The Allegheny Plateau , in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

, is a large

dissected plateau A dissected plateau is a plateau area that has been severely eroded such that the relief is sharp. Such an area may be referred to as mountainous, but dissected plateaus are distinguishable from orogenic mountain belts by the lack of folding, me ...

area of the

Appalachian Mountains The Appalachian Mountains, often called the Appalachians, (french: Appalaches), are a system of mountains in eastern to northeastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period. They ...

in western and central New York, northern and western

Pennsylvania Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...

, northern and western

West Virginia West Virginia is a state in the Appalachian, Mid-Atlantic and Southeastern regions of the United States.The Census Bureau and the Association of American Geographers classify West Virginia as part of the Southern United States while the Bur ...

, and eastern

Ohio Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The sta ...

. It is divided into the

unglaciated Allegheny Plateau The Unglaciated Allegheny Plateau is located in an arc around southeastern Ohio, West Virginia, into western Pennsylvania and a small portion of southwestern New York State. This area is a dissected plateau, characterized by sandstone, shale, an ...

and the

glaciated Allegheny Plateau The Glaciated Allegheny Plateau is that portion of the Allegheny Plateau that lies within the area covered by the last glaciation. As a result, this area of the Allegheny Plateau has lower relief and gentler slopes than the relatively rugged Ung ...

. The plateau extends southward into western

, eastern

Kentucky Kentucky ( , ), officially the Commonwealth of Kentucky, is a state in the Southeastern region of the United States and one of the states of the Upper South. It borders Illinois, Indiana, and Ohio to the north; West Virginia and Virginia to ...

and

Tennessee Tennessee ( , ), officially the State of Tennessee, is a landlocked state in the Southeastern region of the United States. Tennessee is the 36th-largest by area and the 15th-most populous of the 50 states. It is bordered by Kentucky to th ...

where it is instead called the

Cumberland Plateau The Cumberland Plateau is the southern part of the Appalachian Plateau in the Appalachian Mountains of the United States. It includes much of eastern Kentucky and Tennessee, and portions of northern Alabama and northwest Georgia. The terms "Alle ...

. The plateau terminates in the east at the

Allegheny Mountains The Allegheny Mountain Range (; also spelled Alleghany or Allegany), informally the Alleghenies, is part of the vast Appalachian Mountain Range of the Eastern United States and Canada and posed a significant barrier to land travel in less devel ...

, which are the highest ridges just west of the

Allegheny Front The Allegheny Front is the major southeast- or east-facing escarpment in the Allegheny Mountains in southern Pennsylvania, western Maryland, eastern West Virginia, and western Virginia, USA. The Allegheny Front forms the boundary between the ...

. 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 the

Ohio River The Ohio River is a long river in the United States. It is located at the boundary of the Midwestern and Southern United States, flowing southwesterly from western Pennsylvania to its mouth on the Mississippi River at the southern tip of Illino ...

, and the

Bluegrass region The Bluegrass region is a geographic region in the U.S. state of Kentucky. It makes up the central and northern part of the state, roughly bounded by the cities of Frankfort, Paris, Richmond and Stanford. The Bluegrass region is characteriz ...

in the south, generally south of the Ohio 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 . By the Allegheny Front, however, elevations may reach well over , with relief of up to .

Geology and physiography

The Allegheny Plateau is a physiographic section of the larger

Appalachian Plateau The Appalachian Plateau is a series of rugged dissected plateaus located on the western side of the Appalachian Mountains. The Appalachian Mountains are a mountain range that run down the Eastern United States. The Appalachian Plateau is the nor ...

province, which in turn is part of the larger Appalachian physiographic division.

References

Bibliography

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External links

Photographs of the Allegheny Plateau and the Allegheny River watershed region
* {{Authority control Plateaus of the United States Northeastern United States Appalachian Mountains Appalachian Ohio Geography of Appalachia Physiographic sections Physiographic regions of the United States

Geology and physiography

See also

References

Bibliography

External links