40Ar/39Ar and U-Pb age correlations of the large Rupelian Rhodope Massif eruptions with airfall tuffs in SE, S and Central Europe

Numerous Eocene and Oligocene volcanic tuff layers within the Eastern, Central and Southern Europe sedimentary basins attest to extensive volcanic activity. Tephra dispersal of these tuffs covers areas of more than 1 000 000 km2, and the volume of erupted material to 1000s of cubic kilometers. The sources of the eruptions, how- ever, remain unknown. Using precise 40Ar/39Ar and U-Pb radiometric dating, we correlate some of these tuff layers to three silicic Rhodope Massif Rupelian (early Oligocene) supereruptions dated at 33.2 Ma, 32.8 Ma and 31.6 Ma and named Dazhdovnitsa, Borovitsa and Perelik. Hence, these tuff layers can now be used as regional stratigraphic isochronous marker horizons for correlating, dating and synchronizing deposits and events in geologic and paleoen- vironmental studies.