Needmore Formation

Needmore Formation Stratigraphic range: Devonian
Type	sedimentary
Underlies	Marcellus Shale and Millboro Shale
Overlies	Oriskany Formation
Lithology
Primary	shale
Location
Region	Appalachian Mountains
Country	United States
Extent	Pennsylvania and West Virginia
Type section
Named for	Needmore, Pennsylvania
Named by	Willard and Cleaves, 1939

The Devonian Needmore Formation or Needmore Shale is a mapped bedrock unit in Pennsylvania, Maryland, Virginia, and West Virginia.

The Needmore Formation was originally described by Willard and Cleaves in 1939 as a dark- to medium-gray limy shale, based on exposures in southern Fulton County, Pennsylvania. They considered it part of the Onondaga Group.

DeWitt and Colton (1964) described the Needmore as "soft calcareous medium dark-brownish-gray and greenish-gray shale and mudrock...and soft, slightly calcareous very fissile brownish-black shale" that is not resistant to weathering. They estimated its thickness in their study area as approximately 150 feet.

DeWitt and Colton (1964) identified brachiopods (Coelospira acutiplicata, Eodevonaria arcuata), trilobites (Phacops cristata), and ostracods (Favulella favulosa) in the Needmore.

Type locality is between Needmore and Warfordsburg in southern Fulton County, Pennsylvania.

Relative age dating places the Needmore in the middle Devonian.

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