Flame Extinguished! End-Triassic Mass Extinction Polycyclic Aromatic Hydrocarbons Reflect More Than Fire

Summary Widespread biomass burning events during the end-Triassic mass extinction are supported by combustion-derived polycyclic aromatic hydrocarbons (PAHs) from European and Greenland sections. However, our investigation into a range of PAHs from focal end-Triassic extinction outcrops in the southwest UK reveals otherwise. We find major discrepancies in combustion-derived PAHs that support ETE biomass burning events were more localised. In addition, we find evidence of soil erosion during the newly proposed marine expression of the end-Triassic extinction and no evidence of biomass burning. Finally, below the extinction horizon good correlation between increases in combustion-derived PAHs and low molecular weight S- and O-containing PAHs associated with the terrestrial realm suggest that increased continental run off could account for changes in pyrogenic PAHs given their degraded but pyrogenic source.