Original paper

Late Pleistocene restructuring of the river network on the Great Hungarian Plain: evidence from the Tiszasas section

Novothny, Ágnes; Gábris, Gyula; Tsukamoto, Sumiko; Thamó-Bozsó, Edit; Techmer, Astrid; Frechen, Manfred

Abstract

A fluvial sand succession was excavated at Tiszasas section, close to the present course of the River Tisza (Pannonian Basin). It was possible to distinguish lithologically between sediments of two different palaeorivers within the sediment record by means of heavy mineral analysis. In order to obtain age constraints for the re-arrangement of the drainage pattern in this area, luminescence dating was carried out on ten samples. The post-Infrared Optically Stimulated Luminescence (post-IR OSL) and pulsed OSL protocols were applied to obtain the equivalent dose (De) of the quartz samples, as they were contaminated by feldspar. Additionally, the K-feldspar separates were measured using a post-IR Infrared Stimulated Luminescence (pIRIR) protocol. Most of the OSL ages (ranging between 10.4 ± 1.1 ka and 17.8 ± 1.1 ka) and pIRIR ages (ranging between 10.4 ± 0.6 ka and 15.2 ± 1.0 ka) are in agreement within uncertainty, suggesting that both quartz and feldspar had been well bleached before burial. Relatively continuous sedimentation occurred at Tiszasas from the end of Late Pleniglacial (c. 26.5–15 ka) to the Lateglacial period (c. 13.5–11.7 ka). When the Danube had abandoned this area, very likely a so-called "Third River" occupied the present course of the Tisza River during the end of Late Pleniglacial carrying sediments from the Northern Carpathians. During Lateglacial the palaeoriver network has significantly changed due to the subsidence of the western and northern margins of the Great Hungarian Plain; the Tisza and Körös rivers occupied their present channel in this area.

Keywords

hungarypirirpost-ir oslquaternarysandpalaeoriver