Golden Beach gas field lies at a water depth between 18m and 20m in the Gippsland Basin, offshore Australia.
The gas field is owned and operated by GB Energy, an energy company based in Australia. The company acquired the gas field in May 2018. Natural gas produced from the field will be sold to Origin Energy Retail, which will deliver the gas to Victoria and New South Wales for domestic and commercial purposes.
Golden Beach gas field is expected to produce gas for more than two years. Following partial depletion, the field will be transformed into a natural underground gas storage reservoir to meet the energy demand during peak periods.
Engineering studies are currently being conducted on the project, while gas production is expected to begin in 2021. The field is expected to produce up to 50PJ of natural gas in three years.
Golden Beach gas field location
Golden Beach gas field is located within the VIC RL1(V) permit area in Victorian state waters, which spans an area of 4.3km². The field is located approximately 3km offshore Ninety Mile Beach in the Gippsland Basin.
Golden Beach discovery and geology
The Golden Beach gas field was discovered by Burmah Oil Company in July 1967 by the Golden Beach 1A well, which was drilled to a depth of 2,905m. The well penetrated the Lakes Entrance Formation and discovered a small hydrocarbon gas deposit in the Cobia subgroup.
Golden Beach is a dry gas field containing no oil. The gas column at the field is approximately 32m-thick.
Golden Beach gas field development details
The Golden Beach gas field development includes offshore well drilling by using conventional drilling methods and construction of a new gas processing facility.
A pilot hole and two low-angle vertical subsea wells will be drilled directly over the reservoir to a total vertical depth of 650m. The wells will be drilled to suit both drawdown and storage activities. The wellheads will be installed with subsea Christmas trees.
A new 25km-long pipeline will be laid to connect the field to the existing gas processing facility in Longford, Victoria.
Pipeline details
A 5km-long subsea pipeline and a 20km-long onshore pipeline connecting to the onshore gas processing facility will be laid as part of the project. The high-pressure pipeline will reach onshore approximately 1.5km to the south-west of Golden Beach town. It will have a diameter of 28in and will be bi-directional to allow re-injection of the gas into the field for storage.
The subsea pipeline will be connected to an onshore valve station by a control umbilical, which will be laid in a horizontal directionally drilled shore crossing. It will include 25m-30m wide right-of-way and will be laid by trenching and lowering process.
Either a specially-designed rotary trenching machine or excavator will be used for the excavation of the trench. A trenchless construction method will be used to lay the pipelines at the areas crossing beach or shoreline.
Gas storage infrastructure of Golden Beach gas field
The partially depleted Golden Beach gas field will be transformed into a subsea gas storage reservoir featuring both injection and withdrawal facilities. It will enable refilling of the reservoir during the periods of low demand and withdrawal during the high-demand periods.
Additional equipment will be installed within the existing facility for compression and dehydration of gas for storage.