Marcelo Calazans, Tamra Gilbertson and Daniela Meirelles*
In 2005, the Brazilian oil company, Petrobras discovered hydrocarbons below the geological salt layer in the Tupi field located in the Atlantic Ocean off-shore of Rio de Janeiro, Brazil. In 2006 a consortium of Petrobras, BG Group, and Petrogal drilled in the Tupi field and discovered an estimated 5-8 billion barrels of oil equivalent resources in a pre-salt zone. The pre-salt oil and gas lie below an approximate 2000m deep layer of salt, which is below an approximate 2000m layer of rock under 2000-3000m of the Atlantic. Further exploration found hydrocarbon deposits in the pre-salt layer extended through the Santos, Campos, and Espírito Santo basins located off-shore of Rio de Janeiro and Espírito Santo states.