Oula Gr
Type Locality and Naming
The section named by Liang et al in 1982 is located in Oula, Duoma District, Ritu County, Tibet. The reference section is located in the Jipu and Jipuria of Duoma district
Synonym: Oula Fm, Euler Gr. Prior to its designation, this formation was classified as the Doma Gr (dated from the Jurassic). Liang et al. (1982) separated the strata from the Duoma Gr and defined the age as the Early Triassic. Liang et al. (1991) renamed the Oula Gr as the Oula Fm and extended the time limit to the Early to Middle Triassic. It is considered in this lexicon that the Oula Gr, which has expanded the range of lithostratigraphy and chronostratigraphy, should not be downgraded to a Oula Fm.
Lithology and Thickness
It is dominated by dolomitic limestone interbedded with marl and contains coarse basalt and radiolarian siliceous rocks. Thickness is greater than 670 m
Relationships and Distribution
Lower contact
It conformable with the underlying Upper Permian Jipuria Fm
Upper contact
Contact relationship to the next younger unit of Rigainpunco Gr has not been observed due to faulting.
Regional extent
GeoJSON
Fossils
The fossils are mainly bivalves, and the Claraia hubeiensia-Eumorphotis inaequicostata assemblage and Schafhaeutlia liscaviensis assemblage can be formed from bottom to top. There are also gastropods and crinoids
Age
Depositional setting
Shelf plate spreading environment.
Additional Information