Geologicheskii Vestnik

The distribution of individual and average figurative data points of terrigenous rocks (sandstones and shales) of the Mashak Formation at the base of the Middle Riphean of the Southern Urals is considered, based on most of the currently widely used discriminant diagrams for the reconstruction of paleogeodynamic settings of sedimentary formations. It is shown that the information obtained with their help cannot be considered as 100 % correct. This is true for both early and mid-1980s charts, doubts about the validity of which have been expressed in the last 10–15 years by many experts, and for the recently proposed new diagrams, the authors of which believed that they were able to get rid of the shortcomings inherent in the works of their predecessors.

terrigenous rocks, Mashak Formation, South Urals, paleogeodynamic discriminant diagrams

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