Geologicheskii Vestnik

Object of study – Zilmerdak Formation of the Upper Riphean Karatau Group at the intersection of the Zilmerdak ridge with the Ufa – Inzer – Beloretsk highway, where a virtually continuous section of the suite in the stratotype locality was exposed in natural outcrops and road cuttings, which made it possible to give the most complete idea of the composition, structure and thickness of its deposits. Materials of a detailed description of this section are published for the first time. In the Zilmerdak Formation, no objects have yet been found for a reliable determination of the age of its deposits. The available U-Pb datings (LA-ICP-MS) of detrital zircons from sandstones of the Zilmerdak Formation have led some researchers to the conclusion that it is necessary to change the stratigraphic position of the basal Biryan subformation for the Zilmerdak Formation and assign it to the Vendian Asha Group. There are no grounds for revising the stratigraphic position of the Biryan Subformation of the Zilmerdak Formation in the given section and other outcrops of the formation based on geological, lithological and mineralogical data.

http://doi.org/10.31084/2619-0087/2025-3-1

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