Regolith production rate represents a fundamental parameter governing regolith evolutionary dynamics. Recent validation of U-series disequilibrium chronometry has established its robust capacity to constrain regolith formation timescales, enabling its extensive application to quantifying weathering materials production rates. To elucidate the applicability of U-series disequilibrium in granitic weathering profiles under low-temperature and atmospheric precipitation-dominated conditions, we investigated a 250 cm-thick granite weathering profile on the ridge top of the Dunhua Basin, located approximately 260 km southeast of Changchun, Jilin Province, China. We systematically analyzed U-series isotopic signatures and mineralogical composition of profile samples, and determined production rates via numerical simulation of the U-series disequilibrium model. For numerical modeling, the entire profile was vertically subdivided into three stratified subzones, yielding depth-resolved production rates of 1.72 ±0.18, 81 ±23, and 1.38 ±0.08 m/Ma from top to bottom, respectively. Our results reveal distinct depth-dependent variability in regolith formation and evolution, which is predominantly controlled by freeze-thaw cycling processes. Comparative analysis of regolith production and denudation rates further demonstrates that the studied profile maintains a non-steady state evolutionary condition. This study verifies the essential theoretical prerequisite of parameter-stable subzones division for reliable U-series disequilibrium dating, and reveals a non-monotonic depth trend of regolith production rates characterized by an initial increase and subsequent decrease with increasing depth. This depth-dependent humped attenuation pattern provides robust geochemical evidence for the mechanistic evolution of granite regolith systems. Our findings advance the mechanistic understanding of weathering dynamics and landscape evolution across global granitic terrains.
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