Time, water, and geologic forces have converged to create underwater sinkholes where oxygen-poor and sulfur-rich groundwater support prolific microbial mats resembling life on early Earth.

Following is a transcript of the video. Narrator: There's a massive underwater sinkhole off the coast of Belize that extends 125 meters into the Earth's crust. It's called the Great Blue Hole.

If you're looking to explore the hidden treasures below the surface, underwater cave adventures are as unique as they come ...

After reading about the fossils found in an underwater sinkhole in Florida, learn about 11 of the most unbelievable prehistoric animals. Then, read about Mexico’s Taam Ja’ Blue Hole ...

An curved arrow pointing right. The 'blue hole' was discovered among the Paracel Islands in the South China Sea. It measured just over 300 metres deep, surpassing the previous record of 202 metres ...

The world's oceans are home to many mysterious places that continue to intrigue and fascinate us. Here are five of the most ...

From above, this almost perfectly circular underwater sinkhole is a deep, dark bullseye amidst the electric blue waters and brilliant white sand bars that line the coast of Belize. Since renowned ...

"Sinkholes are most common in what geologists call, 'karst terrain'," the US Geological Survey explains. "These are regions ...

Further collection at the site will be a slow, ongoing process, given the logistical challenges of excavating an ancient sinkhole underwater. Still, the authors are hopeful about the fossils that ...