Tieyingzi Fm

The type section is located in the West Hills of the Tieyingzi, Guangxingyuan Country, Keshiketeng Banner of Inner Mongolia, and the reference section is situated to the northeast of the Tieyingzi area. It was named by the 2^nd Regional Geological Survey Party of Liaoning Province in 1971.

Sandstone and Volcaniclastics. Composed mainly of purple coarse-clastic rocks intercalated with slate and acidic tuff. Lower part consists of interbeds of yellow-green conglomerate, sandy conglomerate, fine conglomerate and acidic tuff, intercalated with slate, being possessed of basal conglomerate, yielding plant fossils (phytolites), with a thickness of 513 m. Middle part of the formation is composed dark-grey and grey-purple polymictic sandstone or sandy conglomerate, conglomerate and tuffaceous sandstone, intercalated with siltstone, with a thickness of 224 m. Upper part of the formation is composed dark-grey and purple silty slates, intercalated with polymictic sandstone, siltstone and metamorphosed tuff, yielding plant fossils (phytolites), with a thickness of 709 m. Total thickness is over 1446 m.

Yields such plant fossils (phytolites) as Gigantonoclea, Comia, Pecopteris, Asterophyllites, Cordaites, Taeniopteris and Sphenophyllum, representing the Late Permian