Exploration History

Browse Basin Exploration Overview

The first well drilled in the Browse Basin was Leveque 1 (1970), which was a stratigraphic test of the sedimentary succession on the Leveque Shelf. This was followed by the discovery of gas at Scott Reef 1 in 1971. The well intersected a thick sequence of gas-bearing reservoirs within Early-Middle Jurassic (Plover Formation) sandstones and sandy dolostones of Late Triassic-Jurassic age on the southern culmination of a faulted anticline located on the Buffon-Scott Reef-Brecknock Anticlinal Trend. Gas flows of 278000-515000 m3/day were recorded from drill stem tests (DSTs), and were accompanied by 49-54°API gravity condensate (Willis, 1988). Two appraisal wells (Scott Reef 2A in 1977 and North Scott Reef 1 in 1982) were drilled to further delineate the extent of the field (Bint, 1988). North Scott Reef 1 recorded a maximum gas flow rate of 1.275x106 m3/day from a DST (Willis, 1988). No net hydrocarbon pay was assigned to the Scott Reef 2A well.

In 1979, Brecknock 1 tested a broad anticlinal feature 40 km southwest of Scott Reef. The well penetrated 68.3 m of net gas sandstone in Early to Middle Jurassic sediments, of similar age to the reservoir section at Scott Reef (Bint, 1988).

Other significant discoveries during the early 1980s include Brewster 1A ST1 (1980), Caswell 2 ST2 (1983) and Echuca Shoals 1 (1983). Log interpretations from Brewster 1A ST1 delineated gas-bearing sandstones of Berriasian age. Caswell 2 ST2 encountered numerous minor oil shows and high gas readings within the Late Jurassic and Early Cretaceous sediments, and it recovered oil from a thin Late Cretaceous (Campanian) sandstone. Log interpretation of the Echuca Shoals 1 well indicated gas in two separate reservoirs of Late Jurassic (Tithonian) to Early Cretaceous (Berriasian) age (Willis, 1988).

Between 1984 and 1994 exploration was focussed largely on the northern Caswell Sub-basin (Gryphaea 1 (1987), Asterias 1 (1987), Discorbis 1 (1989) and Kalyptea 1 ST1 (1989)), and along the basin margin faults of the Leveque and Yampi shelves (Trochus 1 ST1 (1991), Arquebus 1 ST1 (1991), Sheherazade 1 (1993), Copernicus 1 ST1 (1993) and Yampi 2 (1994)). Many of the wells reported minor hydrocarbon shows from Late Jurassic or Early Cretaceous reservoirs (Maung et al, 1994). Evidence of the hydrocarbon potential of the basin was demonstrated by the Gwydion 1 oil and gas discovery, and the Cornea 1 oil discovery (1997), both located on the Yampi Shelf.

Gwydion 1 discovered three gas-bearing zones and one oil/gas-bearing zone in Barremian to Albian shallow marine sandstones draped over a prominent basement high (Spry and Ward, 1997). The Cornea 1, 1B and 2 wells encountered a 25 m gas column overlying an 18 m oil column in the base Albian reservoir sequence (Ingram et al, 2000), and was the first oil discovery in what was previously considered to be a gas-prone basin (Stein et al, 1998). In 1998, Adele 1 discovered oil and gas in Middle Jurassic (Plover Formation) sandstones, and Psepotus 1 (1998) and Caspar 1A (1998) discovered small gas accumulations within Early Cretaceous sandstones on the Leveque Shelf and Yampi Shelf, respectively.

Drilling in 2000 resulted in the discovery of several major gas accumulations in the Browse Basin, as well as the extension of previously recognised gas provinces. Brecknock South 1, located on the Scott Reef-Brecknock-trend some 19 km south of Brecknock 1, intersected a 134 m gross gas column in good quality reservoir sandstones of the Middle Jurassic Plover Formation (King, 2001). To the north, on the same structural trend, Argus 1 encountered a gas column in excess of 240 m in Oxfordian sandstones and volcanics (Keall and Smith, 2004). Significant gas discoveries were encountered in the central Caswell Sub-basin in 2000 with the drilling of Titanichthys 1, Gorgonichthys 1 and Dinichthys 1 on the Brewster structure.

