Erik Cordes, chief scientist of the Deep Search expedition, told the Huffington Post that the crew made the discovery on Thursday while exploring a site dubbed the Richardson Ridge. Hours after taking the team's submersible Alvin underwater, Cordes, alongside coral scientist Cathy McFadden and Alvin pilot Bruce Strickrott, surfaced with a variety of corals, including Lophelia pertusa.
L. pertusa is a stone-like coral typically found throughout the northern parts of the Atlantic Ocean. This species of coral is known for growing deep under the ocean surface and has previously been discovered off the coasts of Florida and North Carolina.
"This is a huge feature," Cordes told the Post. "It's incredible that it stayed hidden off the US East Coast for so long."
"Just mountains of it… we couldn't find a place that didn't have corals, " he added.
In the coming weeks, Cordes told the publication that a paper would be published on the team's "unbelievable" discovery.
Although the official stressed that the corals must be protected, the find comes as US President Donald Trump has issued proposals to expand offshore drilling in the Arctic, Atlantic and Pacific oceans.
The recent discovery was part of a two-week exploration of canyons, gas seep and coral ecosystems off the Atlantic coast, the Post reported. The work is part of a project by the US' National Oceanic and Atmospheric Administration (NOAA) to explore and map the Gulf of Mexico, Mid- and South Atlantic Bight, Northeast US/Canada transboundary area and international waters south of Bermuda.
According to NOAA, both expeditions are part of the Atlantic Seafloor Partnership for Integrated Research and Exploration campaign, an even larger operation between the US, Canada and the European Union to "advance knowledge of the Atlantic Ocean."