The permit encompasses the north eastern part of the Collins Creek Sub-Basin which also covers the eastern part of Application area 5/97-8 and the northern part of EP 391. The only valid well drilled so far in this sub-basin is Yulleroo-1 within EP 391, which recorded a small flow of wet gas. EP 428 contains approximately 40% of the Yulleroo Anticline.

Adjacent to this prospect, the EP 428 portion of the Collins Creek Sub-Basin also contains four other large structures with similar prospectivity to Yulleroo.

The Collins Creek Sub-Basin is essentially a sub-basin within the Fitzroy Trough, itself a major unit within the Canning Basin, and contains a thick sequence of marine deltaic shales and intercalated sands in the Carboniferous Laurel Formation which has only been validly tested by Yulleroo-1.

The company has commenced a detailed review of the existing seismic data within the permit and is in discussions with a number of parties in respect of a joint venture and the drilling of an appraisal well on the Yulleroo structure 2.5km south south east of the discovery well and within EP 391.