Cooper Energy and its partner Mitsui E&P Australia have commenced drilling of the Annie-1 gas exploration well offshore Otway Basin in Australia.

Located approximately 9km offshore Victoria in a water depth of 58m, the Annie-1 is said to be the first gas exploration well to be drilled offshore in the Otway Basin in seven years.

The drilling follows spudding at the well using the semi-submersible drilling rig Ocean Monarch in the VIC/P44 permit, which is equally owned by Cooper Energy and Mitsui E&P Australia.

The well is the first in a planned two-well exploration program to be carried out by VIC/P44 joint venture to identify new gas supply sources for south-east Australia.

Currently, Cooper Energy and Mitsui supply gas from the offshore Casino, Henry and Netherby fields (Casino-Henry Joint Venture).

Utilising existing offshore infrastructure, the joint venture plans to develop potential commercial gas discoveries and process gas at the Minerva Gas Plant.

Planned to be drilled to a depth of approximately 2,330m, the Annie-1 well primary target is the Waarre C Formation, which is producing at the offset Minerva and Casino gas fields.

Cooper said that the secondary target of the well is the Waarre A Formation, from which Casino, Henry and Netherby fields produce.

The company said in a statement: “ The Annie structure has been mapped as a faulted ‘3-way’ dip closure, with a well-defined seismic amplitude anomaly and seismic inversion gas indications.”

The work program at the Annie-1 well is scheduled to be completed in 35 days, with the success work program including drilling, logging and plugging and abandonment.

Following the work program at the Annie-1 well, the Ocean Monarch rig is planned to be moved to drill Elanora-1 in VIC/L24.

Cooper noted: “Elanora-1 will test the largest, undrilled structure in the joint venture’s acreage and if successful will extend the proven gas fairway south of the existing producing fields.”

Cooper Energy starts three-well appraisal programme at Parsons oil field

Recently, Cooper Energy said it has commenced a three-well appraisal programme at the Parsons oil field, Cooper Basin, South Australia.

The work follows the spudding of Parsons-6 well by the PEL 92 Joint Venture, in which Cooper Energy has a 25% interest. The remaining stake in the Joint Venture is held by Beach Energy as an operator.