What is Karst?

You may not recognize the word, (it is Slovenian, after all) but if you live in the Austin area, there’s a good chance that you’re sitting on top of it right now. In fact, 15% of the Earth’s land surface is made up of Karst. So, what is it?
Karst is t
he geologic landscape, underlain by limestone, that forms caves, sinkholes, and aquifers through dissolution. If you dug 260 feet beneath the Austin streets, you would find the reservoir of water that much of central Texas relies on in one shape or form. Look around town and you'll see mentions of the Edwards Aquifer everywhere. Road signs, informational brochures, displays at springs and swimming holes. The aquifer is the underground water source that central Texans utilize for nearly all aspects of their water needs, even if many of us don’t realize it. 
Learn more about the Edwards Aquifer.

What Karst Looks like

Karst can be huge! Towering limestone mountains, Karst pinnacles, and colossal caverns. This photo is from China’s Halong Bay. While this image is a bit more dramatic than the rolling hills of central Texas, they are both examples of Karst.


What Karst Looks Like

Karst can also be small! Much smaller than this in fact. Karst may look like not much more than a crack in the rock. To the trained eye, a caver can discern between a void dissolved by water, and an animal burrow or pile of debris.