A blue gap is an enormous marine natural hollow or sinkhole, which is available to the surface and has created in a bank or island made out of a carbonate bedrock (limestone or coral reef). Blue openings commonly contain tidally affected water of new, marine, or blended science. They reach out beneath the ocean level for the majority of their profundity and may give access to submerged cavern entries. Notable models can be found in the South China Sea (Dragon Hole), Belize (Great Blue Hole), the Bahamas (Dean’s Blue Hole), Guam, Australia (in the Great Barrier Reef), and Egypt (in the Red Sea). Starting now, the most profound realized blue opening is Yongle Blue Hole.
