Dating of the stepped quaternary fluvial terrace system of the Yellow River by electron spin resonance (ESR)

Abstract

Abstract Since the 1980's, the improvement of the electron spin resonance (ESR) geochronological method and its application to the dating of bleached quartz extracted from sediments currently permit to provide geochronological data on Pleistocene fluvial deposits. In the present study, we have applied this method on sediments carried out from the Yellow River terrace system in the sector of Zhongwei (Ningxia province, China). This alluvial system is composed of a set of stepped fluvial deposit remnants (T1 to T9) from the actual floodplain (T1) up to 160 m of relative height. The ESR ages obtained in this work, by placing the installation of the river terrace system in the Middle and Upper Pleistocene (between 712 and 60ka), give information in relation to the causes of the succession of terraces. The results show that the construction of the system seems not only linked to a continuous regional tectonic uplift in the Middle Pleistocene but that the succession of incisions also seems controlled by Quaternary climatic cycles.