Chevron Brasil Upstream Frade, in partnership with Brazilian Government agencies, will continue to work to contain the oil spill on its Frade field, offshore Brazil.

The spill occurred on 7 November 2011 when Chevron was conducting drilling operations at a targeted reservoir, and increased pressure caused a wellbore segment to open, thereby spilling fluid onto the ocean floor.

The remaining oil sheen, estimated at approximately 18 barrels in volume, is located 120km offshore Brazil, and is continuing to move away from the coast.

Chevron has deployed 18 vessels to support the well-plugging operations and sheen clean-up; the well was shut down as investigations to probe the cause of the incident began.

Country manager for Chevron Brasil Upstream Frade George Buck said the company is solely responsible for the incident and is committed to deploying resources until the sheen can no longer be detected.

The company is analysing data to estimate the total volume of oil released in the spill.

Drilling operations in the field have been suspended and production from the Frade field has been maintained at 79,000 barrels of oil equivalent per day.