Graptolite biozones of the Bohemian Lower and Middle Ordovician and their historical development

Abstrakt

An overview on graptolite zones in the Prague Basin is done. As the rests of graptolites are preserved nearly exclusively in the clayey shale facies of the Klabava, Šárka and Dobrotivá Formations, a reasonable graptolite zonation is establish only in thee.

Revised biostratigraphical scheme is proposed for this part of the Bohemian Ordovician. Only two zones are distinguished inside the Šárka Formation.