September 29, 2010

Jewel Cave National Monument, South Dakota

Yesterday, we visited Jewel Cave National Monument. Discovered in 1900, when prospectors walking along a canyon felt a blast of cold air coming out of a hole in the rock, it was soon discovered that almost the entire cave was covered in a thick layer of beautiful white crystals. Jewel Cave also happens to be the 2nd longest cave described to date, with over 151 miles of mapped passages and several new miles discovered each year.

These prospectors hoped that these were jewels that they could make money off of. Instead, they soon found out that they were just calcite crystals that have no real financial value. But, this cave was realized to be somewhat unique, as few caves in the world have this kind of formation in such abundance. Thus, in 1908 Theodore Roosevelt designed this cave as a national monument.

We took the Scenic Tour, which is 80 minutes in length and requires walking over 760 steps. Even though Hilina absolutely loves caves and we've taken her on a couple of cave tours already, we decided this one wouldn't work for her due to the length of time and the fact that there are no bathroom options, food or drink allowed. We decided to save Wind Cave for her. Instead, we went separately. I took Hilina for a hike on the surface while Linda went and then I went on a later tour.

Jewel Cave was form in several stages...First there was the great shallow sea that deposited the limestone about 300 million years ago. Then, about 60 million years ago, as the Black Hills were lifting up above the surrounding plains, the pressures created cracks and fissures in the limestone. As water trickled down into these fissures, it dissolved the limestone to create the cave passages that we see today.

At this stage, the cave was like thousands of limestone caves around the world. What made it special was that at some point, the springs at the bottom of the formation that drained this water plugged up and the entire cave was inundated with water supersaturated with dissolved calcite. Anyone who has had chemistry knows that if you have a supersaturated solution, the minerals will precipitate out as crystals. Thus, the calcite began to deposit onto the surface of the cave as crystals 6-18 inches long.

The cave also has a number of other really interesting and unique formations, but the 80 minute tour we took didn't take us to those. We needed to go on the "wild cave tour" which requires squeezing through some very tight spaces!

On the surface, the entire area was inundated by a major wildfire back in 2000 called the Jasper fire. it did not affect the cave and infact, the park placed all of the computers and important documents in the cave for protection in case the visitor center burned down (which it didn't).

View from Visitor Center

They have been doing prescribed burns in the area to prevent the risk of catastrophic fire in the future.

Hilina really enjoyed hiking down into the limestone canyon and looking at the pinkish-orange walls, since as she always says "pink is my favorite color". She also kept saying "This place is beuzital", her was of saying beautiful.

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