The joint venture of ENI Australia and Tap Oil Ltd. has agreed to surrender retention lease WA-34-R in the Bonaparte basin of Western Australia that contains the Prometheus and Rubicon gas discoveries.
Tap, the junior partner in the venture, said that the retention lease had been extended for a second 5-year term in 2015 and the JV had used this time to evaluate a range of commercialization opportunities under a variety of economic assumptions. They concluded that the returns on potential developments were not sufficiently attractive when put against the costs and risks.
The partners came to a mutual decision to surrender the lease, a move that was finalized on Dec. 24, 2019.
Prometheus and Rubicon, 3 km apart, were discovered in June and December 2000, respectively, by then operator Kerr McGee. Both fields have gas columns in the Upper Permian-age Tern formation – Prometheus 72 m gross thickness and Rubicon 30 m gross thickness. They lie in moderate water depths some 400 km west of Darwin and are in close proximity to the existing Ichthys-Darwin gas trunkline.