Last week we visited the “Devil’s Kitchen” along Plattekill Creek. That’s a very scenic stretch of the creek that reaches up to the very top of the Catskill Front. We visited one of the many waterfalls that are found along the creek, and we looked into its past. This area has been in the news lately as there are plans to restore the picturesque old stone bridge that is there. This week let’s go to that old stone bridge. It lies just a quarter mile or so east of the nearby old red cabin. The state has built a parking lot close by. If you park there then you can get out and find your way downhill and see a lot more beautiful landscape with some interesting geology. That speaks to us a lot more about the geological history here. Take a look at our photo.
A small tributary stream flows beneath that stone bridge. It has cut a deep rugged canyon right here. Look at that bedrock wall. It is vertical and very smooth and flat. It catches your attention, doesn’t it? It certainly needs some explanation. This is a special type of fracture that is called a geological joint. It has been described as something that occurred a quarter of a billion years ago, probably when Africa collided with North America. It took a while, but part of the deformation caused by this collision was this special type of fracturing. The bedrock throughout the Catskills was compressed but that did not deform it much. It was not the compression that rendered this rock unstable; it was expansion. And that was when Africa backed away. The compression was released, and the rock expanded. That’s when the joint fractures spontaneously appeared. We would like it if you took a good look at this image and remember to keep an eye out for more of these throughout the Catskills. These joint planes are relatively common.
They are also significant in the development of this beautiful site. For our purposes today, the important thing to know is that these joints played a big role in developing much of the jagged landscape up here at the top of Plattekill Clove. Those joints served as weak points in the mountain bedrock. Erosion is a process that is concentrated along streams. When Plattekill Creek was eroding and sculpting this landscape, it could focus on these joint planes of and that helped shape the rugged, almost vertical landscape up there. It must have been equally or even more effective when the glaciers were doing their work in this region. All in all, the result was this remarkable mountainous landscape, a landscape of cliffs.
We frequently try to give you a good excuse to go out and enjoy some of our fine scenery and our two most recent columns have been typical of those efforts. But the other excuse is that we will return here in each of the next several columns and learn more about the Devil’s Kitchen. There is a lot to learn here.
Contact the authors at randjtitus@prodigy.net. Join their facebook page “The Catskill Geologist.” Read their blogs at “thecatskillgeologist.com.”
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