Phosphorus Variations in Volcanic Sequences Reveal the Linkage Between Regional Tectonics and Terrestrial Biota Evolution

Abstract

The Middle‒Late Mesozoic massive volcanism formed a considerable thickness of volcanic-sedimentary strata in western Liaoning, northern China. Concomitantly, it elevated phosphorus (P) availability for the rapid bloom of the terrestrial Yanliao and Jehol biotas, which developed highly abundant biodiversity and biomass. Hence, systematic tectonic and geochemical analyses of these volcanic-sedimentary sequences with a significant P fluctuation would advance our understanding of the coevolutionary relationship between terrestrial biotas and regional tectonics. Here, we show that the secular variation of P availability in the Mesozoic volcanic rocks were the immediate results of the changes in volcanic intensity and lithospheric thickness controlled by the geological background of the cratonic destruction resulting from the paleo-Pacific plate subduction. This study reveals the constraint effect of regional tectonics on the evolution of terrestrial ecosystems through the volcanism and P cycle.