Brendan M. answered • 07/10/21
Professional Geologist in Louisville, KY area
When I was a tour guide at Squire Boone Caverns, I would have answered this by stating that touching formations would permanently stop formation growth. Consider that every time you touch anything you leave a fingerprint behind - oils from your skin. Think of fingerprints left behind on a clean glass. How would you remove the fingerprint? Typically you'd wash it with soap and warm water.
In caves the oils from skin will disrupt the flow of water over the speleothems. How long would it take for that oil to degrade or be washed away naturally. Unfortunately the link you provided didn't work for me, but I saw other websites stating that it would take 30 years to degrade.
The thing is, each cave and each formation in that cave is unique. There is a delicate dance of chemistry that allows formation growth. The problem is that formations grow so slowly that instantaneous impacts to formations cannot be immediately seen. This may be unsatisfying, but I think the right answer is... we don't know.
Perhaps you have water that moves over a formation quickly that would remove the oil in a relatively short amount of time. On the other hand, if you have a formation with slow moving water - a drip at a time - it may take much, much longer. And, perhaps, the damage would, indeed, be permanent.
As such, I feel that the thought to not touch formations for fear of permanent damage is not unfounded. Especially in a show cave that is visited by thousands of people each year. All things considered thought, even if touching a formation *only* stopped it's growth for 30 years, that's still a significant amount of time. And, that's only one fingerprint.