Crux 1, drilled in 2000 in the northeastern part of the Browse Basin, encountered a 280 m gross gas column in the Late Triassic to Early Jurassic Nome Formation (Kaoru et al, 2004).

In 2001-2002, exploration of Early Cretaceous lowstand fans and 'ponded' turbidite oil targets within the Caswell Sub-basin was unsuccessful (Carbine 1, Firetail 1 and Marabou 1 ST1). In 2002-2003 Maginnis 1A ST2 tested the hydrocarbon potential of the deep-water Seringapatam Sub-basin, but no hydrocarbons were encountered.

Evaluation of the gas accumulations along the Buffon-Scott Reef-Brecknock Anticlinal Trend continued in 2005-2007 with the drilling of the extension/appraisal wells Torosa 1, 2, and 3, Brecknock 2 and 3, and Calliance 1 and 2.

Appraisal drilling in the Ichthys gas field was completed in 2003-2004 (Ichthys 1A, Ichthys 2A ST2, and Ichthys Deep 1). Here, gas is primarily reservoired within the Upper Vulcan Formation (Brewster Member) and within the Plover Formation. Gas was also encountered within Callovian sandstones (named as the Ichthys Formation), and in basal Oxfordian sandstones of the Lower Vulcan Formation (Ban and Pitt, 2006).

Drilling continued in this region in 2007 with the drilling of Prelude 1A, Dinichthys North 1 and Tocatta 1 wells. Drilling results are not available at the time of writing.

Nexus Energy Ltd (2007a) reported that the Fossetmaker 1 appraisal well, drilled on the Echuca Shoals structure 7 km east-northeast of Echuca Shoals 1 and reached a total depth of 3822 m in September 2007. Wireline logs indicate the well encountered a 10 m tight gas interval with a low net to gross at a depth just below the 70 m main gas column seen in the Echuca Shoals 1 well. Nexus reported that further studies will be required to assess the commercial implications of this result for the Echuca Shoals gas accumulation.

The appraisal of the Crux gas field continued in 2006-2007 with acquisition of a 3D seismic survey and the drilling of the Crux 2 and Crux 2 ST1 wells. Nexus Energy Ltd (2007b) reports that the Crux 2 well confirmed a gross gas column of 70 m with a net 26 m of good quality sandstones in the Jurassic aged Plover Formation. The well did not intersect the required minimum thickness of reservoir sands necessary to support the proposed liquids project gas injection rate and a decision was made to sidetrack the well

The Crux 2 ST1 sidetrack location encountered the same gas reservoir sandstones as encountered in Crux 1. By sidetracking the Crux 2 well to a more optimal location the company plans to utilise the cased large-bore well as the first of six wells required for the potential recycling project.

Shell Development (Australia) Pty Ltd drilled a further six exploration wells (Gigue 1, Bouree 1A, Rigaudon 1, Rondo 1, Trio 1 and Fortissimo 1) in petroleum exploration permit WA-371-P in 2007. Drilling results are not available at the time of writing.

In June 2007, Woodside Energy Ltd drilled the top hole sections of the Snarf 1 exploration well (petroleum exploration permit WA-275-P) and Torosa 4 appraisal well. It is currently planned that a rig will return to drill the bottom hole section of these wells later in the year (DoIR, 2007).

Well Control

Only two wells, Yampi 1 and Yampi 2 have been drilled in the Release areas. Browse Island 1 was drilled in the northern onshore part of Release Area W08-07 and a number of wells have been drilled in petroleum exploration permits adjacent to the Release areas. Many of these central Caswell Sub-basin wells targeted basin floor fans and 'ponded' turbidite stratigraphic traps.

