Deposits of the Artinskian Stage in the Middle Urals have been studied in the basins of the Yuryuzan, Ufa, Sylva, Kosva, and Usva rivers.

The distribution of brachiopods in the sediments of the Artinskian Stage of the Urals has been repeatedly considered in the literature by F. N. Chernyshev [1889, 1902], G. N. Fredericks [1918], B. V. Miloradovich [1949], and D. L. Stepanov [1939, 1951]. However, all researchers did not divide the Artinskian Stage into horizons based on brachiopods, although the abundance and diversity of Artinskian brachiopods have long suggested the possibility of using them to distinguish two substages and even local horizons of the Artinskian Stage [Stepanov, 1939, Miloradovich, 1949, 1951]. In addition, the so-called Sylva reefs occupy a controversial stratigraphic position, which M. V. Kulikov [1948], V. D. Nalivkin [1949], and D. L. Stepanov [1951] attributed to the uppermost part of the Artinskian Stage, adjacent to the Kungurian; B. V. Miloradovich [1949] determined their age as Kungurian.

For many years, the stratigraphic scheme of the Permian deposits of the Urals has been based on the scheme of D. M. Rauser Chernousova [1940]. It was developed in accordance with the distribution of individual foraminifera assemblages along the section. Many of the horizons identified by D. M. Rauser Chernousova have retained their names and have been adopted in the Unified Scheme of Permian deposits of the Urals of 1962, and their sections are considered stratotypic.

In 1963, the study of reference sections of the Lower Permian of the Western Urals provided an opportunity to study in detail complete, well exposed, faunistically richly characterized sections of the Shvagerian horizon of the Asselian Stage. Until then, complete sections of the Shvagerian horizon were not known on the western slope of the Middle Urals ...