Index map
Alternating beds of hard and soft Paleozoic sedimentary rocks, folded like the wrinkles in a kicked floor rug, are the hallmark of the Appalachian Valley and Ridge Province. Extending some 900 miles (1500 km) from New York to Alabama, and flanked by flat-lying sedimentary strata to the west and Precambrian metamorphic rocks to the east, this famous belt of parallel structures reflects the several great continental collisions that formed the Appalachian chain and the Pangaea supercontinent some 300 to 400 million years ago. |
