Australian firm Western Gas plans to commence drilling work at the Sasanof-1 exploration well offshore Western Australia in the first quarter of next year.

Located in exploration permit WA-519-P, the Sasanof Prospect covers 505km² and is on-trend and up-dip of Western Gas’ Mentorc gas and condensate field.

It is situated near the giant gas fields of Scarborough and Io-Jansz in the Carnarvon Basin.

According to estimates, the Sasanof Prospect contains 24 trillion cubic feet (Tcf) gas and 1.1 Billion bbls condensate (P50 GIIP).

Based on Western Gas estimates, the prospect has a geological chance of success of 35%.

Western Gas executive director Will Barker said: “Sasanof-1 marks an important milestone for Western Gas’ exploration activities, being our first exploration well to be drilled since the discovery of the Equus Gas Fields, which achieved an 88% rate of success.

“The Mentorc discovery in 2010 was a play opener for the Barrow Delta Front. It proved that the area contains world-class reservoirs with low CO₂ and high-quality gas and condensate.

“Building on the Mentorc discovery and armed with the latest 3D data and advanced geophysical techniques, Western Gas has been able to demonstrate that Sasanof has the potential to be another Giant Gas discovery.”

Barker anticipates the Sasanof well drilling success to change the dynamics of the greater North West Shelf.

Planned to be drilled to a total depth of around 2500m using Valaris MS-1 mobile offshore drilling unit (MODU), the Sasanof-1 well will be comprehensively evaluated.

Fluid samples will be recovered from the well to allow for the certification of resource volumes.

Following completion of evaluation activities, the well is planned to be permanently plugged and abandoned with the wellhead removed.

Currently, Western Gas is finalising an agreement with a listed firm to farm into Sasanof-1 to facilitate the funding.

Western Gas said in a press statement: “Upon success, a discovery of the estimated size of Sasanof will provide multiple gas supply opportunities, including domestic gas, LNG backfill and expansion, and new value-adding gas-led industries.”

The firm also awarded AGR Australia a contract to manage the Sasanof drilling campaign, which is estimated to cost $20m.