Dedication to the memory of a colleague, Doctor of Geological and Mineralogical Sciences Valentin P. Tverdokhlebov, a well-known specialist in sedimentology and palaeogeography of the Late Permian and Triassic of the Eastern Russian Plate and Southern Urals, as well as taphonomy of vertebrate localities. Valentin Petrovich is a long-time head of the geological survey party investigating the stratigraphy of continental red-coloured strata, tectonics and placement of minerals in the Orenburg region.