Shell as operator along with co-owners Conoco, BP Amoco and ExxonMobil announced a significant sub-salt discovery in Mississippi Canyon Block 765. The Princess discovery is located approximately three miles north of the Ursa field, which is one of the largest deepwater fields in the Gulf of Mexico. Potential reserves in the new field are estimated to be in excess of 200 million barrels of oil equivalent. The discovery was spudded in April of this year by Noble Drilling's semisubmersible, Noble Jim Thompson in approximately 3,680 feet of water. The original hole was followed up by three additional sidetracks from the original wellbore to appraise the accumulation. The discovery well and each of the three appraisal sidetracks encountered hydrocarbons in several significant zones totaling about 300 net feet of pay. The Princess ownership is structured like that of Ursa and given the proximity to Ursa, the Princess reserves can be developed along with the continuing development of Ursa.