Southeastern Minnesota is a textbook example of karst topography; a landscape formed from the dissolution of soluble rocks such as limestone, dolomite, or gypsum. The development of karst occurs whenever acidic water (formed as rain passes through the atmosphere picking up carbon dioxide which dissolves in the water) starts to break down the surface of bedrock near its cracks, or bedding planes. As the bedrock continues to break down, its cracks tend to get bigger. As time goes on, these fractures will become wider, and eventually, a drainage system of some sort may start to form underneath. Just such a “drain” had claimed the stream. The water may reappear miles away, perhaps seeping up through the bed of the nearby Root River, or maybe bubbling up in the woods somewhere as an artesian well or just your garden-variety spring.
Two weeks ago, while searching for the delicious but short-lived Morel mushrooms I knew grew in the area I came across a large maple tree that had previously been growing out of the side of the bluff, but was now lying horizontally across the water, a victim of erosion and windstorm. Behind it’s root ball, which was the size of a Volkswagon, was a small opening in the rock out of which blew a steady rush of air. It was the telltale sign of a cave, and a large one at that. Caves “breathe” as the air pressure on the surface changes. A falling barometer will cause the cave to “exhale” just as high pressure will refill the underground passages with outside air. I wiggled into the opening, a gently sloping passage, about shoulder width that twisted and turned for about thirty-five feet before widening enough to allow me to crouch, and eventually opening into a sizeable passage some ten feet high and three feet wide.
My heart was racing. You don’t find an undiscovered cave every day! I and my girlfriend Marie, who shares my love of exploration in general and caves in particular, immediately made plans to return with proper equipment as soon as possible, and that is where my story now picks up.
We come prepared with light caving gear, this is just supposed to be an initial reconnaissance, we’re not planning to push too far or too hard. But even so, we have followed proper caving protocol, and let friends know where we are and when we should be back. You need to fully understand that caves are not “safe” places. You can slip and break bones; you can fall off exposed cliffs or into pits; you can be crushed by falling rocks and collapsing passages; you can get trapped by floods; you can drown; you can get lost or stuck; you can die of hypothermia.
You just never know with caves.
We’ve got ropes, water, GO2 cameras, a little food and are wearing coveralls, boots, kneepads and gloves. It’s cold and muddy in caves, as previously noted. Some folks cave without gloves, but if you do so you’ll probably end up with dry, shriveled hands – cave mud does that. We also have small notebooks and pencils to map our progress and note any interesting leads or features, and, of course hard hats with LED lights, chosen for convenience.
I didn’t bring my old-fashioned carbide lamps which miners (and cavers) have used for generations. These lamps have calcium carbide placed in a lower chamber, the generator. The upper reservoir is then filled with water. A threaded valve or other mechanism is used to control the rate at which the water is allowed to drip into the chamber containing the calcium carbide. By controlling the rate of water flow, the production of acetylene gas is controlled. This, in turn, controls the flow rate of the gas and the size of the flame at the burner, and thus the amount of light it produces. An acetylene gas powered lamp produces a bright, broad light. Many cavers prefer this type of unfocused light as it improves peripheral vision in the complete dark. The reaction of carbide with water produces a fair amount of heat independent of the flame. In cold caves, carbide lamp users can use this heat to help stave off hypothermia.
I wriggle headfirst into the opening I had previously explored and soon reach the widened part of the cave. My partner follows, her waterproof LED lamp glowing in the otherwise impenetrable dark. It is a cool 48 degrees year ‘round in southern Minnesota caves and a lot of passages are dripping wet. This one is a “live” cave, still growing, water still flowing. Water is the lifeblood of a cave, dissolving the limestone here, redepositing it there. When water drips from the ceiling it leaves behind tiny traces of the dissolved rock, which over hundreds and thousands of years, builds up to form stalactites, and on the floor, where the water drips, stalagmites. It might take 100 years to add 1/4 inch of growth to a formation. Growing a cave is slow business.
