Abstract
The Early Triassic records the largest inorganic carbon isotope excursions of the Phanerozoic. The causes of these enormous δ13C shifts remain unclear. Here, we present a new high-resolution marine carbonates δ13C record from the Yashan section in the northeastern Yangtze Platform of South China. The δ13C profile shows two significant positive excursions (with maximum δ13C values of ∼ +6‰ and ∼ +9‰, respectively) at the Induan–Olenekian boundary and Smithian–Spathian boundary, which is similar to what is recorded in the shallow platform in Nanpanjiang Basin and in the upper Yangtze Platform area. Negative δ13C excursions during the Griesbachian–early Dienerian, Smithian and middle Spathian, are coincident with warming intervals and accounted for by coeval peaks of volcanic activity (e.g., the release of CO2 from the Siberian Traps and arc volcanism). Enhanced marine primary productivity, as a final effect of massive carbon release, could account for the two positive δ13C excursions, with minor influence of local effects on the magnitude of the shifts. Although the age of volcanism after the Permian–Triassic mass extinction is still not constrained, more lines of evidence support a volcanism-temperature-weathering-productivity mechanism of δ13C perturbations during the Early Triassic.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.