Bayanbulak Fm
Type Locality and Naming
It was named by the Xinjiang Brigade of Regional Geological Survey in 1966 and published in Regional Stratigraphical Scale of Northwest China, the Xinjiang Uygur Zizhiqu in 1981. The type section is located at east of Goluntanggushi, northeast of Bayanbulak in Hejing County, Xinjiang. Coordinate: 84°05′00″E, 43°06′15″N.
Synonym: （巴音布鲁克组）, Bayinburuk Fm
Lithology and Thickness
Lower part, 935 m in thickness, consists of grey green and grey massive tuffaceous sandstone, layered tuff, arkosic greywacke and phyllitic siltstone intercalated with limestone and andesitic porphyrite. Upper part, 1564 m in thickness, is composed of grey green and grey violet massive andesitic tuff, fined andesitic breccia, andesitic porphyrite and amygdaloidal andesitic porphyrite, with oolitic limestone at the top.
Relationships and Distribution
Lower contact
The lower and upper boundaries of the formation yet remain unclear. Regionally, the next older unit is the Talebulak Fm of mid-Silurian
Upper contact
The lower and upper boundaries of the formation yet remain unclear.
Regional extent
The formation is merely restricted in Narat Mt. area, northeast of Bayanbluk in Hejing County in the Middle Tianshan Mts. region.
GeoJSON
Fossils
The oolitic limestone yields trilobite Encrinurus, Corals Heliolites densitabulatus, Thamnopora, Mesofavosites khalfini, Favosites gothlandicus, Squameofavosites, Yacutipora, Dictyofavosites rarus.
Age
Depositional setting
Additional Information