Updated: 14th July 2005

Australian petroleum exploration and development activity report

1 October to 31 December 2004

To view the full report, including tables and figures you can download the Petroleum Industry Statistics Report for 4^th Quarter 2004 in PDF format.[PDF_500KB]

Highlights

Petroleum discoveries continued in the December quarter. Offshore, two oil discoveries were made at Altostratos in the Carnarvon Basin and at Katrandra in the Bonaparte Basin. Gas discoveries were made at Moby, Martha and Trefoil in the Gippsland, Otway and Bass Basins respectively. Onshore, three oil, one oil and gas and six gas discoveries were made all in the Cooper and Eromanga Basins of South Australia and Queensland.

During 2004 there were a total of ten Offshore discoveries, six in the Carnarvon Basin (4 oil, 1 oil and gas and 1 gas), one in the Gippsland Basin (gas), one in the Otway Basin (gas), one in the Bass Basin (gas) and one in the Bonaparte Basin (oil) - See Table 4 Onshore there were a total of 28 discoveries of which 21 were in the Cooper and Eromanga Basins (14 gas, 1 oil and gas, 6 oil), one in the Gippsland Basin (gas), one in the Surat Basin (oil) and five in the Perth Basin (1 oil, 4 gas).

Offshore exploration drilling in 2004 accounted for 50 wells drilled which is below the average number drilled in the last ten years and five wells less than the 55 wells drilled in 2003. Onshore exploration drilling in 2004 accounted for 86 wells drilled which is a considerable improvement over the 36 wells drilled in 2003 which was a very low level of drilling.

Overall seismic activity both 2D and 3D in 2004 is slightly below that acquired in 2003. Both the Onshore and Offshore seismic acquisitions failed to reach 2003 levels.

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Drilling activity

Exploration drilling for the December quarter 2004, totalled 39 wells, 13 more than drilled during the same period in 2003 and eight more than the 31 wells drilled in the previous quarter. Offshore exploration wells drilled during the December quarter 2004 totalled 15 which is six more than in the December quarter 2003 and four more than in the previous quarter. Four of these wells were drilled in the Carnarvon Basin, three each in the Otway and Gippsland basins, two in the Bonaparte Basin and one each in the Bass, Browse and Perth Basins. Onshore exploration wells in the December quarter 2004 totalled 24 which is four more than the previous quarter and seven more than the December quarter 2003. Sixteen of these wells were drilled in the Cooper/Eromanga Basin, four in the Perth Basin, Three in the Surat Basin and one in the Gippsland Basin. Development drilling activity for the December quarter 2004 of 24 wells is four less than the previous quarter (28) and is the same as the December quarter 2003. Offshore, the number of development wells drilled during the December quarter 2004 (11) is three less than the previous quarter and two more than the same quarter last year. These wells were drilled in the Carnarvon (7), Bonaparte (3) and Gippsland (1) Basins. Onshore, development wells drilled in the December quarter (13) is two less than the same quarter last year and one less than the previous quarter. These wells were drilled in the Cooper/Eromanga (7), Surat (3), Amadeus Basin (2) and Bowen (1) Basins.

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Seismic survey activity

Offshore, there was a total of 11,540 km of 2D seismic for the December quarter 2004. This was 4528 km more then September quarter 2004 and 4904 km more than in the December quarter 2003. The surveys were undertaken in the Carnarvon, Bonaparte, Bremer, Otway and Perth Basins. There was no 3D seismic surveys acquired during the December quarter 2004. Onshore, a total of 400 km of 2D seismic were acquired during the December quarter 2004. This is 509 km less than in the previous quarter. These surveys were undertaken in the Cooper Basin of South Australia and Queensland. 3D seismic surveys were undertaken over 413 km² which is slightly less than the 428 km² in the previous quarter. These surveys were also carried out in the Cooper Basin.

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Rig activity

The number of active rigs during December 2004 was eighteen, four more than at the end of September 2004 (14) and one more than at the end of December 2003 (17). Rig activity during the quarter ranged from eighteen to twenty with eighteen rigs active at the end of the quarter. Offshore, the number of available rigs during the December quarter 2004 is up on the previous quarter, with ten available for July and August and eleven in September. The September quarter 2004 had only Seven available in July and August and six in September. Active rigs were drilling in the Bonaparte, Carnarvon, Bass, Browse, Otway and Gippsland Basins. Onshore, the number of active rigs during the quarter ended December 2004 varied between nine and twelve, which is the same as the same period last year. The total number of inactive rigs for the December quarter varied between six and eight.

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Success rates

The success rates shown in Table 7 are based on the number of petroleum discoveries and new-field wildcat wells drilled in Australia Onshore and Offshore from 1992 to 2004. No assumptions have been made about whether a 'discovery' has proved or will prove to be commercial. Geoscience Australia defines a discovery as a well from which a measurable amount of oil or gas has been recovered and also includes those discoveries inferred from well logs.