Enauta Participacoes SA said Tuesday that a combination with 3R would create a company with a production potential of more than 100,000 barrels a day of oil and natural gas. 3R already is considering a potential combination with PetroReconcavo SA, another Brazilian oil producer that has oil fields on land. 3R rose as much as 7.3 percent in Sao Paulo, bringing its market cap to about $1.6 billion. The shares are up 27 percent this year on the news that it is a takeover target.