Издатель: Nanjing University Press , Место издания: Nanjing , Год издания: 1994

Morphological and taxonomic analysis of graptolites assemblages from the Cambrian and Ordovician boundary deposits is performed. Systematic composition of the Upper Cambrian - Lower Ordovician is suggested for the Siberian Platform. The Lower Ordovician (the Lower Tremadoc) in Salair, the Lower and Upper Tremadoc in Gorny Altai, and the Upper Cambrian in Kuznetsk Alatau are characterized by graptolites. It is concluded that to solve the problem of determination of a boundary between Cambrian and Ordovician in Siberia, additional complex researches on trilobites, conodonts, and graptolites are necessary. The particular type of Late Cambrian facies in Siberia is characterized by assemblages with Siberiograptidae. The stratigraphic importance of the Tremadoc Siberian graptolites is highlighted by occurence of Rhabdinopora in the Lower Tremadoc and of Bryograptus, Anisograptus, Adelograptus and Kiaerograptus in the Upper Tremadoc.