Á. Novothny–B. Kiss–T. Sági–B. Bradák–Eric A. Oches–W. D. McCoy–Ch. Thiel–G. Surányi–T. Végh–J. Szeberényi–D. Csonka–G. Barta–D. Kaufman–Th. Ntaflos–E. Horváth: Luminescence dating of loess-paleosol sequences containing the Bag Tephra from the N-Carpathia
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szeptember 24.
2021
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Horváth Erzsébet
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Two tephra horizons have been used in the Hungarian loess stratigraphy as marker horizons to support the correlation between different loess-paleosol sequences. The older one is called 'Bag Tephra' described at thirteen locations in the Carpathian Basin. The 'Bag Tephra' has been correlated to the Villa Senni Tuff (Colli Albani) with an age of 351 ka. Although Sági et al. (2008) proposed that both the origin and the integrity of 'Bag Tephra' is questionable, the layer is still usually referred to as a strong marker horizon in the Carpathian Basin.
Five loess successions, Basaharc, Hévízgyörk, Galgahévíz, Pásztó and Isaszeg were dated and geochemically and petrographically reinvestigated. Luminescence dating (pIRIR-290) and amino acid racemization (AAR) were applied to obtain age constraints for the deposition and formation of loess and paleosol at each location.
Luminescence and AAR results are in agreement at Basaharc, but some discrepancy was found at Hévízgyörk. The Bag Tephra horizon can be divided into two groups (Basaharc and Isaszeg, called Isaszeg Tephra – Pásztó and Hévízgyörk, called Pásztó Tephra) by petrographic properties of the investigated tephras. The pIRIR-290 minimum ages and the luminescence properties of the investigated samples support the petrological results. Petrographical and chronological differences imply that the eruption centres and/or the eruption times were different which produced the two types of tephra.
