The end-Guadalupian mass extinction has been investigated in Sichuan province, SW China . In the south of the province the platform carbonates of the Maokou Formation are overlain by the Emeishan flood basalts, a possible factor in the extinction event, and in the north of the province the formation is succeeded by shallow-marine carbonates of the Wuchiaping Formation (Late Permian). The extinction event is primarily recorded by the loss of fusulinaceans and possibly by species-level turnover amongst calcareous algae. The high-diversity, Middle Permian microfossil assemblages are last seen beneath a surface recording widespread emergence and karstification. In northern Sichuan emergence occurred early in the Capitanian Stage and the succeeding strata record restricted hypersaline deposition that preceded the deposition of a thick ash horizon, the Wangpo Bed. These mid-Capitanian arid conditions are replaced by humid conditions towards the end of the stage as indicated by the development of a widespread coal seam. In southern Sichuan only a thin development of this humid, coaly facies is seen developed atop the Maokou karstic surface and below the oldest flood basalt. The Guadalupian interval saw the development of large C isotope excursions in the carbonate record. These include a positive-then-negative swing late in the Capitanian and a newly discovered negative spike superimposed on an early Capitanian heavy interval. This spike may be a global phenomenon but the magnitude (8 ‰) may have been exaggerated by an increased contribution from light, respired C derived from soils during relative sea-level fall. A plethora of environmental factors approximately coincide with the extinction event, including regression, acidic volcanism and flood basalt volcanism making it difficult to unravel the relative significance of each.
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