Yampi 1 (1973)

Yampi 1, drilled on a well defined easterly trending, Permo-Triassic fault controlled anticline, was the first well to be drilled in the central Browse Basin. The well penetrated a sedimentary and volcanic sequence ranging in age from Recent to Early Permian. Numerous minor hydrocarbon shows were recorded during drilling but Formation Interval Tests carried out over the intervals with the best shows produced only water and mud. Traces of residual oil were extracted during core analysis of a core cut in the Montara Sands (Lower Vulcan Formation). The well was plugged and abandoned at a total depth of 4176 mRT in Early Permian aged sediments.

Yampi 2 (1994)

Yampi 2 was drilled on the Yampi structure, 900 m south-southeast of Yampi 1 well, to follow-up hydrocarbon shows reported in the Yampi 1 well. Significant hydrocarbon indications were observed during drilling of the Montara Sands (Lower Vulcan Formation) and a core was cut. No significant direct fluorescence was noted and only very slow crush cut fluorescence was observed in the core. Minor hydrocarbon shows were noted in the Plover Formation and an RFT only recovered mud and water. Log interpretation estimates high water saturation throughout both zones indicating the hydrocarbons are immobile. The well was plugged and abandoned at a total depth of 3318 mRT terminating in volcanics within the Lower Plover Formation.

Browse Island 1 (1986)

Browse Island 1 was drilled to determine the thickness and interval velocity of the surface reef associated with Browse Island. The well was drilled to assist identification of the pull-up effect of a deeper seismically defined structure beneath the island. The well was plugged and abandoned at a total depth of 405.5 mRT in carbonates.

Caswell 1 (1978)

Caswell 1 targeted Jurassic sandstones in a northeast-trending anticlinal feature, but bottomed in Early Cretaceous claystones at 4097 mKB due to drilling difficulties. The well encountered oil and gas shows within Albian sandstones in the interval 3606-3611 mKB, but four sidewall cores within this interval recovered claystone, siltstone and limestone. A sample of oil with an API gravity of 46° was extracted from one of these sidewall cores. RFT tests confirmed over-pressuring in the Cretaceous claystones, but provided little information on the occurrence of hydrocarbons.

Caswell 2 ST2 (1983)

Caswell 2 ST2 was drilled to follow-up the shows encountered in Caswell 1 and to test Late Jurassic and Early-Middle Jurassic sandstones in a drape anticline. The well discovered a thin oil accumulation within Campanian silty sandstones at 3264.7-3268.7 mKB. An RFT fluid sample taken at 3265.5 mKB in the second sidetrack well recovered 0.8 l of oil with an API gravity of 47° and 21.2 cf gas. No significant hydrocarbons were recorded in the overlying clean Campanian sandstone between 3009 and 3215 mKB, but numerous minor oil shows and high gas readings were encountered below 3680 mKB in claystones and low porosity sandstones in the Early Cretaceous and Upper-Middle Jurassic section. Caswell 2 ST2 terminated in Middle Jurassic sediments of the Plover Formation at 5000 mKB.

Walkley 1 (1993)

Walkley 1 targeted two submarine fan sandstones of Campanian (primary objective) and Barremian age within a 4-way dip mounded structural/stratigraphic play. Caswell 1 and 2 ST2 were previously drilled on the flank of the same structure. The well intersected Campanian reservoir sands in the Puffin Formation (2899-3062 mKB) which had no significant hydrocarbon shows, and failed to encounter the deeper prognosed Barremian sands. High gas readings were recorded in the Aptian radiolarite and peaked within Barremian claystones (3732 mKB to total depth at 3950 mKB).

Marabou 1 ST1 (2001)

Marabou 1 ST1 was drilled in the central part of the Caswell Sub-basin. Log interpretation suggested a 22 m gas accumulation within a small four-way dip closure (Benson et al, 2004). The probable occurrence of trapped hydrocarbons at Marabou 1 ST1 indicates that the vertical migration from the Early Cretaceous (Echuca Shoals Formation) source rocks is probably effective, but up-dip seal is lacking at this location (Benson et al, 2004).

