Australia: Dorado-3 Baxter flow test beats expectations

Australian oil and gas company Santos has started a flow testing operation at the deeper Baxter reservoir of the Dorado-3 appraisal well offshore W. Australia. The initial flow results have exceeded expectations, according to Santos’ partner Carnarvon.

The Noble Tom Prosser jack-up rig; Source: Noble Corp.
The Noble Tom Prosser jack-up rig; Source: Noble Corp.

The Dorado-3 appraisal well – drilled by the Noble Tom Prosser jack-up rig – is located approximately 900 meters northwest of the Dorado-1 discovery made in 2018. The Dorado-3 well has been designed to boost the JV’s confidence in the subsurface characteristics and confirm reservoir productivity.

According to Carnarvon Petroleum, which owns a 20% interest in Dorado, the initial clean-up flow rate test over the Baxter Member at the Dorado-3 well was conducted over a twelve-hour period with the flow rate constrained by the surface well test equipment.

“The flow rate achieved a maximum possible measured rate of approximately 48 million standard cubic feet (“MM scf”) per day of gas and 4,500 barrels (“bbls”) per day of associated condensate through a 60/64” choke. This is equivalent to approximately 15,300 barrels of oil equivalent (“boe”) per day using Carnarvon’s 4.45 Bscf per MMBoe conversion rate for the Baxter gas. The well test was conducted over an approximate 7.4-meter interval of net Baxter reservoir and importantly was achieved with only 150 psi drawdown,” Carnarvon said on Thursday.

Expectations ‘comfortably’ beaten

Dorado-3 is planned to conduct two flow tests targeting the Caley and Baxter reservoirs, as well as acquiring full-bore core in the Caley, Baxter, Crespin, and Milne Members.

Once flow testing operations and data interpretation for both the Baxter and Caley reservoirs have been completed, Carnarvon will be in a position to provide guidance on the projected flow rates that could be expected for less constrained production scale wells.

Carnarvon Managing Director, Adrian Cook, said: “The initial results from the Baxter well test have comfortably exceeded our pre-test expectations, with the measured rates being at the surface equipment capacity, indicating the reservoir had the capacity to flow at significantly higher rates.”

“The well test has confirmed our assessment that the Baxter reservoir contains a condensate-rich gas capable of flowing at commercial rates with minimal impurities. This flow test information is important to the Joint Venture in terms of selecting a final concept for developing this project.”

The Baxter well test will continue for another 24 to 48 hours with multi-rate flow tests and pressure build-ups to gain further important reservoir information. At the completion of the current well test, the Baxter formation will be isolated and operations will start to prepare for testing the Caley reservoir. Current indications are that the Caley well test results will be available in around 10 to 12 days, Carnarvon said.

The Dorado-3 well is the second appraisal of the Dorado oil and gas field which was discovered in 2018, labeled the offshore discovery of the year. The field is located approximately 160km north-northeast of Port Hedland in the Bedout Sub-basin in around 95 meters water depth.

The Dorado-1 exploration well discovered hydrocarbon-bearing reservoirs in the Caley, Baxter, Crespin, and Milne Members of the Lower Keraudren Formation.

Santos, the operator with an 80% stake in Dorado, said in August that successful Dorado appraisal during the first half of the year resulted in a 68% increase in gross 2C resources to 310 million barrels of oil equivalent.

The field is located approximately 160km north-northeast of Port Hedland in the Bedout Sub-basin in around 95 meters water depth.

Offshore Energy Today Staff


Spotted a typo? Have something more to add to the story? Maybe a nice photo? Contact our editorial team via email.

Also, if you’re interested in showcasing your company, product or technology on Offshore Energy Today, please contact us via our advertising form where you can also see our media kit.