Bashibulake Fm
Type Locality and Naming
Kashi-Yarkand region (NW Tarim). The naming section is located in the vicinity of Bashibulake (Baxbulak) in the piedmont zone of the Tianshan Mountains, Xinjiang. Named by the Xinjiang Petroleum Administration in 1975.
Synonym: Baxbulak Fm
Lithology and Thickness
Littoral-lacustrine clastic rocks: Lower part is brown mudstone with grayish green mudstone, muddy siltstone and sandy coquina. Upper part is alternating beds of brown mudstone and sandy mudstone on the one hand and fine sandstone and pebbly sandstone on the other. The thickness is ~210–280 m.
Relationships and Distribution
Lower contact
This formation has a conformable contact with the underlying Eocene Zhuoyoulegansu Fm.
Upper contact
Disconformable or unconformable contact with the overlying Keziluoyi Fm.
Regional extent
This formation mainly occurs in the area from the seat of Wuqia County to Wulukeqiati in the piedmont zone of the Tianshan Mountains west of Kashi and eastward it extends to east of Kumuhaimugou and the piedmont zone of the West Kunlun Mountains west of the Yengisar-Shache-Pishan line.
GeoJSON
Fossils
The bivalves include Ostrea tianshanensis, O. cf. plicata, Anomia sp., Aralocardia sp., Nucula ferganensis and Crassatella sp. and the foraminifera are represented by Spiroplectammina, Cibicides, Cibicidoides, Baggina, Heterolepa, etc.
Age
Depositional setting
Additional Information