The Shawangunk Mountains
The Shawangunk Mountains sit at a special spot on the continent.
In Southeastern New York state, the Appalachian Mountain range follows a general pattern that continues all the way to Virginia, and to some extent down to Alabama. Driving across these mountains, you will cross bedrock in chronological order of its formation. Let's take Route 17 starting at the New Jersey border. The Ramapo Mountains in Rockland and Orange Counties, part of the Crystalline Appalachians, have extremely ancient gneiss bedrock. It was uplifted from deep in the earth's crust and now forms a resistant highlands. From the town of Monroe on through the rest of Orange County, the gneiss recedes below the surface and one encounters rolling terrain of the Great Appalachian Valley, made up of somewhat less ancient deep ocean sediments. Crossing into Sullivan County, the road ascends Shawangunk Ridge. Here, resting on top of the Great Valley's shale, is a massive amount of white conglomerate composed of quartz pebbles and sand. This strikingly bright, hard and quartz-rich rock consists of the debris shed by the Taconic Mountains, which rose east of here and eroded into the sea. West of the Shawangunk Ridge, the layers of conglomerate dip underground, and the limestone that overlays them forms a narrow flat valley transected by Route 209. Immediately west of the valley, and resting on top of the limestone, is the edge of a thick, flat sequence of sedimentary rocks from somewhat more recently in geologic time. This is the Allegheny Plateau, a continent-scale feature that that reaches hundreds of miles west to near Lake Erie, and south through Ohio, Pennsylvania, West Virginia and Kentucky.
The Shawangunk Ridge is continuous with the Kitatinny Ridge in New Jersey and Blue Mountain in Pennsylvania, going for hundereds of miles. For most of its length it's a narrow ridge about 1500 feet in elevation. However the most prominent part of the Shawangunk Mountains occurs towards the northern end of the ridge, just south of a major change in shape and direction of the whole Appalachian belt, a fulcrum point in the tectonic forces that shaped the continent. Here, near Kingston, NY the SE-NW trending ridges of the Mid-Atlantic meet the N-S trending ridges of New England. Whatever complex forces were going on here have shaped the layers of beautiful white Schawangunk conglomerate into a wonderland 7 miles wide of sheer cliffs, broad flat ledges, and high valleys holding pristine mountain lakes and waterfalls.
This is a uniquely beautiful area, not quite a mountain range, but not quite anything else either. The thin soil on top of the incredibly flat bedrock ledges is home in many places to "globally rare" dwarf pitch pine communities, which have a gnarled charm to them and a heavenly smell when the needles are baking in the sun. The cliffs here are gleaming white.
Bordering the massively horizontal Allegheny Plateau on one side and the gentle rolling terrain of the Great Valley on the other, the cliffs of the Shawangunks are calmly monumental.
In Southeastern New York state, the Appalachian Mountain range follows a general pattern that continues all the way to Virginia, and to some extent down to Alabama. Driving across these mountains, you will cross bedrock in chronological order of its formation. Let's take Route 17 starting at the New Jersey border. The Ramapo Mountains in Rockland and Orange Counties, part of the Crystalline Appalachians, have extremely ancient gneiss bedrock. It was uplifted from deep in the earth's crust and now forms a resistant highlands. From the town of Monroe on through the rest of Orange County, the gneiss recedes below the surface and one encounters rolling terrain of the Great Appalachian Valley, made up of somewhat less ancient deep ocean sediments. Crossing into Sullivan County, the road ascends Shawangunk Ridge. Here, resting on top of the Great Valley's shale, is a massive amount of white conglomerate composed of quartz pebbles and sand. This strikingly bright, hard and quartz-rich rock consists of the debris shed by the Taconic Mountains, which rose east of here and eroded into the sea. West of the Shawangunk Ridge, the layers of conglomerate dip underground, and the limestone that overlays them forms a narrow flat valley transected by Route 209. Immediately west of the valley, and resting on top of the limestone, is the edge of a thick, flat sequence of sedimentary rocks from somewhat more recently in geologic time. This is the Allegheny Plateau, a continent-scale feature that that reaches hundreds of miles west to near Lake Erie, and south through Ohio, Pennsylvania, West Virginia and Kentucky.
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| Lake Awosting. To the left is a drop of 1500 feet to the valley |
This is a uniquely beautiful area, not quite a mountain range, but not quite anything else either. The thin soil on top of the incredibly flat bedrock ledges is home in many places to "globally rare" dwarf pitch pine communities, which have a gnarled charm to them and a heavenly smell when the needles are baking in the sun. The cliffs here are gleaming white.
Bordering the massively horizontal Allegheny Plateau on one side and the gentle rolling terrain of the Great Valley on the other, the cliffs of the Shawangunks are calmly monumental.
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