Washington Formation | |
---|---|
Stratigraphic range: Permian | |
![]() Bituminous coal (Washington Coal, Upper Pennsylvanian; Ohio) | |
Type | Formation |
Unit of | Dunkard Group [1] |
Sub-units | Upper Washington Jollytown coal Contents |
Underlies | Greene Formation |
Overlies | Waynesburg Formation |
Lithology | |
Primary | limestone, sandstone, coal |
Other | shale |
Location | |
Region | Ohio and West Virginia |
Country | United States |
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 Permian period, 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.
The Paleo fauna of the Washington formation is considered similar to that of the Texas red beds, sharing many taxa of fish and tetrapods with the red beds. Some of the taxa listed suggest an Artinskian age [5]
Orthacanthus
Xenacanthus
Ectosteorhachis
Dipnoa
Eryops
Trimerorhacis
Zatrachys
Diploceraspis
Acheloma
Edaphosaurus boanerges
Dimetrodon limbatus
Ophiacodon retroversus
Diadectes
{{cite journal}}
: Cite journal requires |journal=
(help); External link in |first=
(help); Missing or empty |title=
(help)CS1 maint: numeric names: authors list (link)