Using sonar to explore deep-sea ecosystems off the coast of North Carolina, a team of researchers came across an 18th century shipwreck with several artifacts.

According to the Associated Press, the scientists were investigating an area called the Black Plateau when an unmanned underwater vehicle noticed the sunken ship. After realizing what they came across, the researchers notified the National Oceanic and Atmospheric Administration (NOAA) of their finding.

"This is an exciting find, and a vivid reminder that even with major advances in our ability to access and explore the ocean, the deep sea holds its secrets close," Cindy Van Dover, director of the Duke University Marine Laboratory and the expedition's leader, said in a news release. "I have led four previous expeditions to this site, each aided by submersible research technology to explore the sea floor - including a 2012 expedition where we used Sentry to saturate adjacent areas with sonar and photo images.

"It's ironic to think we were exploring within 100 meters of the wreck site without an inkling it was there."

The ship appears to have been made in the 18th century, based on observations archaeologists made from looking at photos. The NOAA's Marine Heritage Program plans to return to the site to explore it further, the AP noted.

"We have worked this study area for a number of years and never saw any hint of the wreck," Van Dover told the Raleigh News and Observer. "The deep sea is really vast, and this is kind of a gentle reminder that we barely have a glimpse of what's going on down there."