Octanex Wraps Up Ascalon 3D Survey Offshore Australia

Octanex N.L. has announced that the last of three new 3D seismic surveys, the Ascalon 3D survey in WA-407-P, has been completed and the acquisition vessel, “Voyager Explorer”, has been demobilised. These new 3D seismic surveys have been acquired within three of the Company’s six Southern Bonaparte Basin permits.

The Company’s wholly-owned subsidiary, Goldsborough Energy Pty Ltd (Goldsborough), holds a 100% participating interest in the WA-407-P and WA-420-P permits, where the Ascalon and Tamar 3D surveys respectively were acquired.  Goldsborough also holds a 60% participating interest in the third permit, WA-422-P, where the Rissa 3D survey was completed in January 2012 – refer to the Southern Bonaparte Basin Permits & Surveys Location Map at Figure 1.

figure 1

These new 3D seismic surveys followed 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. Goldsborough holds a 100% participating interest in these three permits – see Figure 1.

The surveys were carried out by Seabird Exploration FZ LLC using the “Voyager Explorer” and all six surveys acquired more than their work obligation requirements. The overall programme acquired a total of 2168 km of new 2D data and  1186 km2 of new 3D data; well in excess of the 1850 km of new 2D and 800 km2 of new 3D required by the six permits’ work programmes.

The Ascalon 3D survey acquired approximately 426 km2 of new 3D seismic data, substantially exceeding the WA-407-P permit’s remaining Year 3 work obligation to acquire a minimum of 200 km2 of new 3D data. The additional Year 3 work obligation, to reprocess a minimum of 2000 km of existing 2D seismic data, was completed during 2011.

The Ascalon 3D survey area is located on a north-east structural trend between the Saratoga-1 and Ascalon-1 gas discovery wells in the western sector of the WA-407-P permit – see Figure 2.

The objective of the survey is to enable more precise mapping of both the Early Cretaceous Sandpiper Formation sandstone play and the deeper Late Permian, Tern and Cape Hay sandstone plays of the Hyland Bay Formation. Although gas was discovered in the Early Cretaceous Sandpiper sandstone in Saratoga-1, there is the possibility that oil may be present in the leads defined on vintage 2D in the Ascalon 3D survey area as, unlike the Saratoga discovery, they are not located directly  over the main structural fault that would have provided a conduit for gas to reach the Early Cretaceous Sandpiper Formation. The Late Permian is a gas play – see the WA-407-P New 3D Seismic Grid and Postulated Oil & Gas Migration Pathways Map at Figure 2.

Source: Octanex, March 13, 2012