| Ash Hollow Formation | |
|---|---|
| Stratigraphic range: Neogene | |
 Ash Hollow Formation in Nebraska | |
| Type | Geological formation |
| Unit of | Ogallala Group |
| Location | |
| Region |  Nebraska
 South Dakota |
| Country |  United States |
The Ash Hollow Formation of the Ogallala Group is a geological formation found in Nebraska and South Dakota. It preserves fossils dating back to the Neogene period. It was named after Ash Hollow, Nebraska and can be seen in Ash Hollow State Historical Park.[1] Ashfall Fossil Beds State Historical Park is within this formation.[2]
- ^ Robert Diffendal Jr.; Roger K. Pabian; J. R. Thomasson (1996). "Geologic History of Ash Hollow State Historical Park, Nebraska". University of Nebraska - Lincoln.
- ^ Smith, Jon J.; Turner, Elijah; Möller, Andreas; Joeckel, R. M.; Otto, Rick E. (2018-11-08). "First U-Pb zircon ages for late Miocene Ashfall Konservat-Lagerstätte and Grove Lake ashes from eastern Great Plains, USA". PLOS ONE. 13 (11): e0207103. Bibcode:2018PLoSO..1307103S. doi:10.1371/journal.pone.0207103. ISSN 1932-6203. PMC 6224108. PMID 30408086.