Climate and Tectonic Forcing of Depositional Evolution in the Southern North China Basin Since ∼3 Ma

Abstract Marginal basins provide sensitive yet incomplete records of climate and tectonic forcing, and the southern North China Basin provides an ideal setting to decode these interactions since the late Pliocene. A 135.6‐m borehole sequence, the XiaoQian (XQ) core, recovered from the Fuyang region, was dated using AMS 14 C, OSL, and ESR, supplemented by magnetostratigraphic correlations to the parallel WLB core. Integrated analyses of physical and geochemical proxies were then employed to reconstruct the depositional evolution over the past ∼3 million years. The succession records three main stages. Stage I (∼3–1.6 Ma) comprises sandy delta‐front deposits, indicating active progradation into a lacustrine basin. Stage II (∼1.6–0.128 Ma) consists of rhythmically bedded silty clays, recording hydrological instability on a delta plain. Stage III (∼0.128 Ma to present) is dominated by floodplain muds, reflecting low‐energy alluviation under stable tectonic conditions. Variations in sediment continuity and thickness reflect the combined influence of tectonic segmentation and autogenic reworking, which modulated the completeness of the stratigraphic record. Within well‐preserved intervals, elemental and magnetic proxies show coherent trends that parallel regional and global reference curves, indicating that monsoon hydroclimate and base‐level fluctuations were the primary external controls, while local tectonic setting and depositional dynamics influenced how these environmental signals were recorded.