Firetail 1 (2002)

Firetail 1 targeted Campanian turbidite sandstones of the Puffin Formation in a 4-way dip closure, similar to that tested at Caswell 1 and 2 ST2, Walkley 1 and Marabou 1 ST1 (Woodside Petroleum, 2002). The well was plugged and abandoned as a dry hole (Benson et al, 2004).

Two wells, Gwydion 1 (1995) and Caspar 1A (1998) were drilled some 30 km east of Release Area W08-7.

Gwydion 1 (1995)

Gwydion 1 tested a series of stacked Early Cretaceous seismic amplitude anomalies draped over a prominent basement high. Three separate gas reservoirs, ranging in thickness from 4-6 m, were intersected in Albian to Aptian glauconitic sandstones. An RFT program consisting of pretests and samples confirmed the presence of gas in each of these reservoirs. A deeper gas-oil reservoir was also encountered. This lowermost hydrocarbon zone is Hauterivian-Barremian in age and consists of 9.5 m net oil-filled sandstone (30º API oil) overlain by 12.6 m of net gas-filled glauconitic sand (Spry and Ward, 1997). The well has validated an Early Cretaceous drape (over basement) play on the Yampi Shelf that is dependent on long distance oil migration from the Browse Basin depocentre (this play was subsequently extended by the Cornea discovery wells). Oil recovered at both Gwydion1 and the Cornea field indicate that the late gas charge in the Browse Basin has not excluded oil from all traps.

Caspar 1A (1998)

Caspar 1A was drilled to test a small drape closure within sandstones of the Echuca Shoals Formation, which overlie basement. Logs and MDT sampling indicate a 5 m gas column was discovered in low porosity sandstones underlain by traces of residual biodegraded oil, believed to represent an earlier hydrocarbon charge. No hydrocarbons were encountered in other potential reservoir facies of the Echuca Shoals Formation in the well, indicating that migration across the Yampi Shelf is potentially complex and possibly restricted to specific carrier beds.

The giant Ichthys gas accumulation is located some 30 km north and west of Release areas W08-7 and W08-8 (Inpex, 2006). Gas is primarily reservoired within the Upper Vulcan Formation (Brewster Member) and within the Plover Formation. Gas was encountered within Callovian sandstones (named as the Ichthys Formation), and in basal Oxfordian sandstones of the Lower Vulcan Formation (Ban and Pitt, 2006).

Key Wells Listing - Release areas W08-7, W08-8, W08-9 and W08-10, Caswell Sub-basin

