Erdengtu Fm
Type Locality and Naming
Central-Eastern Inner Mongolia. The type section is located at the “Ertemte section” (E114°05′, N41°52′), southeast of Erdengtu (=Ertemte) village, Huade County, central Nei Mongol. It is derived from the “Ertemte Bed” named by Andersson (1923), and formally erected by Zheng et al. (1999).
Synonym: Ertemte Fm; Gao et al. (2014a) treated the Haerebo Fm (=Harr Obo Fm) as a synonym of the Erdengtu Fm.
Lithology and Thickness
The Erdengtu Fm is characterized by a series of light grey, yellowish-brown, and reddish-yellow sandy mudstones. Its upper part is rich in calcium. It contains abundant fossil sporopollens, charophytes, gastropods, bivalves, fishes, amphibians, reptiles, and mammals. Its thickness is around 1 m.
Relationships and Distribution
Lower contact
No underlying rock unit could be seen in the type section. Regionally, the next older unit is the widespread Tongguer Fm
Upper contact
In the type section, the Erdengtu Fm disconformably contacts with the overlain Quaternary deposits.
Regional extent
The formation is restrictedly distributed to the surrounding area of the Dabsun-Nor Lake in the county of Huade, central Nei Mongol.
GeoJSON
Fossils
Mammals: “Erinaceus” mongolicus, Sorex minutoides, S. ertemteensis, S. pseudoalpinus, Zelceina kormosi, Alloblarinella sinica, Paenepetenyia zhudingi, Cokia kowalskae, Paranourosorex inexspctatus, Paenelimnoecus obtusus, Quyania chowi, Yanshuella primaeva, Chiroptera gen. et sp. indet., Alilepus annectens, Ochotona lagreli, O. minor, Pseudaplodon asiaticus, Tamias ertemtensis, Sciurus sp., Sinotamias gravis, Prospermophilus orientalis, Plioptaurista rugosa, Hylopetes auctor, Myomimus sinensis, Leptodontomys gansus, Dipoides anatolicus, Castor anderssoni, Eozapus similis, Sinozapus sp., Sicista wangi, S. ertemteensis, Lophocricetus grabaui, Paralophocricetus pusillus, Paralactaga suni, Brachyscirtetes wimani, Dipus faudator, Sinocricetus zdanskyi, Nannocricetus mongolicus, Kowalskia similis, K. neimengensis, Microtoscoptes praetermissus, Microtodon atavus, Anatolomys teilhardi, Pseudomeriones abbreviates, Prosiphneus eriksoni, Hansdebuijnia pusilla, Karnimatoides hipparionus, Apodemus orientalis, Orientalomys primitivus, Micromys chalceus, Meles suillus, Promephitis alexejevi, Hipparion sp., “Paracervulus” brevis, Honanotherium sp.. (Falhbusch et al., 1983; Storch, 1987; Qiu and Li, 2016)
Age
Depositional setting
It is interpreted as a lake environment.
Additional Information