It is terrifying when sinkholes open up on land as they can instantly swallow whatever is on top. But they are not just confined to land. A similar phenomenon also happens in the ocean, creating mysterious blue holes that goes deep into the dark ocean.

These blue holes only open up in the sea, different from the underwater caverns of cenotes that exist under the land. Even so, the blue holes represent an opportunity for scientists seeking to learn more about the kinds of life forms and water conditions that occur in these marine formations.

Scientists Flock to Florida to See the Mysterious 'Blue Hole'

A team of scientists from different institutions is set to explore a blue hole next month called 'Green Banana' on the continental shelf off the coast of Florida as part of an ongoing three-year research project.

The team will comprise of researchers from the U.S. Geological Society, the Georgia Institute of Technology, Mote Marine Laboratory, and Florida Atlantic University. Meanwhile, the project sponsored by the National Oceanic and Atmospheric Administration (NOAA) will deploy divers and monitoring equipment into the Green Banana.

The glowing mystery hole is about 155 feet below the surface and about 425 feet deep.

It was surprising that the first to report the mysterious blue hole's existence were neither scientists nor researchers. They were fishermen and recreational divers who discovered the hole which appears to host diverse biological communities full of marine life.

The scientists are curious of what kind of microbes that live in the blue hole, and they want to measure the nutrient levels and assess whether the sinkhole is connected to the groundwater system of Florida adjacent to the Gulf of Mexico.

According to NOAA, the scientists discovered something at the bottom of the hole--two dead smalltooth sawfish, which is an endangered species. They recovered its remains for further investigation.

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Exploring Another Florida Hole

Scientists plan to go on a new mission after the August dive to investigate another Florida blue hole--the Amberjack Hole. Compared to the Green Banana, Amberjack Hole is significantly smaller with a rim that measures 113 feet below the ocean surface and about 237 feet deep.

"Blue holes are diverse biological communities full of marine life, including corals, sponges, mollusks, sea turtles, sharks, and more," the NOAA explains.

Moreover, it appears that the seawater chemistry in the holes is unique and interacts with the groundwater, and probably the aquifer layers as well. This links the knowledge of carbon cycling between surface and groundwater.

"The opening of a blue hole can be several hundred feet underwater, and for many holes, the opening is too small for an automated submersible," they added.

Whatever the scientists may find in their explorations, it is bound to add knowledge on the things that go on inside these holes hidden below the surface.

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