Exxon Mobil has started oil production at the $4bn Julia oil field in the deepwater US Gulf of Mexico, with the first well already online.
The second well is expected to start production soon. The initial development phase of Julia is located 265 miles south-west of New Orleans in water depths of more than 7,000ft.
This phase has a design capacity of 34,000bpd of oil and uses subsea tie-backs to the Jack/St Malo production facility operated by Chevron.
Exxon Mobil said that the Julia development also included the use of subsea pumps with high design pressures.
At present, a third well is being drilled and is expected to come online in early 2017.
Based on production results, additional wells that are included in the initial development phase will be assessed.
ExxonMobil Development Company president Neil Duffin said: "Successful deepwater developments like Julia, located more than 30,000ft below the ocean’s surface, benefit from ExxonMobil’s disciplined project execution capabilities and commitment to developing quality resources using advanced technology."
"This initial production will provide ExxonMobil with insight into the potential future development of the reservoir."
Discovered in 2007, the Julia field consists of five leases in the ultra-deepwater Walker Ridge area of the Gulf of Mexico and is operated by ExxonMobil.
ExxonMobil and Statoil Gulf of Mexico equally own interest in the field.
The company has drilled 187 deepwater wells worldwide in water depths ranging from 2,100ft to 8,700ft, over the past decade.