Cenote Angelita is an advanced scuba diving cenote (water-filled cave) that has contains a hidden underwater river!
A pit is formed when the limestone bedrock collapses and sinks. It is then filled with a fresh groundwater and saltwater. When organic matter falls into the limestone reservoir and then decomposes, it creates halocline (a thin cloud of hydrogen sulphide) that causes freshwater and saltwater to seperate.
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