: post-survey report. Geoscience Australia Record, 2009/24, 128pp.

TOTTERDELL, J., HALL, L., HASHIMOTO, T., OWEN, K. AND BRADSHAW, M., 2014—Petroleum geology inventory of Australia's offshore frontier basins. Geoscience Australia Record 2014/009, 524 pp.

TOTTERDELL, J.M., STRUCKMEYER, H.I.M., BERNECKER, T. AND KELMAN, A.P., 2013—Bight Basin Biozonation and Stratigraphy Chart 35. Geoscience Australia. http://www.ga.gov.au/corporate_data/76687/Chart_35_Bight_Basin_2014.pdf (last accessed 20 December 2014).

TOTTERDELL, J.M., STRUCKMEYER, H.I.M., BOREHAM, C.J., MITCHELL, C.H., MONTEIL, E. AND BRADSHAW, B.E., 2008—Mid–Late Cretaceous organic-rich rocks from the eastern Bight Basin: implications for prospectivity. In: Blevin, J.E., Bradshaw, B.E. and Uruski, C. (eds), Eastern Australasian Basins Symposium III, Petroleum Exploration Society of Australia, Special Publication, 137–158.

WILLCOX, J.B. AND STAGG, H.M.J., 1990—Australia’s southern margin: a product of oblique extension. Tectonophysics, 173, 269–281.

WOODSIDE, 2004. Gnarlyknots-1A Well Completion Report, Interpretive Data. Woodside Australian Energy report (unpublished).

Figures

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Figure 1

 Bight Basin-Ceduna Sub-basin-figure-1 map image
Structural elements of the Ceduna Sub-basin showing the location of the 2014 and 2015 Release Areas, key well locations and the location of the seismic line shown in Figure 3
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Figure 2

 Bight Basin-Ceduna Sub-basin-figure-2 map image
Upper Paleozoic and Mesozoic stratigraphy and hydrocarbon shows of the Ceduna and Duntroon Sub-basin based on the Bight Basin Biozonation and Stratigraphy Chart 35 (Totterdell et al, 2013). Geologic Time Scale after Gradstein et al (2012)
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Figure 3

 Bight Basin-Ceduna Sub-basin-figure-3 map image
Seismic Line dwgab/20 across the Ceduna Sub-basin. Interpretation after Totterdell et al, 2000. Location of seismic line is shown on Figure 1
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Figure 4

 Bight Basin-Ceduna Sub-basin-figure-4 map image
Seismic and well data in the vicinity of the Release Area in the Bight Basin
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