A prospective resource of as much as 2.9 tcf of gas has been identified in a conventional Early Permian tight stratigraphic reservoir in the Mettika embayment of the southern Cooper basin in South Australia, said Senex Energy Ltd., Brisbane.
The next step, said Senex, is to optimize well design to achieve commercial flow rates and gas recovery in appraising the field, named Hornet, starting in September, but the confidence level is high because of strong well control and other factors.
The company said the Kingston Rule-1 and Hornet-1 wells confirm the existence of the reservoir at 2,500 m near gas pipelines that have spare capacity. The gas is low in carbon dioxide.
The two wells recently flowed gas at stabilized rates of as much as 2.2 MMscfd. The wells are in PEL 115 in which interests are Senex 80% and Orca Energy Ltd. 20%. The trap extends north, south, and east into Senex’s 100% owned PEL 516, and much of it is covered by 3D seismic and close-spaced 2D data.
Providing rigorous subsurface control are 37 wells that have been drilled in the Hornet field resource area by the South Australian Cooper Basin Joint Venture. Also, Hornet lies 7 km southeast of Kidman gas field and 15 km northeast of Toolachee gas field, both operated by Santos Ltd.
Senex said, “Interpretation of geological and geophysical data indicates the gas accumulation intersected by these wells has reservoir characteristics similar to many existing Santos-operated fields that produce conventional gas from the (Permian) Patchawarra formation” (OGJ Online, Nov. 29, 2012).
While the high estimate prospective resource is 2.9 tcf, the best estimated is 771 bcf and includes a 1C contingent resource of 141 bcf. Hornet lies less than 30 km from the Moomba-to-Sydney gas pipeline.
Hornet-1 was a cased, vertical proof-of-concept well that required a completion that could withstand 340° F. and 15,000 psi, said Packers Plus Energy Services Inc., Dubai, which participated in the frac completion.