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Two sections of marine carbonate strata, Podu and Lengshuixi, from the Yangtze platform, South China, are investigated in terms of major geological events and carbon-strontium isotope responses. The results show a large-scale regression and a Large Igneous Province (LIP) event occurred in succession in the short interval of the late Guadalupian, inducing a biodiversity crisis. The regression event, marked by an increase in the 87Sr/86Sr ratio, is observed in the Jinogondolella postserrata Zone. It contributed significantly to the reduction in species habitat, leading to notable losses within the shallow-water species assemblage. A subsequent LIP event occurred after the appearance of Jinogondolella altudaensis, releasing CO2 and numerous other deleterious gases that further amplified the crisis in shallow-water to deep-sea environments. The corresponding decline in Sr and C isotopes could have been a response to the basaltic eruption (relative increase from mantle-derived Sr) and release of 12C-enriched CO2. During the process of creation of the LIP, the decline in δ13Ccarb was mainly associated with 12C-enriched CO2 release from organic matter in sedimentary strata, and high-temperature isotope fractionation during the volcanic eruption stage (exceeding 1200 °C). This study could further provide valuable clues regarding the development process of the major geological events and the causes of the biodiversity crisis. [ABSTRACT FROM AUTHOR]