Jollytown coal
Hundred sandstone
Upper Marietta
Washington “A” coal
Middle Washington
Lower Washington
Lower Marietta
Washington (No. 12) coal
Little Washington coal
Mannington sandstone
Waynesburg “A” coal
Waynesburg Sandstone
Elm Grove limestone
The Washington Formation is a coal, sandstone, and limestone geologic formation located in Ohio, Pennsylvania and West Virginia.[1] It dates back to the Lower Permianperiod, with its base at or near the Permian/Carboniferous boundary.[2][3] The Washington formation and the Dunkard Group as a whole was deposited at a time when the continents were in the process of forming the "Super Continent" Pangaea as well as a gradual drop in sea levels.[4] The result during this period was coals being thinner and impure with high ash content. The limestones found with in the formation are exclusively freshwater deposits.
Paleofauna
The paleofauna of the Washington Formation is considered similar to that of the Texas Red Beds, sharing many fish and tetrapod taxa. Some of the taxa listed suggest an Artinskian age.[5] Lucas et al 2013 discusses the fauna of the formation.[5]
Upper Warren, Lower Warren, Speechely Stray, Speechely, Balltown A, Balltown B, Balltown C, Sheffield, First Bradford, Second Bradford, Third Bradford, Kane