The Hanging Rock is the upper part of the Saluda Formation, a fine-grained, silty dolostone. The rock was probably deposited as a fine-grained lime mud in a warm, shallow marine sea not much different from the seas in the vicinity of the Bahamas. Later it was altered with the addition of magnesium to form the dolostone.
The Saluda is late Ordovician in age which makes it about 440 million years old. The rock itself probably formed over a period of a million years or so.
The process to form the Hanging Rock (the waterfall) is much more recent. As little as 500,000 years ago the Ohio River as we know it did not exist and this area extended smoothly from Indiana into Kentucky. One or two hundred thousand years ago a glacier sat on top of Madison and did not allow rivers such as the Kentucky to continue to flow north as they had. Instead, their water flowed west along the front edge of glacier, eventually (over several tens of thousands of years) carving the current Ohio River Valley. Over time, the waterfall retreated from its original position adjacent to the river to its present position.
[Information provided by Professor Pete Worcester, Hanover College Geology Department.]
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To log this cache: Take a photo (or photos) of Hanging Rock and post them here.
If you do not have a camera, you can still log this cache. Look on the BACK SIDE of the yellow and black road sign at the front corner of the wall. There you will find a sticker - what three colors are on it? Please e-mail the answers and DO NOT post them on the cache page. Thank you!
IN ADDITION: To comply with new earthcache logging requirements, please estimate the height of the waterfall and e-mail the answer to my geocaching account.