If the fear of sharks keeps you from taking a Caribbean vacation, be aware that there's a far greater threat lurking beneath the waves of this popular destination. The region is riddled with volcanoes and hidden earthquake faults that amount to a potential powder keg, with the power to create earthquakes and tsunamis without warning.

In the new Nat Geo Wild special "Caribbean's Deadly Underworld with Bob Ballard," premiering on May 18, the National Geographic Explorer-in-Residence who discovered the R.M.S. Titanic investigates these underwater threats, zeroing in on the volatile Puerto Rico Trench, the deepest point in the Atlantic. It's quite possible that a killer tsunami like the one launched by the 2004 Indian Ocean earthquake could happen there.

"The Caribbean plate is active along of four of its boundaries, characterized by earthquakes and volcanic eruptions both of which can generate tsunamis. It is not a question of if these violent behaviors of the earth are going to occur but when and where," says Ballard, noting that "the potential impact can vary as it has in the past in Haiti, for example, resulting in a tremendous loss of life and property.


But Ballard, who spent four months on an expedition to the area scouring the ocean floor with remote-controlled submersibles, found more than evidence of landslides and collapsed volcanoes. He discovered that there is a vast amount of sea life thriving in total darkness, miles beneath the ocean's surface. "The biggest surprise during our four-month long expedition was the discovery of an entire new and unexpected communities of life created by a large landside west of Grenada," including colonies of shrimp, lionfish, and enormous mussels.

“These new ecosystems appear to have been created when the landside compressed the organic rich sediments as they tumbled downhill driving out methane gas which chemosynthetic organisms used to fix carbon to create an food chain independent of the sun," Ballard explains. "No one had ever expected this to occur at the base of landslides beneath the sea, for which there are countless other examples around the world's ocean basins."

With so much more explore, "We will continue working in the Gulf of Mexico and Caribbean Sea this year before heading into the Pacific, where we expect to remain for many years," notes Ballard. Nat Geo Wild will follow his journey of undersea discovery starting on June 11 in high-definition streaming video via Nautilus Live.

Related on MNN:

Titanic explorer investigates the 'Caribbean's Deadly Underworld'
"Caribbean's Deadly Underworld with Bob Ballard" investigates such underwater threats like volcanoes and hidden earthquake faults.