We walk, crawl, slip and slide along the passageway for a couple hundred meters before coming to the end of the road, or at least the walkable part. The cave continues, evidenced by the air still streaming forth from a horizontal fissure about thirteen inches in height and maybe five feet wide. This is the stuff true cavers live for. The tight squeeze. The chance to push the cave another hundred yards. The possibility of a room with fantastic formations opening up on the other side. But it’s not for the faint of heart.
On January 30, 1925, while trying to discover a new entrance to the system of underground caves that were a popular tourist attraction in Kentucky, 27 year-old Floyd Collins became trapped in a narrow crawlway 55 feet below the surface. A rock had fallen in the tight passageway and lodged against his foot. The reports about efforts to save Collins became a nationwide newspaper sensation, and after four days during which Collins could be brought water and food, a collapse in the cave closed the entrance passageway to everything except voice contact. Collins died of exposure, thirst, and starvation after about fourteen days underground, three days before a dug rescue shaft could reach his position. Collins’s body was recovered two months later.
That story is always in the back of every caver’s mind when they venture underground.
I take off my belt that carries my gear and remove my hardhat. I can see that the space narrows farther in and will soon be too tight to keep them on. In warmer caves, I’ve heard of people taking off all their clothes to slip through a tight spot, but in the cold, wet spaces like this it’s not the best idea. You lose body heat too fast. I slide into the opening, crawling along, gradually inching forward. As I progress, the opening narrows until the only way I can proceed is to exhale and then push on. When I take a breath, my chest expands and I’m wedged in fast.
Ahead, out of the corner of my eye, I can see that the opening widens, and can catch tantalizing glimpses of crystal formations in the room beyond, the prize that will make it all worthwhile. I can hear falling water splashing into a pool(?) underground lake(?) So close and yet so far, but as I said tight spots are all a part of the game. Some would say THE part of the game that counts.
Jewel Cave in the Black Hills of South Dakota is the third largest cave in the world with over 177 miles of mapped and surveyed passages (as of 2015). Barometric airflow can be used to calculate the cave’s volume, leading people in the know to calculate its size at four to five billion cubic feet. The known cave only accounts for about 120 million cubic feet. This means there could be more than 95% of the cave still awaiting discovery, almost all of that in a remote part of the system accessible only after a series of very tight crawls about 1,800 feet long known as “The Miseries.” There are 1,100 feet of Miseries proper, followed by 700 feet of Mini-Miseries. The Mini-Miseries include 200 feet of belly-crawls, and tight spots like the Calorie Counter and the Funny Little Hole. It’s so tight, you have to decide which way you are going to turn your head before going in, because you won’t be able to change orientation until you come out the other side.
By comparison, Mystery Cave, which is Minnesota’s longest cave, has just over 13 miles of known passages. Who knows how big this hole in the ground is? It doesn’t end soon, the airflow tells me that. Mystery Cave is over ten miles away, but given the fractured nature of the rock around here, there’s always a chance that this cave might be connected to that one. There are numerous “leads” too small to crawl through that disappear into the rock and may (or may not) connect to undiscovered passages or the surface. Sinkholes abound in the area, a result of water draining into the earth, creating a cave and then collapsing. Or, they might just eke out a connection to a cave below. Raccoons and other curious surface dwelling creatures often leave footprints and other evidence of their subterranean explorations in parts of caves that don’t seem to have any way in or out.
