Erosion has caused polygonal rock faces to form in the sandstone and shale along the southern slope of Chandler Mountain at Horse Pens 40 in St. Clair County.
Polygonal Rock Faces
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Photograph by Mike Neilson
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Erosion has caused polygonal rock faces to form in the sandstone and shale along the southern slope of Chandler Mountain at Horse Pens 40 in St. Clair County.