Kalaker Fm
Type Locality and Naming
SW Tarim Basin. The Kalaker Fm was named by Ma Shipeng, Wang Yuzhen et al. in 1981. The type locality is in Tieklik Mountain, south of Yecheng County, Xinjiang Weiwuerzhu Zizhiqu (Xinjiang Uygur Autonomous Region).
Synonym: （卡拉克尔组）
Lithology and Thickness
The Kalaker Fm is composed of low-grade metamorphosed carbonate rock and clastic rock, subdivided into two parts. Lower part is termed "variegated slate member" composed of grey-black, dark-grey, greyish and purple red thin- to thick-bedded marl and cryptocrystalline limestone >104 m thick. A slate of 10 m thick lies on the top of the member, the slate in the topmost horizon bears microplants. Upper part is termed "quartzitoid sandstone member" composed of grey medium-thick-bedded quartz sandstone over 100 m thick with a general fining-upward grain size. A slate of 10-20 m thick appears in the base of the formation, bearing Trachysphaeridium. The total thickness of the formation is 280 m.
Relationships and Distribution
Lower contact
It is in unconformable contact with underlying Heluositan Gr
Upper contact
It is disconformably overlain by the Layilek Fm
Regional extent
SW Tarim Basin.
GeoJSON
Fossils
Microplant: Margominuscula sp., Trachysphaeridium sp., etc.
Age
Depositional setting
Additional Information
The age of the formation was determined on the basis of microplant characteristics, the similar paleomagnetic pole position of the formation (59.1°N, 313. 1°) to that of Changzhougou Fm in Jixian (68°N, 340°) (Li Yong'an, 1984), and the obvious unconformity in lower part (which was termed "Congling Movement").