Upper Cambrian to Lower Ordovician radiolarites (alternations of ribbon-banded radiolarian cherts and siliceous shales) from Kazakhstan are dated accurately by means of conodonts. They represent the only known continuous ...
The rate of taxic turnover of nearly 400 radiolarian species/subspecies is analyzed in order to document long term biotic change of plankton during the Middle Jurassic to Early Cretaceous (Aalenian to Aptian). The pattern ...