Researchers Send Underwater Drone Deep Into the Great Blue Hole — A Major Surprise Awaited Them

Beneath the blue surface of the ocean there lay places where the light faded and mysteries deepened. Some of the submerged wonders of the ocean were explored by divers and scientists, to unravel these secrets. This inquisitiveness led an underwater drone down the marine sinkhole off the coast of Belize, which revealed two bodies of people that drowned, Newsweek reported. The Great Blue Hole in the middle of the sea fascinated researchers and adventurers for decades. Though attempts to map its depths were made before, advanced technology helped get a better look. This discovery added another layer to the mysterious nature of this natural wonder.

The Great Blue Hole was located around 60 miles off the coast of Belize and was initially made famous by the explorer Jacques Cousteau. This massive marine sinkhole used to be a limestone cave system above water. It became submerged thousands of years ago with a rise in sea levels and created a circular abyss with a depth of over 300 meters into the Earth's crust. In December 2018, an important exploration was undertaken to delve deeper into its mysteries. This was led by a team of scientists and explorers, which included oceanographer Fabien Cousteau and businessman Richard Branson. The expedition deployed two submarines to navigate the depths and understand the sinkhole's formation, ecology, and environmental significance.

This mission was to map the interior and gather data on its geological and biological features. The use of submarines allowed for a comprehensive exploration, to attain insights that were previously unattainable. A dive to the bottom of the sinkhole revealed human remains from two people who died, along with a GoPro and plastic waste, according to Lad Bible. Three people were known to have gone missing in the hole, but the number of deaths was still unknown. The mission parameters found that after a particular depth, there was a distinct layer of hydrogen sulfide that separated the oxygenated upper waters and the dark, lifeless environment beneath.

Above this layer, the water was brimming with aquatic life which included various species of fish and corals. However, below the hydrogen sulfide layer, the environment did not contain any oxygen, which rendered the region uninhabitable for most marine organisms. This highlighted the unique chemical and ecological dynamics within the Great Blue Hole. "Anything that fell into the hole decomposed until that process used up all of the oxygen below 290 feet. That means that below the H2S, there's no oxygen and anything that falls there now is preserved,” said Erika Bergman, National Geographic Explorer and submersible pilot for Aquatica Submarines. "There were these odd tracks, crisscrossing circles right around the center of the hole," she added.

"Mostly it was quiet and dark down there. We also encountered the resting place for two of the divers who've been lost in the hole. We notified the local authorities, and everyone agreed to leave them undisturbed. They are at peace," Bergman added, as per News.com.au. The researchers also found hundreds of conchs and marks where divers had attempted to escape, old scientific equipment and a GoPro, with footage still intact. They recorded the presence of massive stalactites that had shifted positions, which indicated how the tectonic plates had moved the land. Preservation of such unique natural formations was important as they provided valuable insights into Earth's geological history and the processes that shaped marine ecosystems.