Needmore Shale


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

Description

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 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.

Fossils

DeWitt and Colton identified brachiopods, trilobites, and ostracods in the Needmore.

Notable Exposures

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

Age

Relative age dating places the Needmore in the middle Devonian.