Donguz Formation
The Donguz Formation, Donguz Svita, or Donguz Rocks () is a Middle Triassic geological formation that crops out on the right bank of Donguz River in Orenburg Oblast, Russia, across the settlement of Pervomaisky. The formation is equivalent to a biostratigraphic unit, the Donguz Gorizont. It is famous for its rich collection of the fossils of Middle Triassic tetrapods. It is a nature monument (особо охраняемых природных территорий (ООПТ)). Fossil content. The following fossils have been found in the Donguz Formation: