TheAllegheny Plateau (/ˌælɪˈɡeɪni/AL-ig-AY-nee) is a largedissected plateau area of theAppalachian Mountains in western and centralNew York, northern and westernPennsylvania, northern and westernWest Virginia, and easternOhio. It is divided into theunglaciated Allegheny Plateau and theglaciated Allegheny Plateau.

The plateau extends southward into westernWest Virginia, easternKentucky, andTennessee, where it is instead called theCumberland Plateau.

The plateau terminates in the east at theAllegheny Mountains, which are the highest ridges just west of theAllegheny Front. The Front extends from central Pennsylvania through Maryland and into eastern West Virginia.

The plateau is bordered on the west by glacial till plains in the north, generally north of theOhio River, and theBluegrass Region south of theOhio River.

Elevations vary greatly. In the glaciated Allegheny Plateau, relief may only reach one hundred feet or less. In the unglaciated Allegheny Plateau in southeastern Ohio and westernmost West Virginia, relief is typically in the range of two hundred to four hundred feet. Absolute highest elevations in this area are often in the range of 900 to 1,500 feet (270 to 460 m). By the Allegheny Front, however, elevations may reach well over 4,000 feet (1,200 m), with relief of up to 2,000 feet (610 m).

The Allegheny Plateau is aphysiographic section of the largerAppalachian Plateau province, which in turn is part of the largerAppalachian physiographic division.^[1]

• Allegheny Front, the transition escarpment from the Allegheny Plateau to the Ridge-and-Valley Appalachians
• List of subranges of the Appalachian Mountains
• Ridge-and-Valley Appalachians

• Faill, Rodger T. (June 1997)."A Geologic History of the North-Central Appalachians, Part 1: Orogenesis from the Mesoproterozoic through the Taconic Orogeny".American Journal of Science.297 (6):551–619.Bibcode:1997AmJS..297..551F.doi:10.2475/ajs.297.6.551.
• Faill, Rodger T. (September 1997)."A Geologic History of the North-Central Appalachians, Part 2: The Appalachian Basin from the Silurian through the Carboniferous".American Journal of Science.297 (7):729–761.Bibcode:1997AmJS..297..729F.doi:10.2475/ajs.297.7.729.
• Faill, Rodger T. (February 1998). "A Geologic History of the North-Central Appalachians, Part 3: The Alleghany Orogeny".American Journal of Science.298 (2):131–179.Bibcode:1998AmJS..298..131F.doi:10.2475/ajs.298.2.131.

• Photographs of the Allegheny Plateau and the Allegheny River watershed regionArchived 2017-10-02 at theWayback Machine

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