Greenpeace members simulate an oil spill during a protest in front of the Chevron oil company headquarters in Rio de Janeiro November 18, 2011. Brazilian federal police have opened a probe into U.S. oil giant Chevron over alleged pollution linked to an oil spill at its offshore Frade project. Brazil’s energy regulator ANP said oil seeps off the coast of Rio de Janeiro were caused by a well drilled by Chevron at Frade, where the company has estimated as much as 650 barrels had been released causing a “sheen” on the sea surface. REUTERS/Ricardo Moraes (BRAZIL – Tags: DISASTER ENERGY CIVIL UNREST BUSINESS)