When you visit this park, you will discover and learn about an eye-popping feature of Central Ohio. Did you know Dublin is home to a giant hole in the ground? If you're not a good student, you could find yourself sucked into the Kosciuszko Sinkhole! Come marvel at this vortex, if you dare!
Some of the country's most identifiable natural formations owe their existence to a geological formation which might be a foreign word to most people: karst. What exactly does "karst" mean? According to the United States Geological Survey, "karst is a terrain with distinctive land forms and hydrology created from the dissolution of soluble rocks, principally limestone and dolomite." The terrain is "characterized by springs, caves, sinkholes, and a unique hydrogeology that results in aquifers that are highly productive but extremely vulnerable to contamination." Although the average person may have no idea what a karst is, they are quite common throughout the country. Nearly 40% of groundwater used for drinking in the United States comes from karst aquifers! Two of the most famous natural areas in the united states - Carlsbad Caverns and Mammoth Cave - are karst areas. Without the karsts, these awe-inspiring cave systems would not be.
cross-section of a typical karst system
At the posted coordinates you see a sinkhole. Karst landscapes occur because mildly acidic waters slowly act upon soluble rocks. Water percolates through soil to the bedrock, where it interacts with fractures in the rock. Hundreds and thousands of years of pressure and chemical erosion from the water causes these fractures to grow. When the cracks become large enough that they cannot support the weight of the soil on top of them, a sinkhole forms. Sinkholes are natural depressions or holes in the Earth's surface. The result is an underground drainage system. The more work the water does, the bigger the drainage system becomes. One day, the fractures in the landscape become large enough that we term them caves.
a good example of a sinkhole
We don't often think of Central Ohio as a hotbed for cave systems or karst landscapes, but you see the telltale sign of the drainage system below the surface before your eyes at the posted coordinates. Here you will find signs that will give you additional information on the particulars of Dublin's karst landscape.
To log this Earth Cache answer the following questions:
1. Water acts upon rock below the surface to form karst landscapes. According to the sign at the posted coordinates, what type of bedrock lies below your feet in Dublin?
2. The Kosciuszko Sinkhole is not the only one in Dublin. According to the sign, what other two spots feature sinkholes?
3. Estimate the diameter and depth of the Kosciuszko Sinkhole. How long do you imagine water had to "work" on this spot for a hole of this size to form? How long do you imagine it will be until the system has morphed into something we would call a cave?
Click on my name on this cache listing and send me a message with your answers!
Although unnecessary for logging purposes, feel free to post a picture of you at the sinkhole!
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