Pittsburgh coal seam

The Upper Pennsylvanian Pittsburgh coal bed of the Monongahela Group is extensive and continuous, extending over 11,000 mi2 through 53 counties.

1) Pennsylvanian sediments were deposited on an aggrading and prograding coastal plain within a foreland basin adjacent to the Alleghanian fold and thrust belt.

[12] The Pittsburgh coal bed formed during a hiatus in active clastic deposition that allowed for the development of a huge peat mire.

Significant parts of the clay layer immediately below the Pittsburgh coal rest on an unconformity, that is, an old eroded surface.

The underlying erosion surface is considered the top of the Conemaugh Group, formerly known as the Lower barren measures because this formation contains few coal seams.

The coal was poured into trenches dug into the hillside, rolled to the edge of the river, and transported by canoe and boats to the military garrison.

Sometime around 1765, a fire broke out in this mine, which continued to burn for years, leading to collapse of part of the face of the hill.

Mining rights were formally purchased from the chiefs of the Six Nations in 1768, and from this point on, coal fueled the explosive growth of industry in the Pittsburgh Region.

During the early nineteenth century, entrepreneurs in western Pennsylvania adapted British coke-making practices to produce coke for local iron works.

The mining of Pittsburgh-seam coal boomed off after 1860 as the rapidly expanding iron and steel industry adopted coke.

During the 1900s and 1910s, mine companies exploited the Lower Connellsville district of the Pittsburgh seam, adding greatly to total output.

Pittsburgh-seam output continued to fall after a World War II surge as steel mills adopted alternative fuels such as natural gas and oil and improved the energy efficiency of iron furnaces.

Much of the remaining resource to the south of Marion County, W. Va., and west through much of Ohio is high in ash and sulfur, and is not likely to be extensively mined in the near future given current economic trends.

[26] The Big Vein was discovered in 1804, in an outcrop east of Frostburg, Maryland,[27] but it was not until 1824 that small-scale shipment to Georgetown began.

Coal was hauled overland to Cumberland, Maryland and then loaded onto flatboats for shipment down the Potomac River during the spring floods.