title: Bloyd Formation
text: # Bloyd Formation
  
  The Bloyd Formation, or Bloyd Shale, is a geologic formation in Arkansas. It preserves fossils dating back to the Carboniferous period.
  
  ## Stratigraphy
  
  The Bloyd Formation conformably overlies the Hale Formation and unconformably underlies the Atoka Formation. Five formal and one informal members are recognized in the Bloyd Formation (in stratigraphic order):
  
  * Kessler Limestone Member
  * Dye Shale Member
  * Parthenon Sandstone Member (also known as the "middle Bloyd sandstone")
  * Woolsey Member
  * Baldwin coal (an informal unit at the top of the Woolsey Member)
  * Brentwood Limestone Member
  
  In the eastern parts of the Ozarks in Arkansas, the Bloyd Formation becomes undifferentiated with the underlying Hale Formation and is called the Witts Springs Formation.
  
  ## Paleontology
  
  ### Flora
  
  * Archaeolithophyllum
  
      A. missouiense
  * Cuneiphycus
  
      C. aliquantulus
  * Donezella
  * Eflugelia
  * Girvanella
  
      G. minuta
  * Paraepimastopora
  * Stachedoides
  
      S. spissa
  
  ### Ostracods
  
  * Amphissites
  
      A. confluens
      A. nodosus
      A. rothi
  * Bairdiolites
  * Hollinella
  
      H. bassleri
  * Kegelites
  * Kirkbya
  
      K. bendensis
      K. jolliffana
  * Pseudoparaparchites
  
  ### Sponges
  
  * Haplistion
  
      H. sphaericum
  * Steioderma
  
      S. hadra
  * Virgaspongia
  
      V. ichnata
  
  ### Trace Fossils
  
  * Conostichus
  
      C. arkansanus
  
  ### Incertae sedis
  
  * Asphaltina
  
      A. cordillerensis
  * Clacisphaera
  
      C. laevis
  * Nostocites
  * Osagia
  * Proninella
  
      P. strigosa
  