Wulagen Fm
Type Locality and Naming
Kashi-Yarkand region (NW Tarim). The naming section is located on the south limb of the Wulagen (Ulagun) syncline in Wuqia County in the piedmont zone of the Tianshan Mountains, Xinjiang. Named by the Xinjiang Petroleum Administration in 1975.
Synonym: Ulagun Fm
Lithology and Thickness
In the piedmont zone of the Tianshan Mountains west of Kashi, the lithology is relatively uniform. Except in individual sections where red mudstone and gypsum beds are present, most sections consist dominantly of grayish green mudstone and calcareous sandstone with thin-bedded limestone. In the piedmont zone in the southeastern part of the southwest Tarim subbasin, the lithology is highly varied and turns into the alternating beds of red mudstone and conglomerate with grayish green bands in some sections. The thickness is ~20–120 m.
Relationships and Distribution
Lower contact
The formation has a conformable contact with the underlying Eocene Kalataer Fm.
Upper contact
The formation has a conformable contact with the overlying Eocene Bashibulake Fm (Baxbulak Fm).
Regional extent
This formation is distributed from the national border eastward roughly to east of Hotan.
GeoJSON
Fossils
There occur the foraminifera Anomalina, Cibicides, Nonion, Rotalia, etc., the ostracods Cytherella, Loxoconcha, etc., the bivalves Sokolovia bohmi, Ostrea (Flemigostrea) kaschgarica and Liostrea kokanensis and the gastropods Turritella, Athleta, etc. The above-mentioned fossils are essentially the commonest genera and species in the Eocene Turkistan Formation in the Fergana and Tajik basins, former Soviet Union, of which the mollusk fossils are mostly the endemic species in Central Asia. Furthermore, some forms are also found in the mid-upper Eocene of France, Poland and Ukraine.
Age
Depositional setting
It is interpreted as neritic or lagoonal deposits.
Additional Information