Sunjiawan Formation

The Sunjiawan Formation (simplified Chinese: 孙家湾组; traditional Chinese: 孫家灣組; pinyin: Sūnjiāwān Zǔ) is a geological formation in Liaoning, China, with strata possibly dating back to the early Late Cretaceous, specifically the Cenomanian.^[1] Dinosaur remains are among the fossils that have been recovered from the formation.^[2] It forms part of the same geological sequence as the older and underlying Yixian Formation and Jiufotang Formation. It primarily consists of variegated conglomerates with rare intercalations of thin bedded sandstones, siltstones and mudstones.^[3]

Sunjiawan Formation
Stratigraphic range: Early Cenomanian ~99–95 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Type	Geological formation
Overlies	Unconformity with Fuxin Formation
Lithology
Primary	Conglomerate
Other	Sandstone, siltstone, mudstone
Location
Coordinates	41.7°N 120.8°E / 41.7; 120.8
Approximate paleocoordinates	46.2°N 112.1°E / 46.2; 112.1
Region	Liaoning
Country	China
Extent	Beipiao Basin
Sunjiawan Formation (China) Show map of China Sunjiawan Formation (Liaoning) Show map of Liaoning

Dinosaurs

Remains of the following dinosaurs have been found in the formation:

Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon		Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited.

Dinosaurs

Ankylosaurs

Ankylosaurs of the Sunjiawan Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Crichtonpelta[4]	C. benxiensis			A partial skeleton.	A ankylosaurine ankylosaurid
Crichtonsaurus	C. bohlini			A partial skeleton.	A ankylosaurine ankylosaurid

Ornithopods

Ornithopods of the Sunjiawan Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Hadrosauroidea Indet.	Indeterminate
Shuangmiaosaurus	S. gilmorei			A partial left upper jaw and lower jaw.	A styracosternan ornithopod

Sauropods

Sauropods of the Sunjiawan Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Borealosaurus	B. wimani				A titanosaurian sauropod
Titanosauriformes Indet.	Indeterminate

Theropods

Theropods of the Sunjiawan Formation
Genus	Species	Location	Stratigraphic position	Material	Notes	Images
Tyrannosauroidea Indet.	Indeterminate

See also

• List of dinosaur-bearing rock formations
• Zhumapu Formation