Initial production should exceed 100,000 barrels daily but full-scale extraction is unlikely until 2013 and will likely be very expensive to develop.
The Tupi field lies under 2400m of water, almost 3300m of sand and rocks, and then another 2,200m thick layer of salt. The company drilled test wells that lie under 2300m of water, 283km south of Rio de Janeiro.
This compares to the Grand Banks (Hibernia) where the water depth runs about 80-110m and the Orphan Basin where the water depth ranges to 2500m.
Media reports on the Tupi field are available here and here. The story of a previous large discovery can be found here.