Criteria for the Bartonian Boundaries in Northeastern Peri-Tethyan and Tethyan Areas
The base of the Bartonian in the recent standard scale is not marked by any bioevents in successions of planktonic microfossils (planktonic foraminifera, nannoplankton). The definition of the Bartonian base and top in northeastern peri-Tethys is also hampered due to marked differences in planktonic foraminifera (PF) between the peri-Tethyan and Tethyan assemblages and the absence of larger benthic foraminifera (LBF). The correlation of peri-Tethyan and Tethyan planktonic zones for the Bartonian is possible in Armenia. Such correlation shows the diachronous position of Bartonian PF zones in the peri-Tethyan and Tethyan palaeogeographic regions. The revision of the nummulitic zonation of Armenia for this interval will need further work. However, the study of LBF from the N. perforatus and N. millecaput horizons and the N. fabianii Zone in the Vedi section has allowed the intervals of the SBZ17, SBZ18, and SBZ19 zones of Tethyan shallow benthic zonation to be distinguished, which can be correlated with planktonic foraminiferal standard zones P12? and P13–P16. The bioevents in LBF at/around the Bartonian–Priabonian boundary is considered for the Vedi section, where the gradual extinction of giant Nummulites corresponds to the gradual appearance of reticulate Nummulites and genus Spiroclypeus. The variants of the definition of the Bartonian–Priabonian boundary are discussed.
KeywordsBartonian Northeastern peri-Tethys Tethys Correlation Foraminifera
- Grigorian, S. M. (1986). Nummulites and Orbitoides of Armenian SSR (p. 216). AN ASSR, Erevan (in Russian).Google Scholar
- Krasheninnikov, V. A., Muzylöv, N. G., & Ptukhian, A. E. (1985). Stratigraphical subdivision of Paleogene deposits of Armenia by planktonic foraminifers, nannoplankton and Nummulites. (Pt.I. Reference Paleogene sections of Armenia). Voprosy Mikropaleontologii,27, 130–169. (in Russian with English abstract).Google Scholar
- Less, G., & Özcan, E. (2012). Bartonian-Priabonian larger benthic foraminiferal events in the Western Tethys. Austrian Journal of Earth Sciences,105(1), 129–140.Google Scholar
- Nikolaeva, I. A., Bugrova, E. M., Glezer, Z. I., Tabachnikova, I. P., Aleksandrova, G. N., Iakovleva, A. I., et al. (2006) The Paleogene system. In: T. N. Koren’ (Ed.) Biozonal stratigraphy of Phanerozoic in Russia (pp. 172–193). Sankt-Petersburg: VSEGEI Press (in Russian with English abstract).Google Scholar
- Serra-Kiel, J., Hottinger, L., Caus, E., Drobne, K., Ferrandez, C., Jauhri, A. K., et al. (1998). Larger foraminiferal biostratigraphy of the Tethyan Paleocene and Eocene. Bulletin de la Societé géologique de France,169, 281–299.Google Scholar