Abstract: Previous studies have documented remarkable changes in the carbon cycle during the Early Triassic. To verify these trends and improve our understanding of carbon cycling during the Early-Middle Triassic, we investigate the new δ¹³C_carb record for the Early-Middle Triassic in the Tianshengqiao section of South China. Our study shows that the δ¹³C_carb values in the Tianshengqiao section have received minimal diagenetic alterations. The δ¹³C_carb profile initially shows a negative excursion of 2.2‰ within the Member I of the Jialingjiang Formation, followed by a positive excursion of 3.8‰ in the lower part of the Member III of the Jialingjiang Formation. After that, δ¹³C_carb displays a negative excursion of 2.5‰ in the Member III of the Jialingjiang Formation, followed by a positive excursion with a maximum of +5.0‰ at the base of the Member I of the Guanling Formation. Above the maximum value, the δ¹³C_carb profile exhibits a third negative excursion and then recovers and stabilizes around +1‰ to +2‰ through the Member II of the Guanling Formation to the Yangliujing Formation. The observed trend of the δ¹³C_carb profile in the Tianshengqiao section can be correlated with the global C-isotopic excursions derived from the coeval sections worldwide. The similarity of the Early-Middle Triassic δ¹³C_carb profile to those from other sections worldwide is indicative of the near completeness of the stratigraphic interval of the Tianshengqiao section. Our results suggest that the δ¹³C_carb profile in the Tianshengqiao section represents a global carbon cycle perturbation. The stratigraphic coincidence between the carbon cycle perturbation and the limited biotic recovery has been documented in the Tianshengqiao section, suggesting that the physical mechanism of the carbon cycle perturbation may have contributed to the prolonged biotic recovery.

Key words: chemostratigraphic correlation, carbon cycle perturbation, prolonged biotic recovery, Early-Middle Triassic