Not trying to steal your thunder, HDNitehawk, but seeing your photo of the Mammoth Hot Springs reminded me of another place in Wyoming with these interesting formations. Located in Thermopolis, WY, it's the place with the largest hot springs in the world.


The formations are quite old. The one immediately below is about 100 years old. They call the deposits travertine. The town is mostly built around these tourist attractions. It smells heavily of sulfur dioxide and other volcanic-like gases.


[img]/cfs-file.ashx/__key/CommunityServer-Discussions-Components-Files/24/4743.travertine.jpg[/img]


[img]/cfs-file.ashx/__key/CommunityServer-Discussions-Components-Files/24/4532.thermopolis.jpg[/img]