If you want a challenging drive, right here in our Catskills, then take the Plattekill Clove road (Greene County Rte. 16) all the way from its bottom to its top. It’s steep – very steep – all the way! You may very well find yourself past people who are riding uphill on bicycles. It’s hard enough to drive up the hill, but how on earth do those people peddle this slope!? To make it even worse (if that is possible) there is, about halfway up, a very sharp hairpin turn. You will find a few parking spaces just past that turn and it’s worth it to stop and get out. Catch your breath and walk back downhill about 50 yards. Look up and you will find a very good view of the clove. Take a look at our first illustration. That’s the “Devil’s Kitchen” up there; we have been visiting that site these past two weeks. There’s hardly a geologist anywhere who would take in this vision and not soon think about a very common process in landscape geology – that is something called headward erosion. That’s something that you should be aware of.
Every stream on the planet has something called its head. That is its extreme uphill end. That’s also commonly called the stream’s source. Well, there is something that you should know about that uphill end of a stream. That’s the steepest part; in fact, streams almost always get steeper as the head is approached. See our illustration; it shows all this quite clearly (We waited until the shadows were just right). You might guess what we are going to say next: the uphill end of any stream is very likely to be its most erosive part. Water currents, rushing down those slopes, tend to cut deeply into the underlying earth whether it be soil or bedrock. At Plattekill Clove this intensively erosive zone is the Devil’s Kitchen.
Take another look at our illustration. There must be a lot of erosion going on up there. There is and we have been describing that recently. Now think far into the future. Yes, that stream, Plattekill Creek, is going to cut farther into this, the Catskill Front, and work its way westward. There is something else; that uphill slope is the youngest part. And it shows. Geologists long ago recognized that young stretches of streams tend to be narrow and V-shaped. That’s what we are looking at here. As time passes, streams erode down into the earth, and they also tend to widen their valleys. We often think of them as becoming more “mature.” A stream matures in a downhill, downstream direction.
We are looking at the origins and then the longtime development of one of the Catskill Front’s major canyons: Plattekill Clove. Long ago, at the end of the latest Ice Age, Plattekill Creek first formed and began cutting its way into this, the Wall of Manitou. At first, it was just a short, narrow and small canyon. Later it got longer, deeper and wider. But there was always that youthful uphill stretch at the top. That marks a fundamental change. Everything to the west is rather leveled out; there actually is a short flat brook beyond. Everything below is – we’ll say it again – steep! Each of those landscapes is fundamentally different. Both are picturesque. Not surprisingly they inspired works of art. We will pick up on this next time.
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