Wanghudun Fm

The naming section is located in an area from Wanghudun to Doumu ~8 km southwest of Qianshan County, Anhui. Named by the No. 311 Geological Party, Anhui Bureau of Geology, in 1971 and formally published in the paper “The Paleocene containing mammal fossils in Anhui” written by Qiu Zhanxiang et al. in 1977.

Mainly purplish red and brownish red sandstone. The lithology varies greatly laterally; from the basin margin to center the lithology changes markedly from coarse to fine and the thickness increases progressively. The formation is divided into two parts: Lower part is alternating beds of purplish red conglomerate, pebbly muddy sandstone and sandstone; Upper part is purplish red or brownish red sandstone and muddy sandstone with grayish white sandstone, being the main fossil-bearing member of the formation. The thickness is ~800 to 1500 m.

The Wanghudun Formation is now one of the very important early Paleocene horizons in Asia and up to now at least more than 20 kinds of fossil have been found. The main forms include the lizards Qianshanosaurus huangpuensis and Agama sinensis and the mammals Huaiyangale chianshanensis, Eosigale gujingensis, Qipania yui, Anictops tabiepedis, Paranictops majuscula, Heomys sp., Mimotona wana, Zeuctherium niteles, Harpyodus euros, Pappictidops orientalis and Altilambda tenuis. In addition, fossil mammals such as Altilambda pactus have also been found at Mao’an in Huaining County.

The Wanghudun fauna is characterized by the appearance of abundant special Asian groups such as Pseudictopidae and Anagalida, which predominate in the fossil assemblage. This seems to indicate that in the early Paleocene the vast Asian continent east of the Turgay Strait and north of the ancient Mediterranean Sea (Himalayan Sea) was an isolated or insulated region that essentially had no direct passageway to connect with the European and North American continents.

The formation is dominated by fluvial deposits.