Mammoth Cave Kentucky

our trip to the Mammoth Cave National Park in Kentucky proved to to be more interesting than initially thought.  The enormous size and the variety of geological and human effects made our visit.  there are guided several trips into the cave and each explores a different section. 

the visitor center has this 3D depiction of the main cave area.  the cave was formed thousands of years ago by Green River flowing through and eroding the limestone deposits present in this area.  the sandstone deposits closer to the surface are harder and so they formed the cap for the cave.

additional to the 3D model the Park Service has this highlighted map which shows the full extent of the currently explored cave areas. there are over 400 miles of explored cave with spelunkers continuing to explore and add to the cave boundaries. 

this is the main entrance to the cave. descending the steps you can feel the cool air flowing up and out.

the main area is well marked with well defined paths to follow. this area is over 20 feet tall.

running several hundred feet and rising several stories high the name Mammoth Cave is aptly named.

the rubble seen here is from a collapse of the ceiling limestone.  the flat surface shown is the hardened sandstone.

the limestone does not always fall in small pieces. this huge rock fell from what looks like a pocket in the ceiling.

explaining why certain formations exist is impossible. this upside down mushroom formation is one of those. our ranger guide was unable to explain or even offer a theory as to why this was not washed awy when the the river flowed through this area.

this sigh was a warning to early explorers for the very narrow channel coming up.  the early guides had a strange sense of humor.

no one in our group was able to navigate this passage without touching both sides of the rocks.

before the Park Service took over the cave early explorers were led by entrepreneurial guides who would allow their charges to  use the smoky lanterns as pens leaving their mark on the ceiling and the walls.  this is euphemistically called 'historical graffiti' and is protected by the park rangers.

I wonder what Nick would think of today's guided tours?

early tourists came from all over the USA. O. Mull apparently came from Virginia.

the water channels between levels were supposedly formed by the river forming eddies and whirlpools which bored round passages as shown here.

these vertical channels could extend several feet.  this one appeared to be over 300 feet .

early Native Americans and later miners would visit the cave to harvest its nitrate for use in gun powder and other explosives.

one of the downsides of our touring this cave is the introduction of moisture and human waste into the cave. the increased moisture and added light from explorers all moss and lichen to grow on the cave walls.  the green showing in this photo is a moss variety.

gypsum is another mineral found in the cave.  these 'gypsum flowers' exist in several areas where the conditions are right. their unusual shape is unexplained. our guide said that these flowers grow very slowly and these were likely several hundred years old

our guide turned off all installed lights in our area and then used this old miners lamp to show what the early explorers would have seen. when he turned this off the darkness was absolute. film left exposed for 24 hours showed no exposure whatsoever. 

early explorers weren't concerned with recycling and left their trash.

a clearer picture of the limestone sandstone boundaries.

unlike many caves Mammoth Cave does not have an abundance of stalactites and stalagmites. this area is one of the exceptions.  the cascade of calcite drip-stone flows from the thin cracks between the sandstone and the limestone. the very thin vertical lines shown to the right-center   above are actually pencil thin, and very very fragile, mineral  deposits that run from ceiling to floor.

when you go down you must go back up.

not  all paths out required climbing 10-15 story stairs. one of our tours was in and out through the main entrance.

in an attempt to reduce the impact of man on the fragile nature of the cave the Park Service has installed air locks for tours into the deeper and more sensitive areas.

before the roads into this area were constructed tourists were transported via the Mammoth Cave railroad.  Coal fired steam engines (in black) would pull passenger cars (in red) to the area where guests would stay in tents.