Increased Early Permian Chemical Weathering in North China Did Not Contribute to Global Warming

The Late Paleozoic Ice Age represents the geological period in the Phanerozoic that is most comparable to the modern climate environment. Reconstructing its climatic evolution mechanisms, particularly the process of deglaciation during the Early Permian, is of great scientific value for understanding the regulatory mechanisms of the Earth's carbon cycle and the patterns of contemporary climate change. Reduced continental weathering during the Early Permian has been proposed as a potential mechanism contributing to Early Permian warming. However, this proposal remains under debate due to lack of support from geological data. In this study, we conducted a comprehensive comparative analysis of chemical weathering intensity in North China using both CIA (Chemical Index of Alteration) and clay mineral data that collected by our own group and from previous publications. By integrating age data and sedimentation rates, we made preliminary estimates of chemical weathering fluxes during the Early Permian. The results indicate that in North China, despite climatic drying associated with the northward drift of the North China Block, chemical weathering flux did not decrease but instead showed a slight increase across the Sakmarian–Artinskian transition. Therefore, we proposed that chemical weathering, at least in North China, may have not been a contributor to Early Permian warming. Whether the same goes with other regions requires more detailed study when more data are made available.