Carnarvon Energy Ltd (ASX:CVN) is taking steps to unlock further oil and gas resources in the Bedout Sub-basin offshore Western Australia with evaluation of 3D seismic data resulting in an unrivalled spread of highly attractive prospects.
This interpretation work has led to the joint venture (JV) targeting five strategic prospects containing a combined material resource of 623 million barrels of oil equivalent (gross, unrisked Pmean).
These prospects are within Bedout Exploration Permits (EP) WA-435-P, WA-436-P, WA-437-P and WA438-P, with CVN managing director and CEO Adrian Cook describing the sub-basin as “Australia's most prospective and exciting offshore exploration acreage”.
Five prospects high-graded
The five prospects preferred for further exploration are Ara, Wallace, Wendolene, Starbuck and Pavo South with these being high-graded for future drilling campaigns.
They have been strategically selected for their potential to build resource scale, de-risk significant prospectivity within nearby clusters and strengthen a number of development opportunities.
The gas opportunity within each of the five prospects is significant and presents an attractive case for the Dorado Phase 2 development being matured by the JV.
Providing further encouragement is that nearby upside of 7.78 trillion cubic feet of gas and 1.25 billion barrels of oil has already been identified, with such scale being rare within the Australian energy sector.
“Substantial prospective running room”
Cook said: “As evidenced by Carnarvon’s recent partial divestment of a 10% interest in its Bedout assets to CPC Corporation, Taiwan, the Bedout Sub-basin represents Australia's most prospective and exciting offshore exploration acreage.
"The latest interpretation results emphasise the substantial amount of prospective running room to be had if any one of the identified resource clusters are successful.
"As we progressively evaluate the latest 3D seismic data, we have the difficult task of deciding which of the high-graded targets to drill first across a plethora of highly attractive opportunities.”
Five high-graded well targets and the related clusters which would be de-risked in the case of a successful well.
New Bedout data
In the past 18 months, a large amount of new data has been added to the JV’s Bedout database, including:
- final processing products for the Phase 1 and Phase 2 Keraudren North Extension 3D data sets acquired in 2021 and 2022 respectively;
- Dorado multi-azimuth (MAZ) seismic processing data set, which combined the Keraudren, Archer and Capreolus 3D seismic data sets over the Dorado Field and surrounding acreage;
- large areas of the original 2014 Capreolus 3D data that have been reprocessed for improved prospect definition;
- multiple Quantitative Interpretation (QI) and seismic inversion projects, which aim to predict lithology and fluid content away from the well bore through amplitude analysis; and
- Pavo-1 and Apus-1 post-well analysis, which significantly strengthens sub-surface understanding.
Ara prospect, in the northern half of the WA-435-P EP, is a prospective resource that could contain 549 Bscf of gas and 91 million barrels of condensate (Pmean, gross). Prospects within the Ara Cluster include Bandy, Yuma, Bara and Wiwaxy.
With a robust 37% chance of geological success, Ara could form the basis for a new gas-centric cluster in the north of the Bedout Sub-basin and significantly de-risk nearby prospective resources contained within a concentric gathering system.
Similarly, the Starbuck prospect aims to target 113 million barrels of oil and significant associated gas. It boasts an attractive geological chance of success of 58%.
Success at Starbuck would encourage new oil development in the east of the WA-436-P Exploration Permit. Success would equally de-risk the identified Fall Line, Coho, Tacoma, Stampeders and many other prospects, all of which could feed into a future Starbuck development project.
Three additional areas have been identified by the JV around Wendolene, Wallace and Pavo South, with the Wendolene and Wallace clusters primarily gas-focused and the Pavo South cluster more liquids-rich.
The Wendolene area includes prospects such as Mensa, Murray and Avoca. The Wallace area has opportunities like Sampati, Bottlebrush South and Calendula North, and nearby Pavo South are the Torin, Orona and Taurus prospects.
Future drilling
The JV has plans for further exploration drilling in the Bedout EPs in the medium term.
Discussions have been maturing with respect to securing drilling slots on a semi-submersible drilling rig to drill two or three wells in the WA-435-P, WA-436-P and/or WA-438-P EPs.
The precise timing for the next round of exploration drilling in these EPs is dependent on the timing for regulatory approvals and particularly the new consultation process relating to the preparation of environmental plans as well as customary joint venture approvals.
Carnarvon cautions that prospective resources are the estimated quantities of petroleum that may potentially be recovered by the application of a future development project(s) and relate to undiscovered accumulations. These estimates have both a risk of discovery and a risk of development.