Needmore Shale
The Devonian Needmore Formation or Needmore Shale is a mapped bedrock unit in Pennsylvania, Maryland, Virginia, and West Virginia.
01Description
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 (southern Bedford County, Pennsylvania, and most of Allegany County, Maryland) as approximately 150 feet.
Fossils
DeWitt and Colton (1964) identified brachiopods (Coelospira acutiplicata, Eodevonaria arcuata), trilobites (Viaphacops cristata), and ostracods (Favulella favulosa) in the Needmore.
Notable Exposures
Type locality is between Needmore and Warfordsburg in southern Fulton County, Pennsylvania.
02Age
Relative age dating places the Needmore in the middle Devonian.
Sources and credits
This article is adapted from the Wikipedia article “Needmore Shale”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.
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