In Georgetown, Texas
Inner Space Cavern was discovered by the Texas Highway Department in 1963 as they were preparing to build this I35 overpass.
During the drilling process,
they found Inner Space Cavern.
Inner Space Cavern lies within the recharge zone of the Edwards Aquifer.
Figure from Musgrove (2000) after Burchett et al. (1986) and Brown et al. (1992); precipitation contours from Larkin and Bomar (1983).
This is the map view of Inner Space Cavern.
Map from Elliott and Veni (1994)
The dark gray areas indicate areas that were once open to the surface. These filled-in sinkholes are called bone sinks.
The passage walls show rock layers within the Edwards Aquifer. Limestone
Dolomite
The distribution of formations hints at water flow paths into the aquifer.
As the slightly acidic rain water passes through rock, it dissolves away calcite and enlarges cave passages.
Cave formations grow as the calcite is deposited.
Evenly distributed soda straws indicate diffuse flow.
Lines of stalagmites and stalactites suggest fracture flow.
Flowstone indicates a steady source of water over a long time period.
Science in Inner Space Cavern University of Texas scientists have set up experiments to study the relationships between water chemistry, drip rates, and how fast formations grow.
Calcite formations preserve records of the Earth’s history.
Scientists from UT analyze samples in order to investigate the relationship between climatic conditions and how quickly formations grow.
The oldest measurement of this stalagmite was found to be nearly 70 thousand years old. Musgrove et al. (2001)
Caves are filled with unanswered questions . . .
Q: Why does one fracture have formations while the other has none?
Lots of formations No formations
How did this happen?
Review Diffuse Flow
Soda Straw
Column
Fracture Flow
Helectite
Flowstone
Stalagmite
How you can help protect the cave? •
Remember, Inner Space Cavern is a LIVING cave. Touching formations or getting off trail will cause irreparable damage.
•
Keep the cave as clean as possible. Do not bring food, candy, gum, drinks, water bottles, backpacks, or strollers into the cave.
•
Stay with the group and listen to the guide. The tour is 1 ¼ hours long and several tours are in the cave at the same time.
Enjoy your adventure into Inner Space Cavern!