Rincon Valley Formation
| Rincon Valley Formation | |
|---|---|
| Stratigraphic range: | |
| Type | Formation | 
| Unit of | Santa Fe Group (geology) | 
| Underlies | Camp Rice Formation | 
| Overlies | Hayner Ranch Formation | 
| Thickness | 610 meters (2,000 ft) | 
| Lithology | |
| Primary | Sandstone, mudstone, conglomerate | 
| Other | Gypsum | 
| Location | |
| Coordinates | 32°35′19″N 106°58′02″W / 32.588750°N 106.967225°W | 
| Region | New Mexico | 
| Country | United States | 
| Type section | |
| Named for | Rincon Valley | 
| Named by | Seager et al. | 
| Year defined | 1971 | 
The Rincon Valley Formation is a geologic formation found in the Rincon Valley of New Mexico. It preserves fossils dating back to the Miocene epoch and records a time when the valley was a closed basin, just before being integrated into the ancestral Rio Grande River.