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MAR comparisons between different chronometric methods for two profilesin the Bodrogkeresztúr area

Makó László, Molnár Dávid, Cseh Péter, Sümegi Pál

Studia Quaternaria

2021

Vol. 38, Nr 1

67--73

The deepening and exploration of the loess-palaeosol section at the foot of the Kopasz Hill at Bodrogkeresztúr have been carried out to expand the existing knowledge of the Carpathian foothill palaeoenvironmental factors and their impact. The study deals with particle size analysis, organic matter and carbonate content. For the presentation of age-depth models, the OSL dates of Bodrogkeresztúr (BKT) and the 14C dates of Bodrogkeresztúr, brickyard 1 were used-, and the diagrams of the Accumulation Rates (AR) derived from them. These were compared with Mass Accumulation Rate (MAR) calculations based on OSL and 14C data from BKT and 14C data from Bodrogkeresztúr, brickyard 1. It became evident that there is a significant difference between the two sections, which may be due to the upland position, the overlap, or the wind tunnel effect. Sedimentological studies revealed coarser grain composition, however, the nearly complete absence of coarser sand fraction is also noticeable in the case of BKT. Also, the entire section is characterized by increased carbonate content due to post-sedimentation processes, recarbonization and leaching. The AR and MAR results show the difference between the suitability of different chronometric methods, indicating that the top of both sections may have been redeposited or eroded.

Estimation of the durations of breaks in deposition – Speleothem case study

Pawlak J., Hercman H., Sierpień P., Pruner P., Gąsiorowski M., Mihevc A., Zupan Hajna N., Bosák P., Błaszczyk M., Wach B.

Geochronometria

2020

Vol. 47, no.1

154--170

Speleothems provide one of the most continuous terrestrial archives. However, due to changing conditions in temperature/humidity or the chemistry of percolating water, sedimentation breaks (hiatuses) and erosional events are possible and are commonly recorded in speleothems. Sedimentation breaks with durations longer than the resolution of the studied record should be considered in potential speleothem age-depth models. The most classic and reliable solution to the problem is the independent construction of age-depth models for the parts of speleothems separated by the hiatuses. However, in some cases, it is not possible to obtain a sufficient number of dating results for reliable age-depth model estimation. In such cases, the problem can be solved by the application of other sources of chronological information. Here, based on a few speleothem examples, an alternative approach – oxygen isotopic stratigraphy – is used to estimate the chronology for the parts of speleothems where there is not enough chronological information for classic age-depth models. As a result, the deposition break duration can be estimated.

Revisiting the Palaeolithic site at Szeged-Öthalom: attempt for appoint the Palaeolithic horizon

Molnár Dávid, Makó László, Sümegi Pál, Sümegi Balázs P., Törőcsik Tünde

Studia Quaternaria

2019

Vol. 36, Nr 1

45--53

This paper presents a new approach to study the palaeoecological and archaeological benefits of the previously investigated Szeged-Öthalom area. The aim was to combine the archaeological results with the palaeoecological ones by a new integral view. Age-depth models of 14C dated charcoal were calculated via Bayesian method to reconstruct the sediment accumulation rates in the investigated loess- palaeosol sequences. Moreover, the age of a Mammoth bone found in 1935 at the nearby Palaeolithic site was correlated with the calculated accumulation rates. Through our new results, the age of the Palaeolithic site could be correlated to the late LGM dust-accumulation-peak period. Even if this period is considered as cold and dry, the palaeoecological settings indicated dense forest cover and cool climate in the investigated area. This means that the palaeoenvironment may have encouraged the diffusion of Gravettian hunters in this area, founding campsites like Öthalom in the southern part of the Carpathian Basin.