Cave Diving: Enter the Underground World
January 3, 2013
We’ll be covering all aspects of going through a full cave training in this ongoing series. If you have any questions about the process or equipment, please let us know in the comments.
How Are Underwater Caves FormedThere are a variety of ways that underwater caves are formed, but for most of the popular cave diving locations around the world, their origins are fairly similar. Australia, Florida, the Mayan Riviera region of the Yucatan Peninsula in Mexico, and parts of Asia and Europe are all considered to be some of the more popular cave diving regions. There are other cave systems throughout the world, but in the cases of Australia, Florida, the Yucatan, Asia and Europe, limestone is our key ingredient for cave formation.
Limestone is a relatively soft and porous rock. Over the years and various ice ages, the water level that we know has fluctuated greatly. At times, the caves we’re now familiar with were completely dry. Due to rain seeping through the porous limestone, channels of water formed over time, similar to the way the Grand Canyon was formed. As these channels grew larger, the rush of water helped to carve out the cave systems.
In more volcanic regions like Hawaii, you are likely to find caves formed via lava tubes. In some places, you may find sea caves that were formed when the seas were significantly lower and wave action eroded a hole in a shoreline cliff, which was then submerged as sea levels rose.
How Entrances to Cave Systems are FormedWithout an entrance to a cave, cave diving would be incredibly difficult! For cave diving, most popular entrances are located at sinkholes or cenotes as they’re referred to in Central America.
A sinkhole or cenote is a hole in the ground that leads to a cave. Typically, when water levels were higher, the underground flowing water pooled in various locations due to density of the limestone. In some places, large rooms formed and more limestone dissolved until the layer of earth that makes the roof became reasonably thin. When the water levels dropped, the weight of the earth roof was no longer supported by water pressure and it collapses, creating an entrance to a cave.