A visit to the caverns offers you an opportunity to go back in time 140 million years. The more we know about caves, the more we can tell about geological history.
The more we see what nature has done and the time involved, the smaller we seem to be.
The caverns are part of the Glen Rose Formation, a shallow marine to shoreline geological formation from the lower Cretaceous period. This formation has been exposed in a large area beginning in South Central Texas, running north through the Texas Hill Country, ending up in North Central Texas.
All of this cavernous area of rock was once beds of silt, mud, and shell on the bottom of the sea. Erosion by wind and water eventually melted away material from the highlands and deposited it below the sea, sometimes several thousand feet deep. During the formative period of the earth, these mud beds were raised above sea level and dried out, cracking, much like a small mud puddle does, the mud shrinking and breaking into rough squares. This was the start of Cascade Caverns - the “lifeline” of a cave.
When water entered these tiny cracks it dissolved the soft material, enlarging some of the cracks. Later fresh water streams flowed through these cracks bringing vegetation and other organic matter from above, which rotted causing carbonic acid to form and eat away at the limestone, further enlarging the cracks. This action is still going on.
The minerals most common in Cascade Caverns are calcium, magnesium, and iron oxide (common rust). These make up the formations seen in the caverns when water flows through.
The most common formations in Cascade Caverns are flowstone on the walls and floors and stalactites hanging from the ceilings.
FLOWSTONE
STALACTITES
To get credit for this EarthCache, answer the following questions:
1. What underground river created the caverns?
2. How many waterfalls are in the caverns and where are they located?
3. Why is this considered a "living" cavern?
4. Pictures, although encouraged, are not required.