Well Operator Total Depth (m) Year$ Data Avail* Basic Avail Interp Avail Source#
Adele 1 Shell Development (Australia) Ltd 4822 1998 A - - -
Bouree 1 Shell Development (Australia) Pty Ltd 2258 2007 C 11/05/2009 11/05/2012 WAPIMS
Bouree 1A Shell Company of Australia Ltd 2258 2007 C 11/06/2009 10/06/2012 RRD
Brewster 1 Woodside Petroleum Development Pty Ltd 633 1980 A - - -
Brewster 1A Woodside Petroleum Development Pty Ltd 4464 1980 A - - -
Brewster 1A ST1 Woodside Petroleum Development Pty Ltd 4703 1980 A - - -
Browse Island 1 Santos Ltd 405.5 1986 A - - -
Buccaneer 1 Shell Development (Australia) Pty Ltd 3574 1990 A - - -
Carbine 1 Santos Ltd 1561 2001 A - - -
Caspar 1 BHP Petroleum Pty Ltd 392 1998 A - - -
Caspar 1A BHP Petroleum Pty Ltd 1099 1998 A - - -
Caswell 1 Woodside Petroleum Development Pty Ltd 4097 1978 A - - -
Caswell 2 Woodside Offshore Petroleum Pty Ltd 3396 1983 A - - -
Caswell 2 ST1 Woodside Offshore Petroleum Pty Ltd 4900 1983 A - - -
Caswell 2 ST2 Woodside Offshore Petroleum Pty Ltd 5000 1983 A - - -
Cornea 1 Shell Development (Australia) Pty Ltd 831 1997 A - - -
Cornea 1A Shell Development (Australia) Ltd 656 1997 A - - -
Cornea 1B Shell Development (Australia) Ltd 980 1997 A - - -
Dinichthys 1 Inpex Browse Ltd 4562 2000 A - - -
Dinichthys North 1 Inpex Browse Ltd 4926 2007 C 9/08/2009 9/08/2012 WAPIMS
Echuca Shoals 1 Woodside Offshore Petroleum Pty Ltd 4365 1984 A - - -
Firetail 1 Woodside Energy Ltd 3355 2002 A - - -
Focus 1 Shell Development (Australia) Ltd 801 1998 A - - -
Fossetmaker 1 Shell Development (Australia) Pty Ltd 3822 2007 C 8/10/2009 7/10/2012 RRD
Gigue 1 Shell Development (Australia) Pty Ltd 1881 2007 C 16/04/2009 16/04/2012 WAPIMS
Gorgonichthys 1 Inpex Browse Ltd 4767 2000 A - - -
Gwydion 1 BHP Petroleum Pty Ltd 876 1995 A - - -
Heywood 1 BOC of Australia Ltd 4572 1974 A - - -
Ichthys 1 Inpex Browse Ltd 2436 2003 B - 9/08/2008 RRD
Ichthys 1A Inpex Browse Ltd 4826 2003 B - 7/11/2008 WAPIMS
Ichthys 2A Inpex Browse Ltd 1751 2004 B - 18/03/2009 RRD
Ichthys 2A ST1 Inpex Browse Ltd 4177 2004 B - 18/03/2009 RRD
Ichthys 2A ST2 Inpex Browse Ltd 4752 2004 B - 18/03/2009 RRD
Ichthys Deep 1 Inpex Browse Ltd 4956 2003 B - 27/12/2008 WAPIMS
Kaleidoscope 1 Coveyork Pty Ltd 4437 2001 A - - -
Marabou 1 Santos Ltd 2863 2002 A - - -
Marabou 1 ST1 Santos Ltd 3729 2002 A - - -
Prelude 1 Shell Development (Australia) Pty Ltd 1481 2006 C 8/01/2009 8/01/2012 RRD
Prelude 1A Shell Development (Australia) Pty Ltd 4361 2007 C 30/03/2009 30/03/2012 WAPIMS
Prudhoe 1 BOC of Australia Ltd 892 1974 A - - -
Prudhoe 1 ST1 BOC of Australia Ltd 3322 1974 A - - -
Rigaudon 1 Shell Company of Australia Ltd 2297 2007 C 7/07/2009 6/07/2012 RRD
Rob Roy 1 BOC of Australia Ltd 2286 1972 A - - -
Sparkle 1 Shell Development (Australia) Ltd 707 1998 A - - -
Titanichthys 1 Inpex Browse Ltd 4602 2000 A - - -
Tocatta 1 Shell Company of Australia Ltd 4623 2007 C 3/09/2009 2/09/2012 RRD
Walkley 1 Ampolex Ltd 3950 1993 A - - -
Yampi 1 BOC of Australia Ltd 4176 1973 A - - -
Yampi 2 BHP Petroleum Pty Ltd 3318 1994 A - - -

$Year is based on Rig-release date, * A = All data (Basic and Interpretive) are available, B = Basic data only available, C = Basic and Interpretive data are confidential. # RRD = Rig release date. Data is accurate at 16 January 2008.

Seismic Coverage

Release areas W08-7, W08-8, W08-9 and W08-10 have been covered by a broad grid of reconnaissance seismic lines with some finer detail in the vicinity of well locations and leads (Figure 8). The data is of varying vintage and quality - the 1970s data is of poor quality but the later data, acquired in the 1990s, is generally of fair to good quality.

