Jiulaopo Fm
Type Locality and Naming
The type section is located at the “Wujiapo section” (E109°18′, N34°11′), south side of the Ba River, and east of Wujiapo village, Xiehu town, Lantian County, Shaanxi Province (BGMRS(Shaanxi)P, 1998). It is derived from the “Lantian Fm” erected by Liu et al. (1960). Because the “Lantian Fm” has already been occupied by the Proterozoic Sinian Lantian Fm in Xiuning County, Anhui Province (Li, 1936), so Zheng et al. (1999) proposed the “Jiulaopo Fm” being the substitute of Liu et al.’s “Lantian Fm”.
Lithology and Thickness
It mainly consists of purplish-red and brownish-red claystones rich in calcareous nodules, and sandy claystones. Its lower part contains interlayers of brownish-grey gravels or conglomerates. It lower part contains fossil mammals and sporopollens. Its thickness is in range of 25~62 m.
Relationships and Distribution
Lower contact
In the type section, the Jiulaopo Fm unconformably contacts with the underlying Upper Miocene Bahe Fm. In other areas, this formation unconformably contacts with the Bailuyuan Fm (Oligocene) or the Honghe Fm (late Eocene).
Upper contact
In the type section, the Jiulaopo Fm unconformably underlies the Quaternary Sanmen Fm. Regionally, it unconformably overlain by the Pliocene Youhe Fm.
Regional extent
This formation is distributed to Lantian-Weinan area, Shaanxi Province.
GeoJSON
Fossils
Mammals: Viverridae gen. et sp. indet., Felidae gen. et sp. indet., Hyaenictitherium wongi, Ictitherium viverrinum, Adcrocuta eximia, Hipparion cf. H. hippidiodus, Hipparion spp., Chilotherium habereri, Acerorhinus paleosinense, Chleuastochoerus stehlini, Microstonyx indet., Cervavitus novorossiae, Cervavitus indet., Procapreolus latifrons, Schansitherium cf. S. tafelli, Gazella sp., cf. Tragoreas sp., Prosiphneus licenti, Typhlomys sp. (Zhang et al., 2002)
Age
Depositional setting
Its lower part is interpreted as river-lake environment, whereas its upper part is possibly deposited in dust environment.
Additional Information