Xiadiyag Fm
Type Locality and Naming
The type section lies from Diyag to Gyiseng, northwest of Zanda County, Tibet. It was named by Guo Tieying et al. in 1991.
Synonym: "lower" Diyag Fm (which is the meaning of "Xia" "Diyag")
Lithology and Thickness
Limestone. Dominated by crystalline limestone, intercalated with minor quartz sandstone and black slate. Thickness >500 m.
Relationships and Distribution
Lower contact
Conformable contact with the Devonian stratum (Musi Gr)
Upper contact
Conformable contact with the overlying Shangdiya Fm (which means the “upper” Diyag Fm),
Regional extent
Mainly distributed along Gyiseng to Diyag of Mayang, Zanda County, and scattered from Mama to Lungmu Co of the Karakorum subprovince.
GeoJSON
Fossils
Brachiopods are represented by Syringothyris sp., with also Fusella sp., Pseudosyrinx cf. mylkensis, etc. At Keshimier, Conodonts Clydognathus qilwernensis, Polygnathus communis, Bispathodus stabilis, etc. of the uppermost Tournaisian have been collected from the bottom of the Syringothyris limestone, and its Upper part contains Visean Coral Caninophyllum archiaci (Gupta, V. J., 1973; Guo Tieying et al., 1991).
Age
Depositional setting
It is interpreted as normal neritic deposits.
Additional Information