To date, no 3D seismic surveys have been acquired over the Release areas; however, the North Browse TQ 3D seismic survey was acquired in 1998 (not shown in Figure 8) adjacent to the northern boundary of Release areas W08-9 and W08-10 and Phase 2 of this survey was acquired over the Ichthys gas accumulation.

Seismic Surveys - W08-7

Survey Name Client Line km's Year Processed Data Field Data Snip ID PIMS ID
Browse Basin Burmah Oil 2578 1972 Yes Yes 594 S6720063
Prudhoe-Hibernia Burmah Oil 2561 1972 Yes Yes 596 S6720085
Tessa-Troubadour BOCAL, Woodside & Other partners 5572 1975 Yes Yes 152 S0750001
Dampier-Broome Marine Seismic: Project 81D Woodside 2536 1981 Yes Yes 155 S6810045
Calliance Reef Doral Resources 1042 1982 Yes Yes 484 S6830027
Fantome Doral Resources 488 1985 Yes Yes 585 S6850012
Scobell Seahawk Oil 346 1985 Yes No 584 S6850003
BW87_34P BHP 1092 1987 Yes Yes 101 S6870009
BS91 Shell 619 1991 Yes Yes 25 S6910020
HY1 BHP 2771 1992 Yes Yes 107 S6920021
AGSO Marine Survey 119, Browse AGSO 4043 1993 Yes Yes 599 S6930071
Sarah Ampolex 1146 1993 Yes Yes 420 S6920030
AGSO Marine Survey 130, Browse Basin AGSO 3692 1994 Yes Yes 741 S6940031
HY93 BHP 513 1994 Yes Yes 128 S6930059
HY94 BHP 531 1994 Yes No 28 S6940025
AGSO Marine Survey 165, Yampi Tertiary Tie AGSO 2016 1995 Yes Yes 742 S6950038
Catherine Marine Seismic Ampolex 847 1995 Yes Yes 312 S6940016
HY95B BHP 2490 1995 Yes No 615 S6950029
AGSO Marine Survey 175, Browse Basin Regional Tie AGSO 5264 1996 Yes Yes 602 S6960034
HY97 BHPP 351 1997 Yes No 879 S6970024
IB98 Inpex Browse 4700 1998 Yes Yes 1564 S6980042

Data is accurate as at 17 December 2007.

Seismic Surveys - W08-8

Survey Name Client Line km's Year Processed Data Field Data Snip ID PIMS ID
Browse Basin Burmah Oil 2578 1972 Yes Yes 594 S6720063
Tessa-Troubadour BOCAL, Woodside & Other partners 5572 1975 Yes Yes 152 S0750001
Calliance Reef Doral Resources 1042 1982 Yes Yes 484 S6830027
Fantome Doral Resources 488 1985 Yes Yes 585 S6850012
Scobell Seahawk Oil 346 1985 Yes No 584 S6850003
Leveque Margin Halliburton Geophysical Services 2747 1986 Yes Yes 575 S6860020
BW87_34P BHP 1092 1987 Yes Yes 101 S6870009
A89M Enneidra Marine Seismic Ampolex 2582 1989 Yes Yes 311 S6890024
1991 MI Marine Seismic Ampolex 676 1991 Yes Yes 309 S6910028
HY1 BHP 2771 1992 Yes Yes 107 S6920021
AGSO Marine Survey 119, Browse AGSO 4043 1993 Yes Yes 599 S6930071
Sarah Ampolex 1146 1993 Yes Yes 420 S6920030
AGSO Marine Survey 130, Browse Basin AGSO 3692 1994 Yes Yes 741 S6940031
Catherine Marine Seismic Ampolex 847 1995 Yes Yes 312 S6940016
AGSO Marine Survey 175, Browse Basin Regional Tie AGSO 5264 1996 Yes Yes 602 S6960034
IB98 Inpex Browse 4700 1998 Yes Yes 1564 S6980042
Exeter Santos Ltd 1773 1999 Yes Yes 2424 S6990016

Data is accurate as at 17 December 2007.