Exhale, push forward, inhale. Exhale, push forward, inhale. I gradually inch along two feet. Ten. Twenty. And then, the passage finally widens into a room about ten feet across and seven feet tall. I call back to let Marie know and she starts working her way toward me (a little easier for her because she’s not as bulky as me) but it’s still tight. There’s some really nice “cave bacon” flowstone draped along one wall, so named for its resemblance to that porcine foodstuff. Striped because of different minerals being deposited in strips, it’s so thin you can illuminate it from behind and the light shows right through. Water is flowing along the wall at a pretty good clip a little to the right of the formation and when it reaches the bottom it runs across the floor and disappears into a crack. As I said earlier, caves form when water seeps into a fracture in the rock and dissolves the surrounding rock to form a cavern. The original crack is known as the cave’s “lifeline” and can often be seen running along the ceiling (the floor is usually too covered with mud and “breakdown” to show the lifeline below). Depending on the layers of bedrock, a cave may have multiple levels. Sometimes the limestone is sandwiched between harder layers of shale. Sometimes the upper level is created first, and then as the outside river cuts deeper into its bed water flows into the rock at a new, lower level creating a cave below the original cave. Surface water percolating down from above can follow the lifeline and create vertical connections between the different levels. There might be a cave below the room I’m in, or the water might just drain away through cracks. Judging by the rivulet of water vanishing below my feet, some serious erosion is going on here.
Clay Perry, an American caver of the 1940s, wrote about a group of men and boys who explored and studied caves throughout New England. This group referred to themselves as spelunkers, a term derived from the Latin spelunca “cave, cavern, den” itself from the Greek spelynks “cave.” This is regarded as the first use of the word in the Americas. Throughout the 1950s, spelunking was the general term used for exploring caves in US English. It was used freely, without any positive or negative connotations, although only rarely outside the US.
In the 1960s, the terms spelunking and spelunker began to be considered déclassé among experienced enthusiasts. They began to convey the idea of inexperienced cavers, using unreliable light sources and cotton clothing. In 1985, Steve Knutson (editor of the National Speleological Society (NSS) publication American Caving Accidents) made the following distinction: “…Note that I use the term ‘spelunker’ to denote someone untrained and unknowledgeable in current exploration techniques, and ‘caver’ for those who are.”
This sentiment is exemplified by bumper stickers and T-shirts displayed by many cavers:
“Cavers rescue spelunkers.”
The room I am in has some really nice formations, including a grouping of delicate soda straw stalactites hanging from the ceiling near the center. I walk over to take a closer look, they are nearly twelve inches long, maybe 75 or eighty of them in all. Soda straws are formed when water drips off the ceiling and leaves calcium behind just like all cave formations in this area, but these had the distinction of being pencil-thin and hollow, hence the name. The water drips down the inside of them rather than the outside as with most other types of formations. I’ve never seen so many together before, and rarely are they as long as these are. Usually the “straw” plugs up before they can reach too great a length.
As I stand here awestruck by their beauty, I hear a crackling noise from below, and glance down to see a network of cracks in the cave floor radiating out from my feet. Not a good sign, and before I have a chance to register my dismay, the whole floor collapses –sending me tumbling into a crevice below. As I fall, I bounce off the walls, and am struck by several falling boulders, tumble over a couple protruding stalagmites and land hard on a jagged pile of debris maybe thirty feet below. Instantly a piercing pain shoots through my back, and I know I’ve done some serious damage. In college, I was certified as a first-aid instructor, so I know enough to not try moving too much. I remember the story they told about a car accident survivor who was able to move his feet and had normal sensation in his body until a “good Samaritan” came along and dragged him to “safety.” He’s been paralyzed ever since.
My hard hat and lamp have landed on the floor some ten feet away, flooding the area with light. When I look up I can see Marie hurriedly completing the crawl and popping her head out. “Don’t step on the floor!” I call, perhaps stating the obvious. “Are you OK?” she asks. “Don’t know. I’m pretty sure I’ve got a serious back injury, but I can still move everything. No way we’re going to get me up and out through that squeeze with just the two of us, though. You’ve got to go for help, and fast.” “You’re sure you’re OK?” “I’m alive. I’m conscious, I’m not bleeding that I can see but I’m probably going into shock. Go get help!”
