WHY did the Great Blue Hole appear?

Thanks to cave flooding.

Blue holes are sinkholes in the sea. The water inside such sinkholes looks darker than in the surrounding waters. During the glacial period, when the sea level was about a hundred meters lower than it is today, a system of calcareous caves formed in some parts of the land due to erosion. When the level rose, many caves were flooded, and their vaults collapsed.

The Big Blue Hole off the coast of Belize is the largest only in diameter (318 m). The depth of the sinkhole is only 124 m. The record depth belongs to the Dragon Hole in the South China Sea (301 m).

Categorized in: