Reconstruction of tectonically driven Quaternary fluvial dynamics of the Western Kura Fold-Thrust Belt (Eastern Caucasus, Georgia)

Since the Plio-Pleistocene, southward migration of shortening in the Eastern part of the Greater Caucasus (GC) into the Kura foreland basin has formed the Kura fold–thrust belt (KFTB) and Alazani piggyback basin between the GC and KFTB, modifying the drainage network within the southern foreland. The northern, eastern and south-eastern flanks of the Western KFTB (Gombori range) expose the predominantly alluvial Alazani series, while the central (highest) part of the range is covered by Tsivi suite. The base of the Alazani series is estimated to be 2.7-2.5 Ma and deposition spanned the Akchagyl and Apsheronian regional stages. The KFTB likely initiated during the Akchagyl-Apsheronian period, and thus the paleocurrents of the alluvial Alazani series sediments represent potential archives for tracking resulting drainage reorganization within the foreland. Previous measurements of paleocurrents from the Alazani series revealed a reversal from south to north flow directions, but the measurements were limited to the northern flank of the Gombori range. Here we present new observations from the central and southern flanks of the Gombori. Results from the eastern and southeastern regions are consistent with the currents from the northern flank, but paleocurrents from the Tsivi suite are more complex and raises additional questions regarding its depositional context and age. The new results help to build a more complete picture of fluvial dynamics driven by Quaternary tectonic deformations within the GC foreland.