Extended Data Fig. 5: Crustal residence versus δ18O in zircon since 720 Myr ago (A–E).
From: Composition of continental crust altered by the emergence of land plants
It is assumed here that all primary magmas are initially derived from the mantle with a δ18O of ~5.5‰ and a crustal residence time less than ~250 Myr (approximating the depleted mantle compositions61). The degree of correlation between εHf and δ18O in zircon is markedly different in the latter two panels (A and B), with the panels covering pre-430 Myr ago showing greater degrees of scatter and weak correlations. (F) r2 versus slope of the regression from 700 Myr ago to 0 Myr ago in 10 Myr steps using a rolling window.
