New insights into the timing of the Yellow River flowing into the North China Plain: Evidence from detrital zircon UPb geochronology and heavy mineral assemblages of sediments

Identifying the timing of the Yellow River flowing into the North China Plain (also referred to as the integration of the middle and lower reaches of the Yellow River or the integration of the Yellow River) is essential for understanding the evolutionary processes of the Yellow River and the North China Plain, as well as the interplay between tectonic deformations and climatic change in this region. This study investigated sediments from borehole S005, drilled in the Yellow River alluvial fan within the Kaifeng sag, Henan Province, using detailed magnetostratigraphic analysis, detrital zircon UPb geochronology, and heavy mineral assemblage analysis. The magnetostratigraphic and optically stimulated luminescence results reveal that sediments in borehole S005 span about 3.33 Ma. Of these sediments, those deposited after about 1.32 Ma exhibit similar detrital zircon UPb age spectra and heavy mineral assemblages to the sediments in the middle and upper reaches of the Yellow River, suggesting that the Yellow River has cut through the Sanmen Gorge and supplied sediments to the North China Plain since about 1.32 Ma. This study excludes the far-field effect of the Late Pliocene uplift of the northeastern Qinghai-Tibet Plateau on the integration of the Yellow River. Additionally, this study proposes that the integration of the Yellow River was triggered by the fluvial incision and headwater erosion associated with the drastic climatic change during the Pleistocene.