Newly Discovered Amazon Reef Is SIX Times Bigger Than We Thought, And It Extends Into Oil Drilling Concessions

n shallower waters like here, the Amazon reef looks more as you might expect.

In shallower waters like here, the Amazon reef looks more as you might expect. © Greenpeace

The discovery of an extensive coral reef at the mouth of the Amazon River was one of the greatest finds of marine biology in recent decades. Unfortunately, the incredible revelation was rapidly colored with the news that the reef system also sat upon valuable oil and gas reserves.

Initially, it was thought that the reef stretched for around 1,000 kilometers (621 miles) down the eastern coast of Brazil, covering an area of close to 9,500 square kilometers (3,600 square miles). Many drilling concessions near the mouth of the Amazon – and not far from the reef itself – had already been sold off to the oil and gas companies BP and Total. It now turns out that the reef is much bigger than thought, and those concessions are smack-bang on top of it.


A new paper in Frontiers in Marine Science, which is based on the initial footage of the reef captured by Greenpeace back in 2017, has shown that the reef actually covers an area around 56,000 square kilometers (21,600 square miles), almost six times larger than originally thought. And so while Total thought they were going to be drilling some 8 kilometers (5 miles) from the edge of the reef, they’re instead going to be drilling right on top of it.

The blurry images don't look like much, but they show that the Total block is covered by rhodoliths. © Greenpeace

“To learn the Amazon Reef extends beyond our expectations was one of the most exciting moments of my research about this ecosystem,” says Professor Fabiano Thompson, oceanographer an at Rio de Janeiro Federal University. “The more we research about the Amazon Reef, the more we find. We still know so little about this fascinating new ecosystem and the knowledge obtained so far indicates any oil drilling activity could seriously harm this unique system.”

Taken from a different stretch of the reef, rhodolith beds are important for a whole host of marine life. © Greenpeace

The concession – known technically as a block – is located 120 kilometers (75 miles) off the northern coast of Brazil, and drilling rights were granted on the basis that Total's Environmental Impact Assessment showed that it would not interfere with the Amazon reef. However, a recent expedition that sent a rover down to the seafloor within the block to be drilled has shown that this is not the case, invalidating the impact assessment.

What they found instead were vast beds of rhodoliths, which are calcareous algae that grow on the seabed, along with many deep-water sponges that are typical of the Amazon reef. These provide extensive habitats for the fish, lobsters, and sea stars that call these parts home. The researchers are now calling on the oil company to cancel its project, while the Brazilian government is set to make a final decision as to how this will move forward in the next few weeks.


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