Abandoned channels are essential in the Quaternary floodplains, and their infill contains different paleoenvironment recorders. Grain-size distribution (GSD) is one proxy that helps characterize the alluviation and associated sedimentological processes of the abandoned channels. The classic statistical methods of the grain-size analysis provide insufficient information on the whole distribution; this necessitates a more comprehensive approach. Grain-size endmember modeling (EMM) is one approach beyond the traditional procedures that helps unmix the GSDs. This study describes the changes in the depositional process by unmixing the GSDs of a Holocene abandoned channel through parameterized EMM integrated with lithofacies, age–depth model, loss-on-ignition (LOI), and magnetic susceptibility (MS). This approach effectively enabled the quantification and characterization of up to four endmembers (EM1-4); the characteristics of grain-size endmembers imply changes in sedimentary environments since 8000 BP. EM1 is mainly clay and very fine silt, representing the fine component of the distribution corresponding to the background of quiet water sedimentation of the lacustrine phase. EM2 and EM3 are the intermediate components representing the distal overbank deposits of the flood. EM4 is dominated by coarse silt and very fine sand, representing deposition of overbank flow during the flood periods. This paper demonstrates that the parametrized grain-size EMM is reasonable in characterizing abandoned channel infill sedimentary depositional and sedimentation history.
The loess-paleosol profile near the settlement of Pécel has a notable size among the loess-paleosol sequences of the Northern Carpathian territories. Therefore, comprehensive sedimentological examinations were performed to understand the profile and the information preserved in it. The past periodicity and intensity of winds were showed by particle composition studies (GSI, U-ratio). At least two source areas can be presumed based on geochemical indices (CIA, CIW, Rb/Sr, Zr/Rb). Based on the characteristics of the chemical composition of sulphide minerals (P, S, Pb, Ni, As sulphides), the lower 10 m of the profile was supposed to be transported from the NW direction (Buda Thermal Karst, Börzsöny, Cserhát). Sufficient information is not yet available in order to determine the source area of the upper 10 m. By using the mentioned indexes, major developing and weathering horizons also could be identified.
Kurgans are the custodians of outstanding archaeological, natural and environmental-historical value in the lowland landscape of Eastern Europe, which has been continuously transformed over millennia by agricultural activity. Their protection and study are, therefore, essential. By comparative soil and sedimentological analysis of the soil levels buried during the kurgans’ construction, the levels of buried soil, and the recent surface soil, we can gain information on the environmental changes of the second half of the Holocene; we can also gain information about how the activity of humans, even in the case of prehistoric cultures, can cause changes in the soil and environment on a local scale, beyond the regional scale. The aim of our research was to conduct a geoarchaeological examination of the Császárné Mound, which is one of the kurgans in the Hungarian Great Plain. For this purpose, sedimentological analyses (grain size distribution, magnetic susceptibility measurements), a pollen analysis, and a malacological analysis were carried out on the samples from the Császárné Mound. The complex geoarchaeological investigation of the mound allowed us to distinguish three different construction layers in the kurgan’s soil material. Besides the archaeological results, we were able to reconstruct steppe-like environmental conditions before and during construction in the local surroundings of the kurgan.
Numerous loess/paleosol sequences (LPS) in the Carpathian Basin span the period of Marine Isotope Stage (MIS) 2 and the last glacial maximum (LGM). Nevertheless, only two known records—Madaras and Dunaszekcső—preserve highly resolved records with absolute chronologies with minimal uncertainties, which enable the meaningful assessment of feedbacks and short-term climatic fluctuations over this period. The Madaras profile is located at the northern margin fringe of the Bácska loess plateau; Dunaszekcső, located on the Danube to its west, yields a chronology built on over 100 14C dates yet spans only part of MIS 2, missing half of the LGM including its peak. Here, we add to the previously published 14C chronology for Madaras (15 dates) with an additional 17 14C and luminescence ages. Resulting age models built solely on quartz OSL and feldspar pIRIRSL data underestimate the 14C based chronology, which is likely based on inaccuracies related to luminescence signal behavior; we observe age underestimations associated with unusual quartz behavior and significant signal loss, a phenomenon also observed in Serbian and Romanian loess, which may relate to non-sensitized grains from proximal sources. Our new chronology provides higher resolution than hitherto possible, yielding consistent 2 sigma uncertainties of ~150–200 years throughout the entire sequence. Our study indicates that the addition of further dates may not increase the chronological precision significantly. Additionally, the new age model is suitable for tackling centennial-scale changes. The mean sedimentation rate based on our new age-depth model (10.78 ± 2.34 years/cm) is the highest yet recorded in the Carpathian Basin for MIS 2. The resolution of our age model is higher than that for the Greenland NGRIP ice core record. The referred horizons in our profile are all characterized by a drop in accumulation and a higher sand input, the latter most likely deriving from nearby re-exposed sand dunes.