Impress told the market on Friday that VicPet was using the Ensign Rig-20 to drill the well to a total depth of 2100m, targeting 10.5 million barrels of in-place oil at the P50 level of confidence in the Lower Birkhead, Hutton and Namur reservoir horizons.

Recoverable oil volumes (P50) are estimated at 2.6 million barrels.

The Ascender prospect is 16km northwest of Santos’ Charo oil discovery and 25km north of the recent Growler and Wirraway oil discoveries made by the same joint venture in the neighbouring PEL 104 permit.

Impress described the prospect as a large low-relief four-way dip closed structure defined by a 2D seismic grid and is on a structural nose that plunges southeast into the Patchawarra Trough.

Covering 10.3 square kilometres, Ascender is one of the largest undrilled structures in the prospects and leads inventory in this region, Impress said.

VicPet and Impress each hold a 40% stake in PEL 111, while Roma has 20%.