Even though it was a bright clear morning, there was still plenty of snow on the ground so we decided to postpone our visit to Mt. Rushmore and tour the underground passages of Wind Cave where there is no snow and the temperature, at a constant 54 degrees, was warmer than it was outside. Wind Cave National Park abuts the southern boundary of Custer State Park and is about 20 miles from our campground.
Our tour guide Ranger Mike.
Wind Cave is unique from many other caves in that it has less active water flow. Less water means fewer dripstone formations, or speleothems, such as the stalactites and stalagmites common in other caves. What Wind Cave does have is beautiful boxwork - a rare cave formation (95% of all the boxwork in the world is found within Wind Cave) - in greater variety and profusion than any other cave in the world.
The 6th longest cave in the world, based on mapped areas, it is estimated that only about 5% of the cave has been mapped. It was formed in one of the vast limestone layers underlying much of the area. Strong wind currents that blow alternately in and out of the cave are caused by changes in atmospheric pressure.
Here Ranger Mike is holding a plastic ribbon in the mouth of the original entrance to the cave and is demonstrating how the wind is drawing the ribbon into the cave. This is not the cave entrance that we used.
The Lakota Nation chronicles this opening as the place of emergence of their people to the surface of the world. Their creation story says they were beneath the surface and were led to the sunlight by Tokahe (the first to come).
The cave represents the buffalo's interior complete with organs, meat and medicines. After emergence, the Lakota saw the Black Hills were in the shape of a buffalo lying down and facing east, solidifying the relationship with "Pte Oyate" - buffalo nation, that still exists. It is still a sacred place and the red tobacco pouch in the tree is left as an offering.
Boxwork is a speleogen, formed before the cave itself.
One of the thousands (millions?) of cave holes, leading to other, unmapped passageways, found along the tour route of the cave.
This formation is called "popcorn". Popcorn forms as water rich in calcite beads up on the surface of cave walls. The calcite crystallizes and, given time, the crystals come to resemble a kernel of popped corn.
More popcorn.
Cave tour passageway.
More boxwork.
Pictures from underground.
After our hour and a half tour, we ate our lunch and hit the trail. Wind Cave promotes its 28,295 acres of rolling grasslands, pine forests, hills and ravines as much as its underground geological wonders. We put together a 4.5 mile loop trail along the Centennial, Highland Creek and Lookout Point trails.
This first part of the trail followed a stream-bed at the bottom of a canyon.
The bones of a small bison along the trail.
A huge ant-hill. All those dark things on the hill are ants.
We found the prickly-pear in South Dakota!
The last part of the trail follows the rolling hills of the prairie which had some spectacular views and...
one of the largest prairie-dog towns we have seen.
No comments:
Post a Comment