| Huajiying Formation | |
|---|---|
| Stratigraphic range: Valanginian-Aptian | |
| Type | Geological formation |
| Unit of | Jehol Group |
| Sub-units | Guohedao Member, Nianzigou Member, Qiaotou Member, Sichakou Member |
| Underlies | Quingshila Formation |
| Overlies | Dabeigou Formation |
| Location | |
| Region | Hebei |
| Country |  China |
The Huajiying Formation is a geological formation in Hebei, People's Republic of China. Known for its fossils including feathered dinosaurs, the age of the formation is uncertain. It may represent an early portion of the Jehol Biota, dating to somewhere in the early Cretaceous or late Jurassic periods. It may correlate with the early Cretaceous Dadianzi Formation and parts of the Yixian Formation, with an age range between 140 and 122 Ma ago.[1] It contains the Qiaotou Member, sometimes treated as a distinct formation.
- ^ Wang, X., O’Connor, J.K., Zhao, B., Chiappe, L.M., Gao, C. and Cheng, X. (2010). "New species of Enantiornithes (Aves: Ornithothoraces) from the Qiaotou Formation in Northern Hebei, China." Acta Geologica Sinica, 84(2): 247-256.