Earth Science


EARTH MATERIALS AND SYSTEMS As you read, note how caves are formed by weathering and erosion.


The water is warm, and you’re wearing a wetsuit. Still, you shiver as you dive in. Is it fear or just excitement? You’ve never been to an underwater cave before. A cave is a natural hollow in the


ground. It’s large enough for a person to enter. Most caves are found in areas of limestone rock. T is cave is a cenote, or sinkhole. Gran Cenote formed more than 6,500 years ago when a section of the cave roof collapsed.


Gran Cenote, Mexico Here, divers have discovered more than


300 kilometers of fl ooded pathways and caves. Explorers who have gone before you have fixed ropes into the cave walls. T ese ropes are your road map. By following the rope guidelines, you


can swim through narrow passages and large rocky rooms without getting lost. Your tour of this cenote is only the first of many diff erent caves you will get to explore on this adventure.


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