Top 20 Carnarvon Bedout Sub-basin Prospects Add Up to 1.5 bboe

Carnarvon Energy has highlighted the prospectivity of its acreage in the Bedout Sub-basin noting that the top 20 targets hold over 1.5 billion barrels of oil equivalent.

More than 100 prospects have been identified across Carnarvon’s acreage (WA-435-P, WA-436-P, WA-437-P, and WA-438-P, covering a broad range of play styles. The top five prospects in each permit have been re-assessed following the successful Pavo discovery this year, with the potential for high grading to drilling status. These top prospects contain both gas and liquids-focused targets.

“Given the success rate in the basin of nearly 70 percent, Carnarvon is confident the drilling of these wells will add to our already extensive resource base, providing potential future tie-backs to Dorado or supporting new standalone project hubs,” said Carnarvon's managing director and CEO, Adrian Cook.

“Several prospects are now being high graded as potential near-term drilling campaigns. Discussions are ongoing within the joint venture to determine where we focus our drilling, and we look forward to sharing those plans as they unfold.

All this exciting potential is underpinned by the Dorado and Pavo discovered resources of over 200 million barrels of oil and associated gas, with the development of the liquid the first step in unlocking the significant potential of the Bedout Sub-basin,” he said.

With its partner Santos, Carnarvon is high-grading Pavo, Ara, and Starbuck prospects for potential inclusion in near-term drilling campaigns. Potential future drilling campaigns are subject to the ongoing joint venture and government approvals.

Bedout Sub-basin exploration history

The March 2022 Pavo-1 discovery marked another exciting period of exploration in the Bedout Sub-Basin, following a string of successful wells between 2014 and 2018 including the Phoenix South, Roc, and Dorado discoveries.

Carnarvon recognized the promise shown by BP’s Phoenix-1 discovery in 1980 (which discovered around 10 million boe of gas in the Barret and Hove member sandstones) and the potential for 3D seismic to improve imaging and acquired the Bedout Permits in 2009.

The first 3D seismic acquisition in 2012 showed dramatic data quality improvement. Four out of the six exploration wells drilled in the 3D era of the past decade have encountered oil and/or gas condensate. This success rate of 67 percent from 3D-era exploration wells is world-leading.

In early 2022 Pavo-1 encountered a 196ft gross oil column, with 150ft of net oil pay. The reservoirs have high porosities, ~19 percent, and permeabilities in the range of 100 to 1,000 millidarcies. Initial analysis indicates light sweet oil with about 52 degrees API and a low gas-oil ratio. The 2C (unrisked best estimate contingent) resources are about 43 million barrels of oil.

Pavo-1 was drilled on the northern culmination of a pair of closures, Pavo North. Further low-risk upside exists in the undrilled southern structure, Pavo South. Interim analysis of rock samples and fluid samples acquired during the drilling has supported a review of the potential of Pavo South, and Carnarvon has upgraded the Pavo South Prospective Resource to 66 million barrels of oil (Pmean, gross) with an improved chance of success of 60 percent (Pg). This is in addition to the discovered oil in Pavo North.

Pavo represents a low-cost tieback opportunity to the planned Dorado development. Pavo is also significant in that it discovered hydrocarbons over 25 miles east of the Phoenix-Dorado Corridor, substantially de-risking and opening up the exploration potential of a very large area.

Following Pavo-1, the joint venture has been assessing prospects in the Bedout Sub-basin which have the potential to generate material further value through either tie-back opportunities to the Dorado project or as potential standalone development hubs.

Improved seismic data acquisition and reprocessing technology, combined with feedback from the growing number of wells drilled in the Bedout Sub-basin, has enabled the quality of information used to define future potential drilling prospects to improve.

To contact the author, email andreson.n.paul@gmail.com