Catskill Escarpment - Natural History

Natural History

The Escarpment owes its formation to three phases in different geological epochs. Two different processes shaped the range into what it is today.

Its limestone bedrock began forming 400 mya, during the Silurian period, when the Catskill region was a river delta and the shallow sea it drained into. The river carried eroded material from the Taconic Mountains to the northeast, then reaching as high as 15,000 feet (4,600 m) over present-day sea level. Later, during the Acadian orogeny, the sea became the deeper Appalachian Basin, and the sand and clay from the newer mountains became the shale and sandstone found throughout the Catskills today.

Eventually the sea floor itself began to drain and uplift. The area of today's Escarpment and northeastern Catskills had been the river's distributaries and had the thickest layer of Devonian sediments, leading it to uplift as a whole and become a plateau rather than fracturing into mountains. Gradually, the upper levels of the plateau began to erode and create stream basins, eventually becoming today's mountains and valleys

The Escarpment of that time was more gradually sloped than it is now, with much loose rock from its uplift. Sometime between 100,000 and 300,000 years ago, the Illinoian glaciation swept through the region. This had two impacts on the Escarpment. Not only did it scour and steepen its slopes, leaving the many bare cliffs found today, it carved out both Platte and Kaaterskill cloves from the narrower, shorter and shallower valleys of smaller streams. In the latter, the gouge in the Escarpment was so deep it resulted in stream capture, as the outflow streams from North-South Lake, the headwaters of what would eventually be named Schoharie Creek instead flowed down into the new gorge. This both created Kaaterskill Falls, one of the Catskills' early tourist attractions, and relocated the source of the Schoharie to its present location.

As the Escarpment began to revegetate in the wake of the retreat of the Wisconsin glaciation, its forests remained exposed to weather due to their location. Lightning in particular caused many forest fires. Catskill forest historian Michael Kudish believes that the southern Escarpment "has been burned over many times, perhaps hundred of times, during the last several thousand years".