Xu, Q.H.; Wang, L.; Liu, J.; Deloule, E.; Hanski, E.; Gu, X.Y.; Chen, H.; Xia, Q.K.

Journal of Geophysical Research: Solid Earth, 2022, 127, e2022JB024388

Voir en ligne : https://doi.org/10.1029/2022JB024388

Abstract :

The Early Cretaceous Jehol Biota evolution has remarkable spatiotemporal correlation with
the destruction of the North China craton though the coupling mechanism remains enigmatic. The craton
destruction was accompanied by intense magmatic activity and the released volatiles and nutrients might have
had climatic and environmental impacts on the biotic evolution. In this study, we investigated the mentioned
hypothetical causal link by determining concentrations and total emissions of volatile elements (S, F, Cl)
and bulk-rock P contents of volcanic rocks that were erupted during the pre-flourishing, flourishing and
post-flourishing stages of the Jehol Biota. Our results show that the volcanism near the flourishing stage has
lower S (1,083–2,370 ppm), Cl (1,277–5,608 ppm) and higher P2O5 contents (0.48–0.84 wt.%) than that in
the non-flourishing stages with S of 1,991–3,288 ppm, Cl of 7,915–12,315 ppm and P2O5 of 0.17–0.23 wt.%.
Fluorine contents in the three stages vary from 893 to 3,746 ppm. The total volatile emissions are minor in the
flourishing stage (1–14 Gt S, 0.6–10 Gt Cl, 0.6–9 Gt F) but elevated in the non-flourishing stages (2–766 Gt S,
4–1,168 Gt Cl, 1–175 Gt F). Our data suggest that regional climatic and environmental impacts of volcanism
in the non-flourishing stages probably hindered the species diversification. The high P flux released from
lithospheric mantle-derived lavas during the peak time of craton destruction might have enhanced primary
productivity and contributed to the flourishing of the Jehol Biota. Our study provides insights into the
relationship between the biosphere and deep geodynamic processes driven by volcanism.