Tag Archives: diving

Did You Know {64} ~ The Underwater River, Mexico

When limestone bedrock collapses, it sinks and forms a pit. Acting as a reservoir, this pit then fills with a mixture of fresh groundwater and saltwater. Eventually, organic matter ends up in the trench, and when it decomposes, it produces a halocline (a cloud of hydrogen sulphide) that separates the freshwater at the top from the saltwater below.