1. Release Areas AC17-5 and W17-3, Northeastern Caswell Sub-basin, Browse Basin, Western Australia

2. Highlights

Bids close 22 March 2017  Situated between the Ichthys and Crux gas accumulations, and outboard of the Cornea- Focus oil and gas accumulations  Close to the recently completed Ichthys gas pipeline  Quality reservoirs and seals, multiple potential oil- and gas-prone source rocks, and active petroleum systems  Further guidance available, refer to 2017 Special Notices The contiguous Release Areas W17-3 and AC17-5 are located in the northeastern Caswell Sub-basin (Browse Basin), 220 km off the northwest coast of Western Australia, in water depths of 30–350 m (Figure 1). Release Area W17-3 consists of 39 graticular blocks (2715 km2). Release Area AC17-5 comprises 43 graticular blocks (3510 km2). The Browse Basin comprises six major tectonostratigraphic phases; middle Carboniferous–early Permian extension, early Permian to Late Triassic thermal subsidence, Late Triassic to Early Jurassic inversion, Early to Middle Jurassic extension, Late Jurassic to middle Miocene thermal subsidence, and middle Miocene to Holocene inversion (Figure 2). The Caswell Sub-basin is a Browse Basin depocentre that contains up to 15 000 m of Paleozoic to Cenozoic sediments (Figure 2). Contiguous Release Areas W17-3 and AC17-5, referred to hereafter simply as the Release Areas, are situated over the Heywood Graben in the northeastern Caswell Sub- basin, between the Ichthys and Crux gas accumulations, and outboard of the Cornea- Focus oil and gas accumulations (Figure 1). Figure 3 is an interpreted seismic path over the southern part of the Release Areas. Buccaneer 1 (Figure 4) is one of the few wells in the region to intersect the Triassic, and provides an indication of the stratigraphy of the Release Areas.

AUSTRALIA 2017 Offshore Petroleum Exploration Acreage 1 Release 1

DISCLAIMER: This information has been provided as a guide only. Explorers should not rely solely on this information when making commercial decisions. For more information see - http://petroleum-acreage.gov.au/2016/disclaimer. Image courtesy of Chevron Australia Figure 5 depicts some important play types in the Caswell Sub-basin, and their lithostratigraphic and sequence stratigraphic context. The most common exploration play within the Release Areas is extensional fault blocks and associated roll-over anticlines. The main reservoir units associated with this play are the Lower-Middle Jurassic Plover Formation, and the lowermost Cretaceous Brewster Member, but also include the Jurassic Montara Formation and the Triassic Nome and Pollard formations. The Plover Formation is an important reservoir in the Ichthys and Crux gas fields, while the Brewster Member is the main reservoir in the Ichthys gas field.

Lower Cretaceous M. australis sands (informal, Echuca Shoals Formation) and D. davidii sands (informal, lower Jamieson Formation), both of which are shallow marine deposits, have received attention from explorers within the Release Areas, in plays that typically involve ‘drape folding’ over structural highs. Other Lower Cretaceous sandstone intervals are regarded as submarine fan deposits (e.g. Asterias Member at Kalyptea 1 ST1). The Upper Cretaceous Puffin Formation, which includes submarine fan deposits, has also been targeted.

2 Reservoirs are sealed by the regional Upper Jurassic–Lower Cretaceous upper Vulcan and Lower Cretaceous Echuca Shoals and Jamieson formations. The thickness of these seals ensures fault seal for the underlying reservoirs. Sections within the lower Vulcan Formation also form adequate seals for Plover Formation reservoirs. Potential intraformational seals occur within the Plover Formation, while marls and mudstones provide potential seals for submarine fan sandstones in the Puffin Formation. Figure 6 shows the well and seismic data coverage in the region. Three wells lie within Release Area AC17-5 and 5 wells lie within Release Area W17-3. Numerous wells lie in the near vicinity of both Release Areas. Partial 3D seismic coverage of Release Area AC17-5 is provided by the North Browse TQ, Arlo, Canis, Coppernicus and Octanis surveys. Almost complete 3D seismic coverage of Release Area W17-3 is provided by the Adele Trend TQ and Canis surveys. Extensive 2D seismic coverage exists over both Release Areas.

Petroleum systems elements

North-eastern Caswell Sub-basin Sources  Aptian–Cenomanian marine Jamieson Formation (oil-prone)  Valanginian–Aptian marine Echuca Shoals Formation (oil-prone)  Callovian–Valanginian marine Montara and Vulcan formations (oil- prone)  Lower–Middle Jurassic fluvio-deltaic Plover Formation (oil- and gas- prone) Reservoi  Upper Cretaceous shallow marine and submarine fans of the Puffin and rs Fenelon formations  Albian lower to upper shoreface marine sandstones of the Heywood Formation  Aptian marine D. davidii sands (informal) of the lower Jamieson Formation  Barremian shallow marine M. australis sands (informal) and submarine fans of the Asterias Member (both Echuca Shoals Formation)  Upper Jurassic–Lower Cretaceous marine sandstones of the upper Vulcan Formation (including the Berriasian Brewster Member)  Middle–Upper Jurassic marine Montara and lower Vulcan formations  Lower–Middle Jurassic fluvio-deltaic sandstone of the Plover Formation  Upper Triassic deltaic marine sandstone of the Nome Formation Seals Regional Seals  Lower Cretaceous marine Echuca Shoals and Jamieson formations  Upper Jurassic–Lower Cretaceous marine Vulcan Formation Intra-formational Seals  Upper Cretaceous marine Puffin Formation  Lower–Middle Jurassic fluvio-deltaic Plover Formation Traps  Triassic, Jurassic, and earliest Cretaceous horsts, tilted fault blocks,

3AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 3 and roll-over anticlines associated with Jurassic extension  Compactional or fault propagation ‘drapes’ over extensional structural highs  Cretaceous submarine canyon fill and basin floor fans

Well control for AC17-5

Asterias 1 ST1 (1987) Asterias 1 ST1 was drilled by BHP Petroleum to test Berriasian sandstone (i.e. Brewster Member) within a faulted anticline, above a tilted fault block. Secondary targets were Maastrichtian and Tithonian sandstone intervals. The well reached a TD of 4402 m in the Upper Jurassic. Hydrocarbon indications were present in three major sandstone units (I, II and III). Unit I, from 3 413 to 3499 mRT (i.e. Asterias Member) yielded good porosities with a maximum of 25% but hydrocarbon shows were regarded as insignificant. RFT results confirmed that this unit was water saturated. Unit II, from 3647 to 3729 mRT (i.e. undifferentiated Echuca Shoals Formation) yielded porosities that averaged 13% and minor hydrocarbon shows but log evaluation indicated that the entire unit was water bearing. Unit III, from 4291 to 4381 mRT (i.e. undifferentiated Upper Vulcan Formation) yielded porosities up to 20% and shows indicated that significant residual hydrocarbons were present. Geochemical extraction on SWC 149 (claystone) at 4325 mRT indicated that the residual hydrocarbon was oil. Petrophysical analysis of Unit III, however, indicated that water saturation was sufficiently high that well testing was not performed.

Kalyptea 1 ST1 (1989) Kalyptea 1 ST1 tested sandstones within the Asterias Member (Echuca Shoals Formation) and Brewster Member (upper Vulcan Formation) within a four-way dip anticlinal structure. The anticline was interpreted as a compactional structure developed prior to the Miocene inversion. Vertical relief of closure at the base Cretaceous level was estimated at over 100 m. The of TD of 4575 mKB was reached in the Berriasian (C. delicata Dinocyst Zone). The Puffin Formation was a secondary target. Minor to good hydrocarbon shows were recorded during drilling from all sandstones below 4100 mKB. Sandstone intervals within the Asterias Member yielded porosities of approximately 11%. DST #2, performed within this interval, flowed 65 bbls (10.34 m3) of formation water and indicated a permeability of 4 mD. A cased hole RFT performed in this interval recovered 65.6 cu ft (1.84 m3) of gas, 0.95 litres of condensate, and 12.3 litres of formation water/filtrate. This test was regarded as unreliable because of the extremely high drawdown pressures exerted on the formation during testing. Three sandstone packages within the upper Vulcan Formation (attributed to the Brewster Member) were divided into upper, middle, and lower packages, with average porosities respectively of 12%, 7% and 8%. DST #1, performed in the middle package, failed to flow and indicated little or no permeability. A cased hole RFT run in the lower package indicated permeabilities on the order of microdarcies. The Lower Cretaceous (Brewster, Asterias) sandstones are poor quality reservoirs that contain only residual hydrocarbons. Petrophysical analysis of the Puffin Formation sandstones returned porosities between 17% and 24%, but no tests were performed on this interval because of the absence of shows during drilling.

4AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 4 Copernicus 1 ST1 (1993) Mobil Exploration and Producing Australia Pty Ltd drilled Copernicus 1 ST1 to a TD of 2750 mRT. The primary objective of the well was a predicted Late Jurassic (Oxfordian to Kimmeridgian) sandstone package faulted against the main basin-bounding fault system. Cross-fault seal was interpreted to be provided by Permian and Triassic units (Mount Goodwin and Hyland Bay formations) and vertical seal was predicted to be provided by the Lower Cretaceous Echuca Shoals Formation. The Middle Triassic Pollard Formation was intersected at the level of the primary objective. Reservoir quality was adequate (12.4% average porosity based on petrophysical analysis). Total gas levels recorded while drilling ranged between nil and very low, and trace oil shows were recorded from the basal Echuca Shoals Formation and Pollard Formation sandstones. In the absence of significant hydrocarbons, well testing was not performed.

Well control for W17-3

Heywood 1 (1974) Heywood 1 was drilled by B.O.C. of Australia Limited to evaluate the hydrocarbon potential of a Permo-Triassic–Middle Jurassic horst block. The well was drilled in 35 m of water and reached a total depth of 4572 mRT. High gas readings and traces of live oil were encountered in the Lower Cretaceous to Lower Jurassic succession (Echuca Shoals and upper Vulcan formations). Two wireline formation tests were run to test Kimmeridgian– Oxfordian and Hauterivian–Berriasian sandstones, but no hydrocarbons were recovered. Good oil shows in the Lower–Middle Jurassic section could not be tested due to mechanical problems.

Buccaneer 1 (1990) Buccaneer 1 was drilled by Shell Development (Australia) Pty Ltd. The well was designed to test Middle–Upper Jurassic Plover and Late Jurassic lower Vulcan Formation fluvio- deltaic sandstones, in a fault controlled roll-over closure, on the downthrown side of the basin margin fault. The well was drilled in 156 m of water and reached a total depth of 3574 mRT. The primary Middle Jurassic objective was absent immediately below the ‘main’ unconformity. However, fair hydrocarbon shows were encountered in the Upper Vulcan Formation (Tithonian–Berriasian) and the Pollard Formation (Middle Triassic), consistent with the presence of residual oil.

