Daodi Fm
Type Locality and Naming
Nihewan Basin. The type section is located at the Laowo Gully (E114°39′, N40°08′), about 750 m north of Daodi village, Nanxinzhuang town, Yangyuan County, Hebei Province (Cai et al., 2013 in Wang et al., 2013). It was formally named by Du et al. (1988).
Synonyms: Zhang et al. (2003) regarded this formation as a junior synonym of the Yuxian Fm proposed by Wang (1982). Pang (2003) suggested that this formation is a junior synonym of the Shixia Fm named by Huang and Guo (1981). Cai et al. (2013, in Wang et al., 2013) restricted the Daodi Fm to layer 3~9 of the Laowogou section (Cai, 1987; Du et al., 1988), and regarded that it is a synonym of the Yuxian Fm but didn’t decide the priority of these two formations.
Lithology and Thickness
The Daodi Fm is characterized by a series of fluvio-palustrine grey and greyish-green silty clays and light-yellow fine sands, silts, and gravels. It contains mammalian, sporopollen, ostracod, bivalve, gastropod, fish, and reptile fossils. Its thickness is about 30 m.
Relationships and Distribution
Lower contact
In the type section, the Daodi Fm disconformably contacts with the underlying Upper Pliocene Shixia Fm (red clay) (=Huliuhe Fm).
Upper contact
In the type section, the Daodi Fm disconformably contacts with the overlying Lower to Middle Pleistocene Nihewan Fm.
Regional extent
The formation is restrictedly distributed to both downstream sides of the Huliu River in the Nihewan Basin, Hebei Province.
GeoJSON
Fossils
Mammals: Sorex sp., Paenelimnoecus chinensis, Ochotona sp., Sinocricetus progressus, Nannocricetus mongolicus, Ungaromys spp., Mimomys sp., Mimomys sp. 2., Mesosiphneus praetingi, Pliosiphneus sp. 2, Pseudomeriones complicidens, Dipus fraudator, Paralactaga anderssoni, Micromys tedfordi, Apodemus zhangwagouensis, Chardinomys yusheensis, C. nihowanicus, ?Karnimata sp., Saidomys sp. . (Cai, 1987; Li et al., 2008) Ostracoda: Candona, Candoniella. Sporopollens: Pinuspollenites sp..
Age
Depositional setting
It is interpreted as a river, lake, or swamp environment.
Additional Information