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The Great Blue Hole Mystery: Nature’s Deep Secret Beneath the Waves
For many years, scientists, explorers, and tourists have been enthralled with the Great Blue Hole, a captivating marine sinkhole off the coast of Belize. This enormous underwater chasm, which is 125 meters deep and more than 300 meters across, is a UNESCO World Heritage Site that is a part of the larger Belize Barrier Reef Reserve System. When viewed from above, it is an almost flawless dark blue circle that stands out sharply against the nearby turquoise shallows. This visual display suggests the mysteries that lie beneath the surface.
The Great Blue Hole was once a limestone cave system that formed during previous ice ages when sea levels were significantly lower. The sinkhole we see today was formed as the caves flooded and finally collapsed as the ocean started to rise. The Blue Hole’s depths remain mysterious despite its geological origins being known. Using contemporary submersibles, an expedition headed by renowned ocean explorer Richard Branson mapped the hole’s interior in 2018. They discovered amazing stalactites, odd microbiological life, and even a layer of toxic hydrogen sulphide that creates a dead zone about 90 meters below the surface where oxygen is absent.
