Acrasia–4 is due to spud in the middle of this month, Stuart said this morning.

If successful, a test of the basal Hutton could add about 500,000 barrels of oil in place (proved plus probable, or P50), the Adelaide-based company said.

An additional positive test of the Poolowanna Formation in the well could add a further 650,000 barrels to the field.

Century Drilling has been contracted to drill the well at the PEL 90 Candra Block joint venture in the Cooper Basin, South Australia.

The original oil in place is 3.4 million barrels (proven plus probable), Stuart said.

Acrasia–4 will have a total depth of 2,350 metres.and will primarily target the Hutton and Poolowanna formations, while the secondary targets will be the Birkhead and Lower Tinchoo formations.

Stuart rates its chance of success at 95%

Acrasia-4 will be drilled on the eastern end of the Acrasia oil field, about 160m east of Acrasia–1, primarily as a Hutton Sandstone development well.

The Hutton is the largest pool in the field with production currently only from Acrasia-3.

More than 100,000 barrels were produced from Acrasia-1 before the well became a Tinchoo Formation producer, Stuart said.

The company said the Hutton pool would be adequately drained by Acrasia-3 and 4.

Participants: Stuart Petroleum (operator) 75%, Mawson Petroleum (Beach)25%.