From the brains behind Brains On, this is the Moment of Um. Answering those questions that make you go, Moment of Um comes to you from EPM Studios. I'm Queenie Hayes, and I'm the most extreme golfer ever. Um.
As a self-identified extreme golfing enthusiast, I only golf in the most extreme places, like the Grand Canyon or the middle of Times Square. Oops, sorry. Sorry. Or even from the top of Mount Everest. Before. I really should have worn gloves.
Now that I've checked those off my list, I'm looking for even more extreme places to golf. Let's think. Where could I sink a hole in one? Donut holes? Pot holes? Key holes?
Meh, not extreme enough. Oh, what about sinkholes? Sinkholes are spots in the Earth's surface where the ground has collapsed and formed a hole. They can be small or hundreds of feet wide. Sometimes they're really deep or even filled with water.
Hey, how are sinkholes made anyway? My buddy Vivian was just asking about this. My name is Hazel Barton. I'm a professor of geology and I study caves. When a cave is very young, you have water coming from all different kinds of directions, coming together to where the easiest place is for the water to escape from the rock.
So it all kind of pours into one crack and that's the biggest crack. And then the water goes along that crack over and over again over the years and it gets dissolved. But while that process is happening, that crack is completely full of water. Water actually is pretty strong, right? If you've ever jumped into a swimming pool, you know, when you like hit the surface of the water, there's a lot of pressure pushing back against you to go underwater, right?
And it's the same when that cave is full of water. So the rocks in the ceiling and the higher pieces of rock above it are actually held up a little bit by that water as it flows through the cave. When you pull the plug and all the water drains out, you're not pushing up anymore. That's also how sinkholes formed.
Because if you can imagine if when the water drains out and that ceiling starts to fall away, if it's pretty close to the ground above, especially if you've got something on that ground, like a house or something, there's a lot of weight pushing down on the ceiling. So when the water goes away, that support goes away and then the whole thing kind of drops down.
If it's a really big sinkhole, that can drop all the way down and you can actually see into the cave. So there's lots of places in the world where that happens. You know, Carlsbad Caverns is an example of that, where you can see this really big cave entrance going underground.
In other places, the rocks that fall down actually fill up the cave that's underneath. So it's like the ceiling collapses and you get all this rubble and it's completely closes off the cave. And then you get a sinkhole that forms that we call a closed sinkhole. And sometimes if you work really hard, you can dig through the rocks at the bottom of the sink and you can actually find the cave. Um, uh,
Sinkholes are spots where the ground has collapsed into a hidden underground cave. They're more common where the ground is made of certain kinds of rock, like limestone or carbonate rock.
Those rocks can get eaten away by water over many, many years. So when it rains, water fills up these holes and slowly dissolves the rock, creating a big room underground. Eventually, the underground caverns can get big enough that they can't support the ground above, and part of the ground collapses in. That creates a sinkhole.
Hmm, come to think of it, maybe I shouldn't be whacking golf balls into caves and sinkholes. After all, how would I get my ball back? Hmm. Oh, oh, how about this bagel shop? There's gotta be tons of holes in here just perfect for golfing. Oops. Sorry!
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