Dredger used to collect sediment samples. The ship Esperanza is in Brazil for a scientific expedition to the Amazon Reef. Researchers and the Greenpeace team seek for more information on this unique biome. International oil companies want to drill for oil soon within a few kilometers of the Amazon Reef. However, experts warn that an oil spill in the area would irreversibly threaten the well-being of the ecosystem and people living in the coast.