| Horse Spring Formation | |
|---|---|
| Stratigraphic range: Neogene | |
Horse Spring Formation with stromatolite fossils | |
| Type | Sedimentary |
| Sub-units | Lovell Wash member, Bitter Ridge Limestone, Thumb member, Rainbow Gardens member |
| Underlies | Muddy Creek Formation |
| Lithology | |
| Primary | conglomerate, sandstone, and limestone |
| Location | |
| Region | Nevada |
| Country | United States |

The Horse Spring Formation is a geologic formation in Nevada. It preserves fossils dating back to the Neogene period. The lower unit is conglomerate and the middle and upper are sandstone and freshwater limestone.
{{Cite Q}}: Missing first/last names in Wikidata for Becky W. Purkey, Ernest M. Duebendorfer {{Cite Q}}: Missing first/last names in Wikidata for Frank DeCourten