Tracing the source areas of detrital zircon and K-feldspar in the Yellow River Basin

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Sedimentary provenance studies, which aim to identify the original source of sedimentary material, can offer valuable insights into transportation processes that occur within a given basin. Zircon and K-feldspar are complimentary and commonly used minerals in provenance tracing studies, given their representation of both stable and labile mineral components of different density. However, integration of detrital zircon and K-feldspar data has not been extensively explored for determining the source areas of the Yellow River Basin, which is one of the largest drainage basins in the world. In this study, published detrital zircon UPb ages (n = 4773) and K-feldspar Pb isotopic compositions (n = 902) in the Yellow River Basin have been compiled and analyzed. Multidimensional scaling and inverse Monte Carlo modeling, allow holistic source-to-sink relationships for sediments in different sections of the Yellow River Basin to be established. Results show that: (1) There is no significant provenance relationship between the sediments from the upper Yellow River and those from the middle and lower reaches. (2) Sediments in the source area of the Yellow River primarily come from northeastern regions of the Tibetan Plateau. Additionally, the Western Loess Plateau and deserts contribute to the material composition of the upper Yellow River. The Yinchuan and Hetao plains are the main areas in the upper reaches of the Yellow River where substantial sediment deposition occurs. These sediments are from the recycling of older sediments transported from the upper reaches of the Yellow River to the Yinchuan and Hetao plains in the early Quaternary. (3) The detrital material in the middle reaches of the Yellow River directly from the Western North China Craton, which also supplied the Eastern Loess Plateau. Sanmen Gorge, located in the middle reaches of the Yellow River, serves as a depocentre for the detrital material from the Jinshan Gorge of the Yellow River and the Wei River, which is a major tributary of the Yellow River. (4) Sediment in the lower reaches of the Yellow River is mostly derived from the middle reaches of the river, with minor contributions from the Qinling Shan. The composition of detrital material in the Yellow River Basin exhibits spatial variations influenced by aeolian and fluvial transport processes resulting from tectonic and climatic activities in the upper and middle Yellow River. Human activities, such as the construction of reservoirs and the flushing of water and sediment along the Sanmen Gorge, have a notable impact on the material composition of the downstream section of the middle and lower Yellow River. The construction of reservoirs alters the natural flow of the Yellow River, leading to changes in sediment transport and deposition downstream. This can result in a decrease in sediment load, which affects the material composition of the riverbed and banks. Additionally, the flushing of water and sediment through the Sanmen Gorge can further modify the sediment distribution in the downstream section of the Yellow River. The UPb ages of detrital zircon grains in the upper, middle, and lower reaches of the Yellow River exhibit broad agreement with the Pb isotope tracing results obtained from detrital K-feldspar grains, with proportional differences interpreted as relating to zircon recycling. This study provides an example of integrating multiple proxies to reconstruct the source of sediment in a large river system. The findings of this study can be used in the implementation of effective measures aimed at reducing the erosion of soil and protecting the ecology of the Yellow River Basin.