The Sinuiju Formation(신의주층) is a geologic formation in North Korea. Formerly of uncertain age, it is now thought to be Early Cretaceous. A variety of fossils are known from the formation, including those of anurognathid pterosaurs (possibly Jeholopterus) and birds such as the specimen of a very large enantiornithine with a 5 cm long tibia and a 3.5 cm long pygostyle. Frogs have also been found in the formation. Numerous compression fossils of insects have also been found.

Fossil content

Fish Amphibians Pterosaurs Birds Dinosaurs Dinosauria indet (tooth) Mammals Multituberculata indet. Insects Other invertebrates