Adele 1 (1998) Adele 1 was drilled by Shell Development (Australia) Ltd to test Middle-Upper Jurassic reservoirs associated with the Adele structure. Aptian-Albian sandstones were secondary objectives. The well was drilled to a TD of 4822 mDF. Within the primary target, Upper Jurassic sands of the lower Swan Formation (i.e. lower Vulcan Formation) were tight, and the Middle Jurassic section consisted entirely of volcanics. Gas with a condensate/gas ratio of approximately 331 cm3/m3 was recovered by FMT from glauconitic and calcareous sandstones at the base of the Upper Heywood (Jamieson) Formation. Oil shows were recorded in both the basal Upper Heywood and Lower Heywood (Echuca Shoals) Formations.

5AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 5 Rondo 1 (2007) Shell Development (Australia) Pty Ltd drilled Rondo 1 to a of TD of 3566 m after intersecting the target D. davidii sands (informal, Jamieson Formation) and M. australis sands (informal, Echuca Shoals Formation), with both described as a series of laterally continuous nearshore to inner shelf deposits. Four-way dip closure occurs at both levels and is fault-controlled at the M. australis level. Hole stability problems prevented sampling and wireline logging over the target interval. No ditch gas or fluorescence was recorded. Petrophysical analysis of cuttings revealed that the target sandstones were low net to gross, of low porosity, and water wet.

Trio 1 (2007) Trio 1 was drilled by Shell Development (Australia) Pty Ltd to a TD of 2177 mMDRT to test a combined structural and stratigraphic prospect within the lower Puffin Formation. Good quality potential reservoir sandstones were intersected in the target interval, and intra-Puffin shales provided good top seal. However, the Puffin Formation sandstones were water wet. Gas log readings were very low throughout the well and no fluorescence was observed in ditch cuttings. Geochemical analyses were not conducted.

Minuet 1/Intermezzo 1 (2009) Minuet 1 was drilled by Shell Development (Australia ) Pty Ltd to a TD of 4414.5 mMDRT. The well was designed to test a small four-way dip closure at the level of the Berriasian part of the Swan Formation (i.e. Brewster Member of the upper Vulcan Formation). The well was drilled outside of closure to test the potential for stratigraphic trapping against the Adele High. Petrophysical analysis of the upper Swan Formation objective indicates that the well intersected low (ca. 30%) gas saturated argillaceous sandstones with an average log porosity of 9.4%. Formation pressure testing confirmed that the argillaceous sandstones were too tight to flow. Intermezzo 1 is a deviated well from Minuet 1. The well was kicked off at 4068.0 mMDRT and was drilled to a total depth of 4763.0 mMDRT. Tithonian sandstone of the middle Swan Formation (i.e. upper Vulcan Formation) was the primary objective of Intermezzo 1. The middle Swan Formation objective, comprising argillaceous sandstone interbedded with silty claystone, had a gross interval of 40.8 m with 13.2 m net pay, and an average porosity of 7.8%. Petrophysical analysis determined that all sands encountered over the primary objective were water bearing. Intermezzo 1 intersected a 23.3 m gross gas column (4373.5- 4 396.8 mMDRT) within the Swan Formation containing low porosity and low gas saturated tight sands.

Infrastructure and markets Two LNG projects are in development in the Browse Basin. First gas for the Prelude (WA-44-L) FLNG Project (encompassing the Prelude and Concerto accumulations) is likely to commence in 2018. The Prelude Floating LNG Project is located about 475 km northeast of Broome, Western Australia and near the Ichthys Field.The Ichthys (WA-50-L) LNG Project pipeline to Blaydin Point was completed in November, 2016 and first gas is anticipated in the latter half of 2017.

6AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 6 The proposed Browse Floating LNG project, encompassing the Torosa (WA-30-R), Brecknock (WA-29-R and WA-32-R) and Calliance (WA-28-R, WA-31-R) accumulations was deferred in March 2016 . The title holders are actively considering new development options. The proposed Crux (AC/RL9) gas and liquids project remains in the concept development stage.

Critical risks Proven petroleum systems and migration pathways have been established in the region of the combined release area. Success relies on the identification of additional traps with access to charge from effective source rocks. Reservoir quality is a potential risk, particularly the occurrence of volcanics within the Plover Formation. Trap integrity is a risk due to fault reactivation in the late Miocene-Pliocene. A long vertical migration pathway is required for hydrocarbons sourced from the Echuca Shoals Formation through to the Puffin reservoirs. The viability of fault migration to Puffin reservoirs remains unresolved. Drilling risks associated with the Cenozoic succession are well known in the Caswell Sub-basin. These include severe mud loss in the Basset and Oliver formation carbonate rocks, and hole instability associated with loose sand in the Grebe Formation (i.e. Woodbine Group).

NOPIMS data Data relating to the Release Areas can be accessed through the National Offshore Petroleum Information Management System (NOPIMS), an online data discovery and delivery system for all Australian offshore petroleum wells and seismic surveys. http://www.ga.gov.au/nopims

Marine and environmental information

Release Area W17-3 characteristics Release Area W17-3 is located over slope, terrace and shelf geomorphic features in water depths of approximately 30−320 m, 170 km from the nearest coast to the southeast where the Prince Regent National Park is located. Seabed sediment is generally muddy in texture. Specific hazards are few, except for tropical cyclones.

