Devonian Mahantango Formation is a mapped bedrock unit in Pennsylvania, West Virginia, and Maryland. It is named for the North branch of the Mahantango Creek...

shales near the middle of the Mahantango Formation are classified by geologists as slope-formers. Marcellus and Mahantango shale beds dipping at 60° to...

shale with some sandstone. There are two main formations encompassed by the group: the Mahantango Formation and the Marcellus Shale. In southwestern Virginia...

The Rhinestreet Shale is a geologic formation in the Appalachian Basin. It dates back to the Devonian period. The Rhinestreet is an organic or Black Shale...

stream is on rock of the Mahantango Formation, the Harrell Formation, the Irish Valley Member, and the Trimmers Rock Formation. A number of roads cross...

Pennsylvania Mahantango Creek (Snyder County), a tributary of the Susquehanna River in Snyder and Juniata counties, in Pennsylvania Mahantango Formation, a mapped...

The Monongahela Formation is a geologic formation in West Virginia, Pennsylvania, Ohio, and Maryland. It is dated to the Carboniferous period. The top...

Givetian Tully Formation Mahantango Formation Olentangy Shale (lower) Plum Brook Shale Prout Limestone Silica Formation Eifelian Amherstburg Dolomite Columbus...

the Portage Group. The West Falls formation is bounded above by the Java Formation and below by the Sonyea Formation. It comprises the Angola Shale and...

The Knox Supergroup, also known as the Knox Group and the Knox Formation, is a widespread geologic group in the Southeastern United States. The age is...

The Whitewater Formation is a geologic formation in Ohio and Indiana. It preserves fossils dating back to the Ordovician period. The Whitewater was first...

The Laurel Formation, also known as the Laurel Limestone or the Laurel Dolomite, is a geologic formation in Indiana and Kentucky. It preserves fossils...

The Tully Formation is a geologic unit in the Appalachian Basin. The Tully was deposited as a carbonate rich mud, in a shallow sea at the end of the Middle...

The Mississippian Pocono Formation is a mapped bedrock unit in Pennsylvania, Maryland, and West Virginia, in the United States. It is also known as the...

Commons has media related to Fort Payne Formation. The Fort Payne Formation, or Fort Payne Chert, is a geologic formation found in the southeastern region of...

The Ordovician Martinsburg Formation (Om) is a mapped bedrock unit in Pennsylvania, New Jersey, Maryland, Virginia, and West Virginia. It is named for...

include the Catskill Formation, the Marcellus Shale, the Helderburg Formation, the Mahantango Formation, the Oriskany Formation, the Marine Beds, and...

The Waynesville Formation is a geologic formation in Ohio and Indiana. It preserves fossils from the Late Ordovician period. Earth sciences portal Indiana...

Givetian Tully Formation Mahantango Formation Olentangy Shale (lower) Plum Brook Shale Prout Limestone Silica Formation Eifelian Amherstburg Dolomite Columbus...

The Kope Formation is one of the three component bedrock formations of the Maquoketa Group that primarily consists of shale (75%) with some limestone (25%)...

The Point Pleasant Formation is a geologic formation in Ohio. It dates back to the Middle Ordovician. Earth sciences portal Ohio portal Paleontology portal...

this group which is the only ammonoid found in the Hamilton Group (Mahantango Formation) in Pennsylvania and New York. Devonian of Algeria, Canada (Northwest...

Bertie Limestone, also referred to as the Bertie Dolomite and the Bertie Formation, is an upper Silurian (Pridoli, or Cayugan) geologic group and Lagerstätte...

The Queenston Formation is a geological formation of Upper Ordovician age (Maysvillian to Richmondian Stage), which outcrops in Ontario, Canada (along...

composed of the Marcellus Shale and the Mahantango Formation. The Ridgeley Member of the Old Port Formation, another sandstone and conglomerate, forms...

The Logan Formation is the name given to a Lower Carboniferous (early Osagean) siltstone, sandstone and conglomeratic unit exposed in east-central Ohio...

in the Tully Formation and Marcellus Formation in New York and Pennsylvania, including the Windom shale there. The Mahantango Formation in Pennsylvania...

Enrolled Eldredgeops rana from an outcrop of the Middle Devonian Mahantango Formation near Milesburg, Pennsylvania, with schizochroal eye visible...

The Grant Lake Formation is a geologic formation in Ohio and Kentucky. It preserves fossils dating back to the Ordovician period. Earth sciences portal...

Helderberg Mountains. The upper portion of the Helderberg, or the Kalkberg Formation is host to the Bald Hill ash bed, dated to 417.6 million years ago. The...