The Appalachian Mountains are a system of mountains in eastern North America.
Appalachia is a socially and geographically defined area in the United States roughly following the Appalachian mountains, but much wider, incorporating parts of many states. To learn more about Appalachia see
Where Is Appalachia? Lyman Stone, Medium, 1/13/2017
Dave Tabler offers this color-coded map of Appalachia. This map is important because it was made before federal funds were promised for financial aid in that region.
Once federal money was offered, many local politicians lobbied to get their areas labeled as part of Appalachia. This led to the expanded yellow borders, which most historians don’t consider to be part of Appalachia.
The pink boundaries from 1962 are considered the heart of Appalachia.
The Appalachian mountains from Newfoundland and Labrador, Canada in the north down to Alabama, USA in the south.
The highest peak in the range is Mount Mitchell, North Carolina (also the highest peak in mainland eastern North America.) 6,684 feet (2,037 m) above sea level.
They were formed roughly 480 million years ago during the Ordovician period.
They once reached elevations similar to those of the Alps and the Rocky Mountains. Since then they have experienced natural erosion.
Definitions vary on the precise boundaries. The United States Geological Survey (USGS) defines the Appalachian Highlands physiographic division as consisting of thirteen provinces.
However, some definitions don’t include the Adirondack Mountains, which geologically belong to the Grenville Orogeny and have a different geological history from the rest of the Appalachians.
Map of the Appalachian Mountain physiographic regions, highlighting the Great Appalachian Valley, naming the main valleys making it up and the main mountains on either side.
Compare to this map.
An article on Building the Northern Appalachian Mountains and New England.
Appalachian Trail
The AT is a marked hiking trail in the eastern United States extending between Springer Mountain in Georgia and Mount Katahdin in Maine. 2,200 miles (3,500 km) long.
Passes through Georgia, North Carolina, Tennessee, Virginia, West Virginia, Maryland, Pennsylvania, New Jersey, New York, Connecticut, Massachusetts, Vermont, New Hampshire, and Maine.
Maintained by trail clubs and partnerships. Managed by the National Park Service, US Forest Service, and the nonprofit Appalachian Trail Conservancy.
Most of the trail is in forest or wild lands, although some portions traverse towns, roads and farms.
Appalachian_Trail
Extension into Europe and Africa?
The mountains of the British Isles and Scandinavia turn out to be made of the same kind of rock, and formed in the same historical era.
Evidence shows that in the past all of these were one mountain system, torn by the moving of the tectonic plates – continental drift.
Here we compare where the separate mountain ranges are today, with how they looked when they were connected in the past.
The geographical regions of the east coast of the USA at one time were continuous with the western African coast.
As the continents were separating.
Formation of the Appalachian mountains
Here is a great resource – Geologic History of the Northeastern United States
Three events produced the Appalachians:
the Ordovician Taconic orogeny, which involved arc accretion;
the Acadian–Neoacadian orogeny, which involved north-to-south, transpressional, zippered, Late Devonian–early Mississippian collision of the Carolina superterrane in the southern central Appalachians, the Avalon and Gander superterranes in the New England Appalachians, and Silurian collision in the Maritime Appalachians and Newfoundland;
and the Alleghanian orogeny, which involved late Mississippian to Permian collision of all previously formed Appalachian crust with Gondwana to form supercontinent Pangea.
Similar mountain building events at the same time affected western and central Europe (Variscan events), eastern Europe and western Siberia (Uralian events), and southern Britain and Ireland.
Only the Caledonide (Grampian–Finnmarkian; Caledonian–Scandian) events affected the rest of Britain and the Scandinavian Caledonides.
This image is from The Appalachian Orogen, Robert D.Hatcher Jr. , Encyclopedia of Geology, 2005, Pages 72-81, and Reference Module in Earth Systems and Environmental Sciences, 2014
The Appalachian Orogen, Robert D. Hatcher
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