The palynological assemblages from the J-K boundary beds of the Bureya Basin, Russian Far East

Palynological assemblages were studied from the coal-bearing Upper Jurassic (Talanja Formation) to the Lower Cretaceous (Dublikan Formation) deposits of the Bureya Basin, Russia. The palynological assemblages from the upper part of the Talanja Formation are dominated by gymnosperms, mainly Ginkgocycadophytus (up to 40%) and conifers related to Pinaceae (up to 70%). The contribution of non-seed plants is not great, but their diversity is considerable. The miospore assemblages of the Talanja sequence are characterized by the last appearance of the spore taxa Staplinisporites pocockii, Camptotriletes cerebriformis, Camptotriletes nitida, and Cingulatisporites sanguinolentus. The palynological assemblage from the Dublikan Formation is dominated by ferns (up to 84%), represented mainly by Cyathidites and Duplexisporites. Among gymnosperms the role of Classopollis increases (making up about 20%). Another feature is the first appearance of the spore taxa Stereisporites bujargiensis, Neoraistrickia rotundiformis, Contignisporites dorsostriatus, Appendicisporites tricostatus, and Concavissimisporites asper.