Enhanced weathering as a trigger for the rise of atmospheric O₂ level from the late Ediacaran to the early Cambrian.

ABSTRACT: A shift toward a higher oxygen level in both ocean and atmosphere systems during the late Ediacaran to the early Cambrian has been suggested from multiple indirect proxies. However, the mechanism and magnitude of this oxidation remain unclear. To solve this issue, we measured carbon isotopes in both carbonate and organic matter as well as their trace element compositions for an Ediacaran-Cambrian sequence in the Lower Yangtze basin, South China. The δ¹³C_org and δ¹³C_carb excursions of this sequence are coupled and can be compared with contemporaneous global carbon isotope curves. A 2‰ rise in Δ¹³C_carb-org occurred from the late Ediacaran to the early Cambrian, suggesting a substantial increase in atmospheric oxygen level from

SUBMITTER: Li WP 

PROVIDER: S-EPMC6650434 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature