An 80-million-year sulphur isotope record of pyrite burial over the Permian–Triassic

Despite the extensive use of sulphur isotope ratios (δ 34 S) for understanding ancient biogeochemical cycles, many studies focus on specific time-points of interest, such as the end-Permian mass extinction (EPME). We have generated an 80 million-year Permian–Triassic δ 34 S evap curve from the Staithes S-20 borehole, Yorkshire, England. The Staithes δ 34 S evap record replicates the major features of the global curve, while confirming a new excursion at the Olenekian/Anisian boundary at ~ 247 million years ago. We incorporate the resultant δ 34 S evap curve into a sulphur isotope box model. Our modelling approach reveals three significant pyrite burial events (i.e. PBEs) in the Triassic. In particular, it predicts a significant biogeochemical response across the EPME, resulting in a substantial increase in pyrite burial, possibly driven by Siberian Traps volcanism. Our model suggests that after ~ 10 million years pyrite burial achieves relative long-term stability until the latest Triassic.