The Maclean-1 well will be drilled vertically and the operation is programmed for about 10 days, with a total depth of roughly 771 metres.

BSOC estimates that, in the event of an oil discovery at Maclean-1, the P50 or ‘most likely’ prospective resource of recoverable oil in the Maclean Prospect would be 77 million barrels, with an upside case (P10) of 135 million barrels.

The Maclean prospect is defined on 3D seismic data recorded for the Vic/P47 joint venture in January this year and is a downthrown fault closure located on the southern flank of the Flathead Anticline, downdip of the Moby Gas Field.

The main reservoir target is the Latrobe Group Kingfish Formation sandstone, which is the main producing reservoir of the Gippsland Basin oil and gas fields and which is expected to have good porosity and permeability at the Maclean-1 location.

“The occurrence of significant oil shows and extracts from the existing wells Moby-1, Flathead-1 and Whale-1, indicates that the Flathead Anticline received migrating oil at one time in its geological past,” BSOC said.

“The absence of amplitude anomalies over deeper parts of the Maclean structure would suggest that, if there is any petroleum present, it would likely be oil rather than gas.”

BSOC considers that trap sealing is the main risk at Maclean, with a lesser risk associated with potential biodegradation of any oil in the structure.

Participants in the Maclean-1 well and the Vic/P47 joint venture are: Bass Strait Oil Company, operator (ASX Code: BAS) 40%, Moby Oil & Gas Limited (MOG) 35% and Eagle Bay Resources NL (EBR) 25%.

While BSOC was operator for the Gilbert-1A well, it does not hold a participating interest in the Gilbert Blocks where that well was drilled.