PWC Sun Valley August 23

Predicted too windy so the day was cancelled early, which meant we had all day to do other things.  I think some pilots went to Redfish Lake to hike the Elephant's Perch, but a bunch of us wanted to explore the ice caves near Shoshone.

The Shoshone ice cave is clearly a tourist trap but we decided it would be fun to see it anyways, and then compare it to a non-commercialized cave that Dean knew about.  The commercial ice cave does indeed have a lake of ice in it, and it is indeed around 0C in there despite being 30+C outside.  Apparently the flow of air through the rocks and the entrance cools the air and acts like a natural AC unit, keeping the cave cool enough for ice to form and accumulate.  In fact the staff have to keep draining water off the surface of the ice lake before it freezes and adds to the depth, otherwise the cave would completely fill up with ice and be inaccessible.

About to get down and dirty to access the T cave.

Then it was time to hunt down the non-commercialized caves that Dean had visited in previous years.  We ended up finding the "T-cave", so-called because this lava tube cave is in the shape of a T, with the entrance leading to a T-intersection that goes in either direction for ~1km.  Unlike the 0C ice cave, this one is at 15C so it's much better to explore in relative comfort.  This cave you have to enter via crawling before it opens up enough for you to stand up, and during the other parts of the cave you have to periodically crouch down and do a crab or monkey walk.  Big chunks of rocks in the middle of the lava tubes indicated that pieces of the ceiling *do* fall down, fortunately there was no earthquakes while we were exploring to send more pieces of the ceiling crashing down on us and sealing us in for eternity :)

The undeveloped T cave was especially interesting because of all the geologic oddities we found inside...high tide marks from the various lava flows, weird concretions on the floor and ceiling, calcium (?) deposits forming ribs, and the perfect half dome ceiling of the lava tube every so often.  Remarkably the entire cave system was free of vandalism or trash, as I think the small entrance and necessary crawling bit at the beginning discourage most casual visitors :) Oh yeah we also found an ancillary "bat cave" on the way back out; hopefully Dean got some good photos of them hanging from the ceiling.

My photos are here, but those with better low-light cameras will likely have better shots!

Dean has posted his photos here.