Taam Ja’ Blue Hole is at least 420 meters deep below sea level and may connect to a hidden system of caves and tunnels.
During an exploratory dive on December 6, 2023, aimed at determining the common environmental conditions at the Taam Ja’ Blue Hole in Mexico, researchers discovered that it is the deepest underwater sinkhole in the world, even though its bottom has yet to be measured. The new study was published in the journal Frontiers in Marine Science on April 29, conducted by Juan Carlos Alcérreca-Huerta, a postdoctoral researcher at the National Council of Science and Technology of Mexico, along with colleagues.
Known scientifically as karst topography, these blue holes are essentially vertical marine caves (also known as sinkholes) formed over thousands of years by glacial flow, with depths reaching hundreds of meters. They form when surface water seeps through rock, dissolving minerals and causing cracks to widen until the rock collapses.
The latest blue hole system was discovered off the coast of Chetumal Bay on the Yucatan Peninsula and has been studied by scientists through surveys, sampling, the use of sonar techniques, and many other methods.
New measurements show that the Taam Ja’ Blue Hole in Chetumal Bay, off the southeastern coast of the Yucatan Peninsula, is at least 420 meters deep below sea level. Thus, this structure is 146 meters deeper than the measurements recorded when it was first discovered in 2021 and 119 meters deeper than the previous record-holding structure – the Sansha Yongle Blue Hole, also known as the Dragon Hole, which is 301 meters deep in the South China Sea.
Blue holes found in waters with depths reaching hundreds of meters.
Notably, the Taam Ja’ Blue Hole has a slope of nearly 80 degrees, forming a large conical structure. The surrounding walls are made up of volcanic craters that protect the water inside the hole from tidal influences, creating completely calm flows and thereby establishing a wholly isolated habitat for the organisms within.
Unfortunately, despite their high biological value, very few scientists can conduct research on these blue holes. The reason is that tidal flow causes the water to be distinctly layered, with a layer of freshwater on the surface preventing oxygen from reaching the dense saline water below.
As a result, instead of oxygen, these blue holes are filled with toxic hydrogen sulfide gas that can be life-threatening for those who approach without proper equipment.
Images of the internal structure of the hole.
Despite the harsh conditions, blue holes are truly “oases beneath the ocean” teeming with organisms that have adapted to low-oxygen conditions. Furthermore, researchers believe that this lack of oxygen inadvertently provides a side effect that helps perfectly preserve fossils, allowing them to identify some long-extinct species.
In fact, underwater blue holes can provide vast amounts of information about both space and time. For instance, in 2012, during the exploration of a blue hole in the Bahamas, scientists discovered a type of bacteria living deep within caves where no other forms of life could survive. This finding has the potential to fill knowledge gaps about life forms that could exist on other planets.
