| Dabeigou Formation | |
| Period: | Hauterivian |
| Age: | mid Valanginian-mid Hauterivian ~ |
| Type: | Geological formation |
| Prilithology: | Sandstone, mudstone |
| Otherlithology: | Tuffite, conglomerate, siltstone |
| Unitof: | Jehol Biota |
| Subunits: | Numbered Members |
| Underlies: | Dadianzi & Yixian Formations |
| Overlies: | Zhangjiakou Formation |
| Thickness: | Varies, in Yushuxia section 220m (720feet) |
| Coordinates: | 41.7°N 116.4°W |
| Paleocoordinates: | 43.6°N 118.5°W |
| Region: | Hebei |
The Dabeigou Formation is a palaeontological formation located in Hebei, China.[1] It dates from the mid Valanginian to Hauterivian age of the Cretaceous period, approximately 135 to 130 Ma.[2]
Fossils include the confuciusornithiform bird Eoconfuciusornis.[3] As of 2016 this is the oldest bird with a toothless beak known, but it belongs to a very ancestral avian lineage not closely related to living birds.