Large igneous provinces (LIPs) are formed through the rapid emplacement of millions of km3 of magma over geologically short timescales, <1 million years. Owing to their coincidence with many mass extinctions, gases such as CO2 released during LIP emplacement are thought to have triggered catastrophic climate changes. The Central Atlantic Magmatic Province (CAMP), for example, is linked to the end-Triassic mass extinction, one of the ‘Big Five’. However, the volume and relative contributions of sedimentary, crustal and mantle CO2 released by CAMP are unconstrained.
Manfredo Capriolo, from the University of Padova, Italy, and colleagues analysed CO2 trapped in melt inclusions of CAMP basaltic rocks using a combination of petrographic, spectroscopic and geochemical approaches. CO2 concentrations up to 1 wt% were identified for CAMP magmas and application of petrological barometers reveal that this CO2 is likely derived from the mantle and/or the mid-crust to lower-crust. Such high concentrations of CO2 indicate that up to 105 gigatons of CO2 may have been released during CAMP emplacement. This CO2 could have acted as a propellant for the rising magma, explaining why the periodic CAMP eruptions were fast and left little time for the environment to adjust to the increased atmospheric CO2 concentrations. For example, one magmatic episode of only 500 years could have emitted a volume of CO2 equivalent to that projected to be emitted during the 21st century, assuming a 2 °C climate warming scenario. This finding suggests parallels between the end-Triassic mass extinction and the near-future impacts of anthropogenic climate change.
Though the impact of CAMP-related CO2 emissions on the Triassic climate and biosphere were not modelled here, the estimates lend further evidence to the role of CAMP in one of the great mass extinctions. Continued research into connections between volcanic degassing, climate and biosphere responses not only reveals Earth’s history, but offers insights into the sixth mass extinction as Earth heats up.
Capriolo, M. et al. Deep CO2 in the end-Triassic Central Atlantic Magmatic Province. Nature Communications 11, 1670 (2020)
About this article
Cite this article
Zinke, L. End-Triassic carbon runs deep. Nat Rev Earth Environ 1, 235 (2020). https://doi.org/10.1038/s43017-020-0052-z