Realizing that time and cave temperature are not our allies, she replies, “All right” her voice choked with emotion. “Hang on, I’ll be back as fast as I can.” And with that she pops briefly out of the crevasse, turns end for end and wriggles herself back in.
Neurogenic shock is a type of shock (a life-threatening medical condition in which there is insufficient blood flow throughout the body) that is caused by the sudden loss of signals from the sympathetic nervous system that maintain the normal muscle tone in blood vessel walls. Injury to these nerves causes the walls of the blood vessels to relax resulting in slowing of the heart rate or bradycardia which can be fatal. Neurogenic shock is different from spinal shock; the latter means loss of function due to spinal injury which may be temporary or permanent.
I know all that, but knowing doesn’t stop it from happening. And given my situation, there is nothing I can do about it except to stay calm until help arrives. I try to get as comfortable as possible, but every time I adjust my position, a fresh jolt of searing pain courses through my back, so I’ll just lie as still as I can.
I figure fifteen minutes out of the cave, thirty minutes back to the car, twenty minutes into town. Probably an hour - maybe two, maybe three - to round up an experienced cave rescue team...they’ll probably have to gather their gear and come all the way from Rochester...
...but surely Marie will be back sooner than that.
Cave rescue borrows elements from firefighting, confined space rescue, rope rescue and mountaineering techniques but has also developed its own special techniques and skills for performing work in conditions that are almost always difficult and demanding. Since cave accidents, on an absolute scale, are a very limited form of incident, and cave rescue is a very specialized skill, normal emergency staff are rarely employed in the underground elements of the rescue. Instead, this is usually undertaken by other experienced cavers who undergo regular training through their organizations and are called up at need.
Cave rescues are slow, deliberate operations that require both a high level of organized teamwork and good communications. The extremes of the cave environment (air temperature, water, vertical depth) dictate every aspect of a cave rescue. Therefore the rescuers must adapt skills and techniques that are as dynamic as the environment they must operate in.
...but surely Marie will be...down to a bridge by a fountain, where rocking horse people eat marshmallow pies...everyone smiles as I drift past the flowers...
Whoa.
Losing focus, got to concentrate.
I’m cold, the light is getting dimmer, and according to my watch I just drifted off into la-la land for two hours. That’s a little disconcerting.
But Marie should be back soon. Help is on the way.
Help is...on...
Blacked out again, but this time I think my body has fought through the shock. I don’t feel so fuzzy-headed, which is good, because I’m going to need my wits about me. The pain is still there in full force, but it’s almost a welcome friend. It hurts so bad but maybe it will keep me sharp.
It’s been five and a half hours since Marie left for help and she’s still not back. Something happened. She slipped and fell. Ran off the road. Got lost in the woods. I’m trying not to think about it, but the minutes are dragging by and it doesn’t look good.
And inevitably, the light goes out completely.
There’s no dark as dark as it gets in a cave. Absolute blackness, you can’t see your hand two inches in front of your face. It’s kind of fun when the tour guide turns off the lights and you experience that total night, but the lights always come back on, right? Well, all I have is the light of my watch, and it’s a cold, blue light. A cold light in a cold night.
In the darkness every sound becomes amplified. Drip-plop, drip-plop, drip-plop, water dribbles from the stalactites. The sound of my own breath roars in my ears. And somewhere off in the bowels of the cave, a scrabbling and scratching, rocks falling. Probably a raccoon. A curious squirrel. If I get desperate enough and he gets close enough, he might end up as my next meal.
Another hour dragged by, and still no sign of help. The initial stages of hypothermia are beginning to set in, but I think that may be the least of my problems. Whatever is making the noises in the depths of the cave must have been sealed in here for ages, and now it’s getting closer. I’m shivering, and it’s not just from the cold. I can hear its labored breathing, a kind of slobbery, wet inhalation. A guttural cough, a low rumbling, growl. Heavy, shuffling footsteps. Closer now. Closer. That’s no raccoon.
And I don’t think he’s the one that’s going to be the meal.
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