Tahtakair Fm
Type Locality and Naming
Along the Tahtakair Plateau, Tahtakair District, South Ustyurt. V.V. Kurbatov, V.N. Polyakov in 1996. The borehole at the West Shakhpakhty area is taken as the stratotype, as recommended by the Samarkand meeting (383) as a type section for the previously distinguished Lower Tonashin subformation of the Tonashin Fm. Used in the legend of the Priaral (Pre-Aral) subseries of sheets of geological maps of the 1:200000 scale, 1998. On the Yu. Ustyurt, it was distinguished as the Lower Tonaishin subsv. of the Tonaishin sv. (91; 383, table 4, p.2). V.I. Troitsky et al. (165) call the Takhta-Kair Fm as the Kuanysh Fm, mistakenly believing that it was already published under this name.
Synonym: Tahtakair Suite, Тахтакаирская св., Takhtakir, Takhtakair ?
Lithology and Thickness
Coarse white-gray sandstones with layers of black clayey-silty (aleuritic) rocks with carbonaceous detritus. Thickness 120-418m.
Relationships and Distribution
Lower contact
Lies with erosion on the Paleozoic or Ergozin Fm.
Upper contact
With apparent conformity, it is overlain by the Aalenian - Early Bajocian Berdak Fm.
Regional extent
Boreholes of the Southern Ustyurt. On the Yu. Ustyurt and in the Takhta-Kair region. Tahtakair Fm is included in the Gurud Horizon (252) and is a facies analogue of the Lower subsv. of the Gurud Fm. Corresponds to VII, VIII and IX productive mountains.
GeoJSON
Fossils
In Well No.1, West Shakhpahty (interval 2583.6-2586.3 m) contains complexes of spores and pollen - Classopollis (188), ginkgo and coniferous. Spores are represented by Middle Jurassic Cyathidites minor Couper (87), Toroisporis solutionis Kr., Camptotriletes anogrammensis K.-M., Concavisporites microverrucosus Couper.
Age
Depositional setting
Additional Information