The Witts Springs Formation was proposed as a lithostratigraphic unit in north-central Arkansas to include the interval from a horizon equivalent to the base of the Prairie Grove Member, Hale Formation to the top of the Bloyd Formation, of the type Morrowan Series, northwestern Arkansas. The top of the Witts Springs Formation was regarded as being unconformably succeeded by the middle Pennsylvanian Atoka Formation. Recent investigation of this unit in its type area has shown that the presumed Atokan Sandstone is actually a unit confined to the Bloyd Formation. Thus, the type section of the Witts Springs in Searcy County, Arkansas only comprises the Prairie Grove and Brentwood interval. This determination is supported by the recovery of the conodonts Idlognatholdes sinuatus, Neognathodus symmetrlcus and Idiognathodus delicatus, and the ammonoids Arkanites, Branneroceras and Gastrioceras from a succession of calcareous units below the middle Bloyd sandstone throughout the type Witts Springs and other sections in the type region. The Witts Springs should continue to be interpreted in the sense of its original definition, although a supplementary reference section is needed for the upper Witts Springs which spans the Morrowan- Atokan boundary with removal of the Trace Creek from the Morrowan.
Eccher, Mary Ann; Murdaugh, Daniel J.; and Hawkins, Wildon D.
"Early Pennsylvanian Conodont-Ammonoid Biostratigraphy and the Witts Springs Problem, North-Central Arkansas,"
Journal of the Arkansas Academy of Science: Vol. 37
, Article 7.
Available at: https://scholarworks.uark.edu/jaas/vol37/iss1/7