Editing Geology of the Appalachians (section)

==== Coal, oil, and gas production ====
The Appalachian Basin is one of the most important [[coal]] producing regions in the U.S. and one of the largest in the world. [[Bituminous coal]] has been mined throughout the last three centuries. Currently, the coal primarily is used within the eastern U.S. or exported for [[Electricity generation|electrical power generation]], but some of it is suitable for [[metallurgy|metallurgical]] uses. Economically important coal beds were deposited primarily during Pennsylvanian time in a southeastward-thickening foreland basin. Coal and associated rocks form a [[Clastic rock|clastic]] wedge that thickens from north to south, from Pennsylvania into southeast West Virginia and southwestern Virginia.<ref name="coal">{{USGS|url=http://pubs.usgs.gov/pp/p1625c/CHAPTER_A/CHAPTER_A.pdf|title=Executive Summary—Coal Resource Assessment of Selected Coal Beds and Zones in the Northern and Central Appalachian Basin Coal Regions|author=Leslie F. Ruppert}}</ref>

Discovery of oil in 1859 in the [[Drake Well]], [[Venango County, Pennsylvania]], marked the beginning of the oil and gas industry in the Appalachian Basin. The discovery well opened a prolific trend of oil and gas fields, producing from upper [[Devonian]], [[Mississippian (geology)|Mississippian]], and Pennsylvanian [[sandstone]] reservoirs that extend from southern New York, across western Pennsylvania, central West Virginia, and eastern Ohio, to eastern Kentucky.<ref name="appBasin" />

A second major trend of oil and gas production in the Appalachian Basin began with the discovery in 1885 of oil and gas in lower [[Silurian]] Clinton sandstone reservoirs in [[Knox County, Ohio]]. By the late 1880s and early 1900s, the trend extended both north and south across east-central Ohio and included several counties in western New York where gas was discovered in lower Silurian Medina Group sandstones. About 1900, large oil reserves were discovered in Silurian and Devonian carbonate reservoirs in east-central Kentucky. Important gas discoveries from the lower Devonian Oriskany Sandstone in [[Guernsey County, Ohio]], in 1924; [[Schuyler County, New York]], in 1930; and [[Kanawha County, West Virginia]], in 1936 opened a major gas-producing trend across parts of New York, Pennsylvania, Maryland, Ohio, West Virginia, Kentucky, and Virginia.<ref name="appBasin" /> Another drilling boom occurred in the 1960s in [[Morrow County, Ohio]], where oil was discovered in the Upper Cambrian part of the Knox [[Dolomite (rock)|Dolomite]].<ref name="appBasin" />