Ocean Monarch rig mobilizes to Otway to drill two wells for Cooper

Exploration & Production

Cooper Energy has said that the Diamond Offshore-operated semi-submersible rig Ocean Monarch has started mobilization from the Gippsland Basin to the Otway Basin offshore Australia where it is to drill two offshore gas exploration wells.

Ocean Monarch; Source: Quadrant Energy

As previously reported, Cooper hired the Ocean Monarch Annie-1 and Elanora-1 wells. The initial plan was to start drilling in June.

Announcing the rig mobilization to the Annie-1 well site offshore Peterborough, Cooper said on Monday that the two wells will be the first offshore gas exploration wells drilled in the Otway Basin in seven years.

The Annie and Elanora prospects, located in the VIC/P44 license in the offshore Otway basin, hold best estimate prospective resources of 71 bcf and 100 bcf, respectively.

Cooper Energy is the operator of the license with a 50% interest and Mitsui E&P Australia is its partner with 50% interest. The partners are drilling the wells to identify new sources of gas supply for south-east Australia.

According to Cooper, commercial discoveries resulting from the program can be economically developed through connection to the companies’ existing Casino Henry gas operations from 2021.

The Ocean Monarch is expected to arrive on location at the Annie-1 well-site, 9 km offshore Peterborough, around Wednesday, July 31. The rig is expected to be visible from the coast for the duration of the well which is forecast at 35 days.

The Annie prospect is a simple amplitude supported structure located seven kilometers from a pipeline tie-in point. The primary reservoir targets are the Waarre C and Waarre A Formations which are the productive reservoirs in the Casino and Minerva gas fields.

According to Cooper, the chance of finding gas and proving a minimum developable resource size at Annie is estimated at 56%.

On the other hand, Elanora is a large amplitude supported structure that straddles VIC/L24, VIC/L30, and VIC/P44, located ten kilometers west of the Casino gas field and approximately six kilometers to a pipeline tie-in point.

The prognosed reservoir, Waarre A Formation, is the same as the producing offset fields at Casino, Henry, and Netherby. The company believes that the chance of finding gas and proving a minimum developable resource size at Elanora is estimated at 44%.

Location of 2019 Offshore Otway Gas Exploration Program
Location of 2019 Offshore Otway Gas Exploration Program

Offshore Energy Today Staff


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