Commonwealth marine reserves Release Area W17-3 is located 65 km north east of the Kimberley Commonwealth Marine Reserve, 81 km south of Cartier Island and 123 km south east of Ashmore Reef.

7AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 7 Key ecological features Key ecological features overlapping Release Area W17-3 include the ancient coastline at the 125 m depth contour and the continental slope demersal fish communities. Ashmore Reef, Cartier Island and surrounding Commonwealth waters are 82 km to the north of the area. The carbonate bank and terrace system of the Sahul Shelf is 93 km east of the area (National Conservation Values Atlas, 2016).

Biologically important areas Release Area W17-3 includes the biologically important area for Whale Shark foraging along the 200 m contour (National Conservation Values Atlas, 2016). The Atlas of Living Australia (www.ala.org.au) and the North-West Atlas (www.northwestatlas.org) provide further information and visualisations concerning animals and plants recorded from the release area, including Threatened or Listed species.

Heritage No shipwrecks are listed in the area.

References and Information Resources National Conservation Values Atlas http://www.environment.gov.au/webgis- framework/apps/ncva/ncva.jsf Atlas of Living Australia http://www.ala.org.au/ Ashmore Reef Commonwealth Marine Reserve https://www.environment.gov.au/topics/marine/marine-reserves/north-west/ashmore Cartier Island Commonwealth Marine Reserve https://www.environment.gov.au/topics/marine/marine-reserves/north-west/cartier Kimberley Commonwealth Marine Reserve https://www.environment.gov.au/topics/marine/marine-reserves/north-west/kimberley Commonwealth Fisheries http://www.afma.gov.au/fisheries/ North-West Atlas (www.northwestatlas.org) Western Australian Fisheries http://www.fish.wa.gov.au/Fishing-and- Aquaculture/Commercial-Fishing/ Shipwrecks http://www.environment.gov.au/heritage/historic-shipwrecks/australian-national- shipwreck-database

Release Area AC17-5 characteristics Release Area AC17-5 is located over slope, terrace and shelf geomorphic features, in water depths of approximately 120−350 m, 173 km from the nearest coast to the southeast where Prince Regent National Park is located. Seabed sediment is generally muddy in texture. Specific hazards are few, except for tropical cyclones.

8AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 8 Commonwealth marine reserves Release Area AC17-5 is located 73.5 km northeast of the Kimberley Commonwealth Marine Reserve, 45 km south of Cartier Island, and 82 km southeast of Ashmore Reef.

Key ecological features Key ecological features overlapping the area include the ancient coastline at the 125 m depth contour and the continental slope demersal fish communities. Ashmore Reef, Cartier Island and surrounding Commonwealth waters are 45 km to the north of the area. The carbonate bank and terrace system of the Sahul Shelf is 72 km east of the area (National Conservation Values Atlas, 2016).

Biologically important areas Release Area AC17-5 includes biologically important areas (National Conservation Values Atlas, 2016): Foraging and breeding area for seabirds (overlapping, White-tailed Tropicbird, to the north west; Greater Frigatebird, Lesser Frigatebird, Red-footed Booby, Wedge-tailed Shearwater.) Known distribution and migration area for Pygmy Blue Whales to the north of the area. Whale Shark foraging area along the 200 m isobath.

Table 1 Breeding periods (b) for key seabirds whose foraging areas are adjacent to or overlapping to the AC17-5 Release Area. Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec Greater b b b b b b b b Frigatebi rd Lesser b b b b b b b b b b Frigatebi rd Red-footed b b b b b Booby Wedge- b b b b b b b b b tailed Shearwa ter White-tailed b b b b b b Tropicbir d

The Atlas of Living Australia (www.ala.org.au) and the North-West Atlas (www.northwestatlas.org) provide further information and visualisations concerning animals and plants recorded from the release area, including Threatened or Listed species.

9AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 9 Heritage No shipwrecks are listed in the area.

References and Information Resources National Conservation Values Atlas http://www.environment.gov.au/webgis- framework/apps/ncva/ncva.jsf Atlas of Living Australia http://www.ala.org.au/ Ashmore Reef Commonwealth Marine Reserve https://www.environment.gov.au/topics/marine/marine-reserves/north-west/ashmore Cartier Island Commonwealth Marine Reserve https://www.environment.gov.au/topics/marine/marine-reserves/north-west/cartier Kimberley Commonwealth Marine Reserve https://www.environment.gov.au/topics/marine/marine-reserves/north-west/kimberley Commonwealth Fisheries http://www.afma.gov.au/fisheries/ Western Australian Fisheries http://www.fish.wa.gov.au/Fishing-and- Aquaculture/Commercial-Fishing/ Shipwrecks http://www.environment.gov.au/heritage/historic-shipwrecks/australian-national- shipwreck-database

Geoscience Australia products

Regional geology and seismic

A regional assessment of CO2 storage potential in the Browse Basin: Results of a study undertaken as part of the National CO2 Infrastructure Plan. Geoscience Australia Record 2016/17 by Rollet et al (2016a). http://dx.doi.org/10.11636/Record.2016.017 Petroleum geology inventory of Australia’s offshore frontier basins. Geoscience Australia Record 2014/09 by Totterdell et al (2014). http://dx.doi.org/10.11636/Record.2014.009 Browse Basin Well Composites. Dataset by Ryan et al, 2005. Basement and Crustal Structure of the Bonaparte - Browse Basins. Conference abstract by Goncharov et al, 2003. Interpreted Horizons and Faults for Seismic Survey 119. Browse Basin. Data package by Kennard et al, 2001. Interpreted Horizons and Faults for Seismic Survey 130. Browse Basin. Data package by Kennard et al, 2001. Line Drawings of AGSO – Geoscience Australia’s Regional Seismic Profiles, Offshore Northern and Northwestern Australia. Geoscience Australia Record 2001/36 by Colwell and Kennard 2001. Browse Basin High Resolution Seismic Study – North West Shelf, Australia – Interpretation Report. Australian Geological Survey Organisation Record 1997/38 by Blevin et al, 1997.

10AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 10 Stratigraphy Browse Basin Biozonation and Biostratigraphy Chart 32. Chart by Kelman et al, 2016. Seven Cretaceous low-order depositional sequences from the Browse Basin, North West Shelf, Australia: a framework for CO2 storage studies. Conference abstract by Abbott et al (2015). Evolution of early Campanian to Maastrichtian supersequences in the Caswell Sub-basin - implications for CO2 storage and hydrocarbon entrapment. Conference abstract by Lech et al (2015).

Petroleum systems and accumulations New insights into the petroleum prospectivity of the Browse Basin: results of a multi- disciplinary study. Extended APPEA 2016 conference abstract by Rollet et al., 2016. http://www.publish.csiro.au/AJ/AJ15034

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 by Howard et al, 2016). Geochemical 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. Abstract by Edwards et al (2015). The source of oil and gas accumulations in the Browse Basin, North West Shelf of Australia: a geochemical assessment. AAPG International Conference and Exhibition, 13–16 September 2015, Melbourne, Australia, Abstract by Grosjean et al., 2015. Australian Petroleum Accumulations Report 7 Browse Basin: Western Australia and Territory of Ashmore and Cartier Islands Adjacent Area, 2nd edition, Geoscience Australia Record 2015/10 by Le Poidevin et al., 2015. Redefining 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 by Edwards et al, 2014. Hydrocarbon Generation and Expulsion from Early Cretaceous Source Rocks in the Browse Basin, North West Shelf, Australia: A Small Angle Neutron Scattering and Pyrolysis Study. Geoscience Australia Record 2007/04 by Radlinski et al, 2006. Geoscience Australia Survey 267, Post Survey Report: Testing Natural Hydrocarbon Seepage Detection Tools on the Yampi Shelf, Northwestern Australia. Geoscience Australia Record 2005/15 by Jones et al, 2005. The Oils of Western Australia II. 2005. Publication by Edwards and Zumberge 2005. Source Rock Time Slice Maps: Offshore Northwest Australia, 2004. Dataset by West et al, 2004. Subsidence and Thermal History Modelling: New Insights into Hydrocarbon Expulsion from Multiple Petroleum Systems in the Browse Basin. Conference abstract by Kennard et al, 2003. Characterisation of Natural Gases from West Australian Basins. Publication by Boreham et al, 2000.

11AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 11 Hydrocarbon Migration and Seepage in the Timor Sea and Browse Basin, North West Shelf, Australia: An Integrated SAR, Geological and Geochemical Study. Geoscience Australia Record 2001/11 by O’Brien et al, 2000. Browse Basin Organic Geochemistry Study, North West Shelf, Australia. Australian Geological Survey Organisation Record 1997/57 by Boreham et al, 1998.

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12AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 12 References ABBOTT, S., CAUST, D., ROLLET, N., LECH, M., ROMEYN, R., ROMINE, K., KHIDER, K. AND BLEVIN, J., 2015—Seven 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. Abstract. http://www.searchanddiscovery.com/pdfz/documents/2016/51224abbott/ndx_abbott.pdf.htm l (last accessed February 3, 2017). ADAMO, N. D., FANDRY, C., BUCHAN, S. AND DOMINGUES, C., 2009—Northern sources of the Leeuwin Current and the "Holloway Current" on the North West Shelf. Journal of the Royal Society of Western Australia, 92, 53–66. AGSO, 2001—Line drawings of AGSO – Geoscience Australia’s Regional Seismic Profiles, Offshore Northern and Northwestern Australia. Record, 2001/36, Australian Geological Survey Organisation, Canberra. AGSO AND GEOTECH, 2000—[Web page] Characterisation of Natural Gases from West Australian Basins. Browse Basin Module. http://www.ga.gov.au/metadata- gateway/metadata/record/gcat_33569 (last accessed 10 February, 2017). AGSO BROWSE BASIN PROJECT TEAM, 1997—Browse Basin High Resolution Study, Interpretation Report, North West Shelf, Australia. Australian Geological Survey Organisation, Record 1997/38. https://d28rz98at9flks.cloudfront.net/23689/Rec1997_038.pdf (last accessed 10 February, 2017). BELDE, J., BACK, S. AND REUNING, L., 2014—Three-dimensional seismic analysis of sediment-waves and related geomorphological features on a carbonate shelf exposed to large amplitude internal waves, Browse Basin region, Australia. Sedimentology, 62(1), 87– 109 . BENSON, J.M., BREALEY, S.J., LUXTON, C.W., WALSHE, P.F. AND TUPPER, N.P., 2004—Late Cretaceous ponded turbidite systems: a new stratigraphic play fairway in the Browse Basin. The APPEA Journal, 44(1), 269–285. BLEVIN, J.E., BOREHAM, C.J., SUMMONS, R.E., STRUCKMEYER, H.I.M. AND LOUTIT, T.S., 1998a—An effective Lower Cretaceous petroleum system on the North West Shelf: evidence from the Browse Basin. In: Purcell, P.G. and R.R. (eds), 1998, The Sedimentary Basins of Western Australia 2: Proceedings of the Petroleum Exploration Society of Australia Symposium, Perth, WA, 1998, 397–420. BLEVIN, J.E., STRUCKMEYER, H.I.M., CATHRO, D.L., TOTTERDELL, J.M., BOREHAM, C.J., ROMINE, K.K., LOUTIT, T.S. AND SAYERS, J., 1998b—Tectonostratigraphic framework and petroleum systems of the Browse Basin, North West Shelf. In: Purcell, P.G. and R.R. (eds), 1998, The Sedimentary Basins of Western Australia 2: Proceedings of the Petroleum Exploration Society of Australia Symposium, Perth, WA, 1998, 369–395. BRINCAT, M.P., LISK, M., KENNARD, J.M., BAILEY, W.R. AND EADINGTON, P.J., 2004 —Evaluating the oil potential of the Caswell Sub-basin; insights from fluid inclusion studies. Special Publication - Northern Territory Geological Survey, 437–455.

13AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 13 CLARKE, R.H., 2010 —The status of seabirds and shorebirds at Ashmore Reef and Cartier and Browse Islands: Monitoring program for the Montara Well Release - Pre-impact assessment and first post-impact field survey. prepared for: PTTEP Australasia and the Department of the Environment, Water, Heritage and the Arts, Australia. COLLINS, L.B., 2011—Geological setting, marine geomorphology, sediments and Oceanic Shoals growth history of the Kimberley region. Journal of the Royal Society of Western Australia, 94, 89-105. COLLINS, L.B., 2014—Carbonate shelf sediments of the western continental margin of Australia. In: CHIOCCI, F. L. & CHIVAS, A. R. (eds.) Continental Shelves of the World: Their evolution during the last Glacio-eustatic cycle. London: Geological Society, London. COLLINS, L.B. AND TESTA, V., 2010—Quaternary development of resilient reefs on the subsiding Kimberley continental margin, northwest Australia. Brazilian Journal of Oceanography, 58, 67-77. CONDIE, S. A. AND ANDREWARTHA, J.R., 2008—Circulation and connectivity on the Australian North west shelf. Continental Shelf Research, 28, 1724-1739. EDWARDS, D.S., GROSJEAN, E., KUSKE, T., LE POIDEVIN, S., CHEN, J., HONG, Z., BOREHAM, C., ROLLET, N. AND ZUMBERGE, J., 2014—Redefining the petroleum systems of the Browse Basin. In McKirdy, D. M. and Löhr, S. (eds) Life, Environments and Resources. AOGC2014: the 18th Australian Organic Geochemistry Conference, 30 November – 2 December 2014, Adelaide. Program and Abstracts p40. GIBBARD, P.L., HEAD, M.J., WALKER, M.J.C. AND THE SUBCOMMISSION ON QUATERNARY STRATIGRAPHY, 2009—Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science, 25, 96-102. GROSJEAN, E., EDWARDS, D.S., KUSKE, T., HALL, L., ROLLET, N. AND ZUMBERGE, J., 2015—The source of oil and gas accumulations in the Browse Basin, North West Shelf of Australia: a geochemical assessment. AAPG International Conference and Exhibition, 13–16 September 2015, Melbourne, Australia. Abstract. http://www.searchanddiscovery.com/pdfz/documents/2016/10827grosjean/ndx_grosjean.pd f.html (last accessed 20 February, 2017). HARRIS, P., HEAP, A., PASSLOW, V., SBAFFI, L., FELLOWS, M., PORTER-SMITH, R., BUCHANAN, C. AND DANIELL, J., 2003—Geomorphic features of the continental margin of Australia. Record 2003/30. Geoscience Australia, Canberra. http://www.ga.gov.au/metadata-gateway/metadata/record/61007 (last accessed 10 February, 2017). HEAD, M.J., GIBBARD, P. AND SALVADOR, A., 2008—The Quaternary: its character and definition. Episodes, 31, 234-238. HEAP, A.D. AND HARRIS, P.T., 2008—Geomorphology of the Australian margin and adjacent seafloor. Australian Journal of Earth Sciences, 55, 555-585. HOCKING, R.M., MORY, A.J. AND WILLIAMS, I.R., 1994—An atlas of Neoproterozoic and Phanerozoic basins of Western Australia. In: Purcell, P.G. and R.R. (eds), The Sedimentary Basins of Western Australia: Proceedings of Petroleum Exploration Society of Australia Symposium, Perth, 1994, 21–43. HOLLOWAY, P.E., 1983—Tides on the Australian North-west shelf. Australian Journal of Marine and Freshwater Research, 34, 213-230.

14AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 14 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. AND TRAFFORD, J.,—A 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. Record 2016/05. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/Record.2016.005 (last accessed 6 February, 2017). JAMES, N.P., BONE, Y., KYSER, T.K., DIX, G.R. AND COLLINS, L.B., 2004—The importance of changing oceanography in controlling late Quaternary carbonate sedimentation on a high-energy, tropical, oceanic ramp: north-western Australia. Sedimentology, 51, 1179-1205. KEALL, J. AND SMITH, P., 2004—The Argus-1 discovery, Browse Basin. In: Ellis, G.K., Baillie, P.W. and Munson, T.J. (eds), Timor Sea Petroleum Geoscience. Proceedings of the Timor Sea Symposium, Darwin, 19–20 June 2003. Northern Territory Geological Survey, Special Publication, 1, 37–52. KELMAN, A., KHIDER, K., ROLLET, N., ABBOTT, S., GROSJEAN, E. AND LECH, M., 2016—[Web page] Browse Basin Biozonation and Stratigraphy, Chart 32, Geoscience Australia. https://d28rz98at9flks.cloudfront.net/76687/Chart_32_Browse_Basin_2016.pdf (last accessed 6 February, 2017). KENNARD, J.M., DEIGHTON, I., RYAN, D., EDWARDS, D.S. AND BOREHAM, C.J., 2004 —Subsidence and thermal history modelling: new insights into hydrocarbon expulsion from multiple petroleum systems in the Browse Basin. In: Ellis, G.K., Baillie, P.W. and Munson, T.J. (eds), Timor Sea Petroleum Geoscience. Proceedings of the Timor Sea Symposium, Darwin, 19–20 June 2003. Northern Territory Geological Survey, Special Publication 1, 411–435. KUHNT, W., BLUMEL, M., BOCH, R., DEWI, K.T., DA COSTA MONTEIRO, F., DURKOP, A., HANEBUTH, T., HEIDEMANN, U., HOLBOURNE, A., JIAN, Z., VAN DER KAARS, S., KAWAMURA, H., KAWOHL, H., NURNBERG, D., OBDYKE, B., PETERSEN, A., REGENBERG, M., ROSENTHAL, Y., RUHLEMANN, C., SADEKOV, A., SALOMON, B., TIAN, J., XU, J. AND ZURAIDA, R., 2006—Cruise Report SONNE-185 "Variability of the Indonesian Throughflow and Australasian Climate History of the Last 150 000 years (VITAL)". Kiel, Germany: Ins fur Geowiss., Christian-Albrechts Univ Zu Kiel. KUHNT, W., HOLBOURN, A., HALL, R., ZUVELA, M. AND KASE, R., 2004—Neogene history of the Indonesian Throughflow. In: Clift, P., Kuhnt, W., Wang, P. and Hayes, D. (eds.) Continent-Ocean interactions Within East Asian Marginal Seas. American Geophysical Union. LE POIDEVIN, S.R., KUSKE, T.J., EDWARDS, D.S. AND TEMPLE, P.R., 2015—Australian Petroleum Accumulations Report 7 Browse Basin: Western Australia and Territory of Ashmore and Cartier Islands Adjacent Area, 2nd edition, Record 2015/10. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/Record.2015.010 (last accessed 6 February, 2017). LISIECKI, L.E. AND RAYMO, M.E., 2005—A Pliocene-Pleistocene stack of 57 globally distributed benthic D18O records. Paleoceanography, 20, 1-17.

15AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 15 LONGLEY, I.M., BUESSENSCHUETT, C., CLYDSDALE, L., CUBITT, C.J., DAVIS, R.C., JOHNSON, M.K., MARSHALL, N.M., MURRAY, A.P., SOMERVILLE, R., SPRY, T.B. AND THOMPSON, N.B., 2002—The North West Shelf of Australia – a Woodside perspective. In: Keep, M. and Moss, S.J. (eds), 2002, The Sedimentary Basins of Western Australia 3: Proceedings of the Petroleum Exploration Society of Australia Symposium, Perth, WA, 2002, 27–88. MCKINNON, A. D., DUGGAN, S., HOLLIDAY, D. AND BRINKMAN, R., 2015—Plankton community structure and connectivity in the Kimberley-Browse region of NW Australia. Estuarine, Coastal and Shelf Science, 153, 156-167. NATIONAL CONSERVATION VALUES ATLAS, 2016—[Web page] Explore the Atlas of Living Australia http://www.ala.org.au/ (last accessed 6 February, 2017). NICHOLSON, C., ROMEYN, R., LECH, M., ABBOTT, S. T., BERNARDEL, G., CARROLL, A., CAUST, D., GROSJEAN, E., HACKNEY, R., HOWARD, F., MELROSE, R., NICHOL, S., RADKE, L., ROLLET, N., SIWABESSY, J. & TRAFFORD, J. 2015—Browse Basin 2014 Marine Survey: Investigating containment for potential Late Cretaceous CO2 storage plays. AAPG 2015. Melbourne, Australia: AAPG. http://www.searchanddiscovery.com/pdfz/documents/2016/80511nicholson/ndx_nicholson. pdf.html (last accessed 11 February, 2017). OGG, J.G., OGG, G.M., AND GRADSTEIN, F.M., 2016—A Concise Geologic Time Scale: 2016. Elsevier BV, 250 pp. PICARD, K., NICHOL, S. L., HASHIMOTO, R., CARROLL, A., BERNARDEL, G., JONES, L.E.A., SIWABESSY, P.J.W., RADKE, L.C., NICHOLAS, W.A., CAREY, M.C., STOWAR, M., HOWARD, F.J.F., TRAN, M. AND POTTER, A., 2014—Seabed environments and shallow geology of the Leveque Shelf, Browse Basin, Western Australia: Ga0340/SOL5754 - Post-survey report. Record 2014/10. Geoscience Australia, Canberra. http://www.ga.gov.au/metadata-gateway/metadata/record/78749 last accessed 11 February, 2017). PRYER, l., BLEVIN, J., NELSON, G., SANCHEZ, G., LEE, J.-D., CATHRO, D., GRAHAM, R. AND HORN, B., 2014—Structural architecture and basin evaluation of the North West Shelf. The APPEA Journal 54 (extended abstract). RADLINSKI, A.P., KENNARD, J.M., EDWARDS, D.S., HINDE, A.L. AND DAVENPORT, R., 2004—Hydrocarbon generation and expulsion from Early Cretaceous source rocks in the Browse Basin, North West Shelf, Australia: a small angle neutron scattering study. The APPEA Journal, 44(1), 151–180. RAYSON, M.D., IVEY, G.N., JONES, N.L., MEULENERS, M.J. AND WAKE, G.W., 2011— Internal tide dynamics in a topographically complex region: Browse Basin, Australian North West Shelf. Journal of Geophysical Research, 116, 17 pp. ROLLET, N., LOGAN, G. A., KENNARD, J. M., O'BRIEN, P. E., JONES, A. T. AND SEXTON, M., 2006—Characterisation and corrrelation of active hydrocarbon seepage using geophysical data sets: an example from the tropical carbonate Yampi Shelf, northwest Australia. Marine and Petroleum Geology, 23, 145-164. ROLLET, N., ABBOTT, S., LECH, M.E., ROMEYN, R., GROSJEAN, E., EDWARDS, D., TOTTERDELL, J., NICHOLSON, C., KHIDER, K., NGUYEN, D., BERNARDEL, G., TENTHOREY, E., ORLOV, C. AND WANG, L., 2016a—A regional assessment of CO2 storage potential in the Browse Basin: Results of a study undertaken as part of the National CO2 Infrastructure Plan. Record 2016/17. Geoscience Australia, Canberra. http://dx.doi.org/10.11636/Record.2016.017 (last accessed 6 February, 2017).

16AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 16 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. AND MCLENNAN, S., 2016b—New insights into the petroleum prospectivity of the Browse Basin: results of a multi-disciplinary study. APPEA Journal, Journal, 56 (1), 483- 494. http://www.publish.csiro.au/AJ/AJ15034 (last accessed 6 February, 2017). STEPHENSON, A.E. AND CADMAN, S.J., 1994—Browse Basin, Northwest Australia: the evolution, palaeogeography and petroleum potential of a passive continental margin. Palaeogeography, Palaeoclimatology, Palaeoecology, 111, 337-366. STRUCKMEYER, H.I.M., BLEVIN, J.E., SAYERS, J., TOTTERDELL, J.M., BAXTER, K. AND CATHRO, D.L., 1998—Structural evolution of the Browse Basin, North West Shelf: new concepts from deep-seismic data. In: Purcell, P.G. and R.R. (eds), 1998, The Sedimentary Basins of Western Australia 2: Proceedings of the Petroleum Exploration Society of Australia Symposium, Perth, WA, 1998, 345–367. SYMONDS, P.A., COLLINS, C.D.N. AND BRADSHAW, J., 1994—Deep structure of the Browse Basin: implications for basin development and petroleum exploration. In: Purcell, P.G. and R.R. (eds), The Sedimentary Basins of Western Australia: Proceedings of Petroleum Exploration Society of Australia Symposium, Perth, 1994, 315–331. TOVAGLIERI, F. AND GEORGE, A.D., 2014—Stratigraphic architecture of an Early–Middle Jurassic tidally influenced deltaic system (Plover Formation), Browse Basin, Australian North West Shelf. Marine and Petroleum Geology, 49, 59–83. TOVAGLIERI, F., GEORGE, A.D., JONES, T. AND ZWINGMANN, H., 2013—Depositional and volcanic history of the Early to Middle Jurassic deltaic reservoirs in Calliance and Brecknock fields (Plover Formation), Browse Basin, North West Shelf, Australia. West Australian Basins Symposium, Perth, WA, 18–21 August, 2013. VOLK, H., BRINCAT, M.P., GEORGE, S.C., KENNARD, J. M., EDWARDS, D.S., BOREHAM, C.J., AHMED, M. AND LISK, M., 2005—Clues to fill histories of gas fields in the Caswell Sub-basin; evidence from the distribution and geochemistry of palaeo-oils. The APPEA Journal, 45(1), 679. WILLIS, I., 1988—Results of exploration, Browse Basin, North West Shelf, Western Australia. In: Purcell, P.G. and R.R. (eds), The North West Shelf, Australia: Proceedings of Petroleum Exploration Society of Australia Symposium, Perth, 1988, 259–272. WILSON, B., 2013—The biogeography of the Australian North West Shelf: environmental change and life's response, Elsevier.

Figure captions Figure 1. Structural elements of the Caswell Sub-basin in the vicinity of Release Area W17-3 and Release Area AC17-5, showing petroleum fields, key wells, and the 2017 release areas. Figure 2. Stratigraphy and hydrocarbon shows in the Caswell Sub-basin and Yampi Shelf based on the Browse Basin Biozonation and Stratigraphy Chart (Kelman et al, 2016). Geologic Time Scale after Ogg et al (2016). Figure 3. Interpreted seismic dip line across the combined release area (See Figure 1 for location). Figure 4. Buccaneer 1 well composite (see Figure 1 for location).

17AUSTRALIA 2017 Offshore Petroleum Exploration Acreage Release 17 Figure 5. Schematic cross-sections (not to scale) depicting hydrocarbon play types in the Caswell Sub-basin within a) sequence stratigraphic, and b) lithostratigraphic context. Figure 6. Seismic and well data in the vicinity of the combined release area in the northeastern Caswell Sub-basin, Browse Basin.

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