Last year, scientists made an amazing discovery under the mud and muck at the mouth of the Amazon River: a long-rumored 600-mile-long coral reef. Now the first images of the natural phenomenon are emerging, captured from a sub sent 720 feet down into the murky waters off a Greenpeace boat, the Guardian reports. The reef stretches from French Guiana to the Brazilian state of Maranhao, per a Greenpeace press release, and is astonishing researchers for its ability to flourish in dark waters. The Guardian notes corals tend to flourish in clear, sun-penetrating waters. That makes "this reef system important for ... the fact that it has unique characteristics regarding use and availability of light," a Federal University of Para researcher says, adding that the reef also holds "huge potential for new species."
But just as scientists have started to study the reef, oil companies have started to move in—and if Brazil's government OKs the permits they're seeking, these companies (including Petrobras, BP, and Total) will be able to start drilling in the area, the BBC reports. With drilling comes the risk of spills, and Greenpeace warns that some ecosystems such as the mangroves in Cabo Orange National Park won't be able to receive proper cleanup if oil does leak out. A Greenpeace Brazil activist reiterates the call to defend the reef, as well as the entire region, "from the corporate greed that puts profits ahead of the environment. One of Total's oil blocks is only [5 miles] from the reef, and environmental licensing processes are already under way." (The Great Barrier Reef lost nearly a quarter of its coral last year.)