Scientists searching for shipwrecks in the Gulf of Mexico instead found something they say no one has ever seen before.
The researchers from Texas A&M's Galveston branch had already found three shipwrecks roughly 175 miles off the coast. So they sent two remote-controlled vehicles to investigate what they believed was a fourth. But it wasn't quite what they expected.
KHOU reports, "So this is a very substantial asphalt volcanic structure ... a volcano of asphalt. Tar shooting from beneath the floor of the gulf, solidifying as it hits the near freezing water."
Researchers have nicknamed the structure "Tar Lily." It measures 20 feet in diameter and about 10 feet at its highest point.
According to the National Oceanic and Atmospheric Administration, "Although the asphalt volcano appears to be dormant for the moment, the size of the extrusions suggests that there may be more asphalt below that might get squeezed out in the future."
As for the shipwrecks, researchers a Texas A&M believe they likely sank together in a storm.
Researchers have found a variety of artifacts on the early 19th century vessels, including "navigational equipment, muskets, cannons, roles of suspected hides, tallow and even medicinal supplies like ginger used to treat sea sickness."
The age of the volcano is unknown, although colonies of coral growing on it suggest it's at least 100 years old.