Understanding the formation and evolution of the middle reaches of the Yellow River is essential for comprehending the overall development of the modern Yellow River. However, two competing hypotheses propose that the formation of the middle Yellow River occurred either during the Neogene or the Quaternary. To resolve this ambiguity, we performed detrital zircon U-Pb geochronology (n = 275) and particle size analysis (n = 490), as part of a broader sedimentological investigation of Neogene strata within the Jinshan Canyon and Sanmenxia Basin of the middle Yellow River and contextualized these data with published paleomagnetic ages and regional tectonic and climatic data. Within the middle Jinshan Canyon, detrital sediments in the Weijiawa section at 8.1 Ma primarily originated from the adjacent Lvliang Mountains. However, the detrital sediments in the nearby Mujiawa section at 3.6 Ma are significantly influenced by the more distal northern Ordos Block suggesting longer distance fluvial connectivity. The composition of clastic materials in the Jiwangqiao section of Sanmenxia Basin to the south of the Jinshan Canyon is influenced by the Wei River and proximal Zhongtiao Mountains at 5.0 and 3.6 Ma, while it is shaped by the Yellow River in the middle reaches at 4.4 and 3.8 Ma. The observed provenance changes can be primarily attributed to enhanced recycling of Mesozoic sandstone and mudstone, driven by three key factors: (1) the northeastward expansion of the Tibetan Plateau, (2) the intensification of the East Asian summer monsoon system, and (3) inherent lithological variations within the geological formations. This reflects the complex interplay between tectonic activity, climatic forcing, and bedrock susceptibility in shaping the regional geomorphology.
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