I want to share an experience with you that really bowled me over—but I know next to nothing about geology, and I’m not sure I can talk about it in a way that’s meaningful. Maybe it’s just one of those “you had to be there” places.
(So I’m thinking: duh, I won’t just talk about it, I’ll share some photos! Of course, pictures don’t come close to the experience of being there either, but they can make an impression. Plus, I’ll find someone who does know what they’re talking about, then just try to boil up what they said in plain language.)
Carlsbad Caverns National Park, in the Guadalupe Mountains of southeastern New Mexico, is one of those “you have to see it to believe it” places. It’s the most visually stunning, the most other-worldly cave system we’ve visited.
You can’t look at the place without wondering how on earth it happened! If you want a little geology… (if not, skip ahead!) going back roughly 250 million years, lots of marine life died and built up a limestone reef along the edge of a vast, shallow inland sea. (The sea is long gone, but standing on the cliffs above the cave entrance you can look out and sort of picture it.) Later, hydrogen sulfide gas, escaping from oil deposits far below, combined with microbes and with oxygen in the water table, forming sulfuric acid, which dissolved and created underground cavities in the limestone. Then, “just” 3 million years ago, as the cavities grew into caverns, water slowly drained and roofs collapsed, exposing caves to what we think of as air. Formations grew as limestone-laden ground water dripped into the carbon dioxide-rich caves. (An intriguing thought: because the caves were dissolved deep underground, many don’t have an opening on the surface. Think of what still lies undiscovered!)
The result is large caverns with bizarre “decorations”, what geologists call speleothems—formations with names both foreign and familiar: stalagmites (which grow up from the ground) and stalactites (which form down from the ceiling), flowstone, popcorn, soda straws and draperies.
One cool thing about Carlsbad, unlike other caves we’ve visited, is that you can explore the main caverns on your own, so you don’t have to go with a tour crowd. If you want to get dirty though, there are ranger-led excursions in parts of the caves where you crawl through tiny tunnels; you have to promise you’re not claustrophobic.
It’s hard to show just how steep the first drop into the caverns is—you walk into a hole in the ground, with switchbacks that take you hundreds of feet down before the path starts to level out. (I guess that’s better than the early days when they lowered you down the hole in a bat guano bucket.) You work your way down through a labyrinth of chambers; the biggest caves are 755′ down.
The main attraction is called the Big Room—I assume the first (white) explorer was struck dumb and couldn’t do better than that. The name’s accurate anyway; it’s about 8.2 acres in size (6.2 football fields would fit inside of it!) and it’s 255’ to the highest ceiling point. Some formations are up to 62’ high.
The light’s pretty dim down there—taking pictures requires a longish exposure. Not surprising when you think about what it took to bring electricity into these strange nooks and crannies hundreds of feet underground.
Not all of the action took place millions of year ago; there are still some speleothems—about 5% of them—that are growing. When you feel water dripping on your head, that’s a clue. The changes may be too slow to be detectable in your lifetime though.
But your lifetime should be long enough to find a time to get down to see this weird place under your feet. You don’t need to understand the geology of the place to be so happy you saw it.
All photos: © 2015 Sue Cummings and Bruce Howard. All rights reserved.