Seismic Surveys - W08-9

Survey Name Client Line km's Year Processed Data Field Data Snip ID PIMS ID
Browse Basin Burmah Oil 2578 1972 Yes Yes 594 S6720063
Mermaid Cartier Burmah Oil 4326 1973 Yes Yes 609 S6730011/29
Churchill 1980 Marine Seismic not known 898 1980 Yes Yes 2486 S6800005
Calliance Reef Doral Resources 1042 1982 Yes Yes 484 S6830027
Fantome Doral Resources 488 1985 Yes Yes 585 S6850012
Leveque Margin Halliburton Geophysical Services 2747 1986 Yes Yes 575 S6860020
BW87_34P BHP 1092 1987 Yes Yes 101 S6870009
A89M Enneidra Marine Seismic Ampolex 2582 1989 Yes Yes 311 S6890024
1991 MI Marine Seismic Ampolex 676 1991 Yes Yes 309 S6910028
AGSO Marine Survey 119, Browse AGSO 4043 1993 Yes Yes 599 S6930071
Sarah Ampolex 1146 1993 Yes Yes 420 S6920030
AGSO Marine Survey 130, Browse Basin AGSO 3692 1994 Yes Yes 741 S6940031
Catherine Marine Seismic Ampolex 847 1995 Yes Yes 312 S6940016
AGSO Marine Survey 175, Browse Basin Regional Tie AGSO 5264 1996 Yes Yes 602 S6960034
IB98 Inpex Browse 4700 1998 Yes Yes 1564 S6980042
Exeter Santos Ltd 1773 1999 Yes Yes 2424 S6990016
Cathedral 2D Marine Seismic Survey Santos Ltd 639 2000 Yes Yes 2560 S6200023

Data is accurate as at 17 December 2007.

Seismic Surveys - W08-10

Survey Name Client Line km's Year Processed Data Field Data Snip ID PIMS ID
Browse Basin Seismic Burmah Oil 2578 1972 Yes Yes 594 S6720063
Mermaid Cartier Burmah Oil 4326 1973 Yes Yes 609 S6730011/29
Tessa-Troubadour Marine Seismic, Gravity & Magnetic BOCAL, Woodside & Other partners 5572 1975 Yes Yes 152 S0750001
Churchill 1980 Marine Seismic not known 898 1980 Yes Yes 2486 S6800005
Calliance Reef Doral Resources 1042 1982 Yes Yes 484 S6830027
Caswell-Echuca Marine Seismic Survey Woodside 610 1984 Yes Yes 858 S6840010/14
Leveque Margin Halliburton Geophysical Services 2747 1986 Yes Yes 575 S6860020
BW87_34P BHP 1092 1987 Yes Yes 101 S6870009
A89M Enneidra Marine Seismic Ampolex 2582 1989 Yes Yes 311 S6890024
1991 MI Marine Seismic Ampolex 676 1991 Yes Yes 309 S6910028
Eliza 1991 Ampolex 540 1991     313 S6910054
AGSO Marine Survey 119, Browse AGSO 4043 1993 Yes Yes 599 S6930071
AGSO Marine Survey 130, Browse Basin AGSO 3692 1994 Yes Yes 741 S6940031
AGSO Marine Survey 175, Browse Basin Regional Tie AGSO 5264 1996 Yes Yes 602 S6960034
Exeter Santos Ltd 1773 1999 Yes Yes 2424 S6990016
Griffin Santos Ltd 4020 1999 Yes Yes 2425 S6990013
Cathedral 2D Marine Seismic Survey Santos Ltd 639 2000 Yes Yes 2560 S6200023

Data is accurate as at 17 December 2007.