Upper Proterozoic strata of metamorphic rocks on the right bank of the Erzin River, west of its right tributary (Ular River), A.V. Ilyin and V.M. Moralev subdivided into two series: lower - terrigenous and upper - carbonate. Two formations are distinguished in each of them: the Teschemian and Mugurian, Balaktykkhemian and Chartisian. A brief description of the section (from bottom to top) is as follows...