Australia: Octanex Completes Tamar Seismic Survey
Octanex N.L. announces that the Tamar 3D seismic survey, located within the WA-420-P permit, has been completed. The Tamar survey is the second of three new 3D seismic surveys currently being acquired in the company’s Southern Bonaparte Basin permits.
The 3D seismic surveys are being acquired within three of the Company’s six Southern Bonaparte Basin permits. The Company’s wholly-owned subsidiary, Goldsborough Energy Pty Ltd, holds a 100% participating interest in two of the permits (WA-407-P and WA-420-P) and a 60% interest in the third permit, WA-422-P, where the Rissa 3D seismic survey was completed in January 2012.
These new 3D seismic surveys follow the successful acquisition (during November 2011) of 2D seismic surveys in each of the Company’s other Southern Bonaparte Basin permits, WA- 421-P, WA-440-P and WA-441-P.
As with the completed 2D surveys, Seabird Exploration FZ LLC is carrying out the 3D surveys using the acquisition vessel, “Voyager Explorer”.
The Tamar survey acquired approximately 501 km² of new 3D seismic data, which substantially exceeds the WA-420-P permit’s Year 3 work obligations of 300 km² of new 3D data.
The Tamar survey area is only lightly covered by vintage 2D seismic surveying that is not presently sufficient to define trap closures. The survey area is located on the Tamar Nose within the WA-420-P permit.
The Tamar Nose is a north-east/south-west trending structural high that extends down into the Sahul Syncline source kitchen, and is seen as a natural focus for hydrocarbons migrating towards the southern Londonderry High. Indeed, three of the four wells drilled on the Tamar Nose have oil shows, while the fourth well, Tamar-1 drilled in 1979, was not located on a valid trap.
To the north of the Tamar 3D survey area are two vintage 3D seismic surveys; the Adventurer 3D and the Dunnart 3D. These vintage 3D surveys are expected to benefit from the modern reprocessing of this data that the Company plans to carry out as an adjunct to the acquisition of the new Tamar 3D survey. Together, the two (reprocessed) vintage 3D surveys and the new Tamar 3D survey will constitute 3D seismic coverage of an exploration area of over 1200 km², most of which is contained within WA- 420-P.
The target sandstone reservoirs are the Early Cretaceous to Late Jurassic, Sandpiper Sandstone, the Late Jurassic Elang Formation and the Middle Jurassic Plover Formation.
The Sandpiper Sandstone and Elang Formation/Plover Formation reservoirs are separated by the Late Jurassic Frigate Shale sealing marine claystones.
The Tamar 3D and the Kingfisher 2D surveys are linked in their endeavour to identify potential oil and gas targets along the Tamar Nose structural high.
That structural high extends through WA-420-P and WA-421-P from the inferred source of the hydrocarbons in the Sahul Syncline in the north-east. The interpreted migration pathway is along the Tamar Nose and into the north-eastern corner of the WA-421-P permit; as shown in Figure 2. The play extends from WA-420-P and into WA-421-P.
Subsea World News Staff , February 09, 2012; Image: Octanex