The bottom of the Atlantic Ocean has been burping methane for at least 1,000 years, scientists have discovered. NOAA surveyed the Atlantic Coast using sound waves and found at least 570 methane "seeps" from Cape Hatteras to Nantucket, right where the continental shelf meets the ocean, LiveScience reports. They found the methane in two forms depending on the seeps' depth—most are between 800 and 2,000 feet, reports the New York Times. Shallow seeps are coming from burping microbes, but deeper down it turns into a sludge called methane hydrate that releases the gas when it's warmed, the BBC explains.
The find is odd because methane seeps usually occur in "tectonically active" spots; the quiet East Coast is "cold, old, and boring," says study co-author Carolyn Ruppel, who adds that "we're setting the stage for a decade of discovery." Methane is a greenhouse gas, and the seeps could serve as a lab for studying climate change and its potential effects. The seeps aren't causing environmental concern—one expert says the amount of methane released is "probably on the order of a feedlot" and is dissolving in the ocean. In a biological side note, scientists have also found new life near the seeps—chemosynthetic creatures that get energy from chemical reactions and not the sun. LiveScience has photos of the methane seeps here. (More methane stories.)