Gurdip Singh - Contributing Editor
Three FPSOs are being added to the four already operating off Northern Territory, says Moshtak Othman, petroleum resource manager at the Department of Primary Industry, Fisheries and Mines (DPIFM), Northern Territory, Australia.
Coogee Resources is commissioning an FPSO for the Swift/Swallow/Skua and Montara projects. Meanwhile, Nexus Energy has planned an FPSO for the Crux condensate extraction and recycling project for possible commissioning by 2010, Othman says. Separately, the FPSOModec Venture 1 has been assigned to a new development at Territory of Ashmore and Cartier Islands Adjacent Area.
The Principal Northern Territory PSL Adjacent Area includes over 0.5 million sq km (193,051 sq mi) of sea around the Territory coastline and the international borders of Australia. It comprises 17 exploration permits and four retention leases. This area, along with the Territory of Ashmore Cartier Islands Adjacent Area, is administered by the Northern Territory government on behalf of the Commonwealth.
Adding FPSOs
Coogee is expected to begin development drilling at the Swift/Swallow/Skua and Montara oil discoveries in 1Q 2009. It has installed a wellhead jacket, topsides, and pipelines, and the platform is being installed. Although one FPSO will host the tiebacks from these oil resources, Montara is a separate oil and gas pool under a separate production license.
Skua is an old oil field that produced 20.492 MMbbl until production was ceased on Feb. 27, 1997, by then-operator BHP. The FPSOSkua Venture was taken to Singapore for refurbishing and was renamed Modec Venture 1.
Modec Venture 1 did not return to Skua oil field because of the low oil price then, and Skua remained closed with proven recoverable oil known in that reservoir.
Now Coogee will redevelop Skua to produce the recoverable oil left after 1997. Swift/Swallow are newly discovered fields being developed.
Nexus’ appraisal well, Crux-3, has confirmed a thick condensate-rich gas column in AC/P23 Crux field, which was first discovered by Nippon Oil in 2000.
Drilled between Dec. 7, 2007, and Jan. 23, 2008, the well intersected 150 m (492 ft) of high quality net gas pay over a gross vertical gas column of 300 m (984 ft), and an additional 13 m (43 ft) of gas-charged sandstone. The follow-on Crux-4 well has intersected over 300 m (984 ft) of gas column above the gas/water contact.
Nexus, which acquired the field in 2006, estimates Crux contains a mean gas resource volume of over 2 tcf with a condensate/gas ratio (CGR) of approximately 35 bbl/MMcf of gas, giving a most likely recoverable condensate volume of 66.3 MMbbl.
Nexus, along with partner Osaka Gas, has started detailed engineering and design activities with first production scheduled for the second half of 2010. The $1-billion gas recycling project will produce through three to four wells and have three gas injection wells.
The plateau production rate is anticipated to be 32,500 b/d of condensate, says Moshtak.
Prior to the results at Crux-3 and Crux-4, Nexus declared condensate reserves between 54.9 and 78.3 MMbbl.
Nexus also is partner in a Shell joint venture which the company said at presstime was to drill Libra-1 in neighboring AC/P41 permit in late October. The well could have a significant impact on the future of Crux, as the successful outcome could increase Crux reserves and prove its extension into AC/P41.
The AC/P41 work program consists of three exploration wells, the acquisition of 3D seismic data, and other studies.
The likelihood of the Auriga prospect in AC/P23 permit would enable a larger Crux development to be considered.
Viking Field Development Solutions Pty Ltd. is to provide an FPSO with capacity to process and re-inject over 900 MMcf/d of gas with 650,000 bbl of condensate storage capacity.
Coogee Resources (Ashmore Cartier) Pty Ltd. took AC/P40 permit on March 1, 2007, with a work program comprising seismic acquisition, extensive exploration drilling of four wells, and other studies.Modec Venture 1 has been assigned to the new development.
Other ongoing projects
Woodside Energy Ltd. is further assessing the potential of Corallina field, which along with Laminaria, is experiencing declining oil production with a high water cut, now averaging over 80%. This is due to natural depletion.
A subsurface study was undertaken last year to better understand the oil accumulation in the Corallina field, which showed that there was likely to be incremental oil volumes in the eastern part of the field.
Two appraisal and development wells were to be drilled this year but a seismic survey has been inconclusive on the substructure of Corallina. Woodside is evaluating the results of the Corallina-4 well, which was drilled between Aug. 3-23, 2008, to further appraise the producing field.
Production from Laminaria/Corallina has peaked at over 180,000 b/d through the FPSONorthern Endeavour.
MEO Australia’s Heron-2 exploration well in NT/P68 encountered several drilling problems and high expense due to its depth and the high downhole temperature. Spudded on Oct. 12, 2007, Heron-2 encountered multiple gas columns in several formations, and tested 6 MMcf/d of gas flow from a secondary objective reservoir. The main reservoir was damaged by drilling problems and significant mud losses, and was not flow tested.
Meanwhile, the North West Shelf Venture’s Angel project has started production on Oct. 3, 2008.
The Angel project is a new addition to the North West Shelf Joint Venture (NWS) with production capacity of up to 800 MMcf/d of gas and up to 50,000 b/d of condensate. The project has a new platform and associated infrastructure, including a 50 km (31 mi) subsea pipeline tied back to the existing North Rankin A platform.
The Angel platform, approximately 115 km (71 mi) off Western Australia in about 80 m (262 feet) of water, is supplied by three subsea production wells. The additional gas volumes will underpin NWS’ five trains of LNG production. Its development began in December 2006.
