Peer Inside a Mysterious Blue Hole in the Great Barrier Reef
The geological formation reaches down 100 feet, and its contents can only be seen by diving below the surface.
Great Barrier Reef Blue Hole Filmed For First Time Ever
By Sarah Gibbens
PUBLISHED December 13, 2017
National Geographic produced this content as part of our partnership with Rolex, formed to promote exploration and conservation. The organizations will join forces in efforts that support veteran explorers, nurture emerging explorers, and protect Earth’s wonders.
Of all the names given to geological formations, "blue holes" have perhaps the most straightforward. For marine researchers, however, they're anything but. The watery sinkholes hold treasure troves of information.
https://news.nationalgeographic.com/2017/12/underwater-blue-hole-explored-great-barrier-reef-video-spd/
