Fig. 7: Modal abundance of orthopyroxene (volume %) versus mean F content of mineral phases in Kaapvaal peridotites.
From: The role of C-O-H-F-Cl fluids in the making of Earth’s continental roots
a F content of orthopyroxene and clinopyroxene in garnet lherzolites and orthopyroxene-rich harzburgites from the Kaapvaal craton. Vectors show the effects of melt- and fluid-rock reactions on mantle residues, which are depleted in F (e.g., depleted MORB mantle has 12 µg/g F)103. The volume of fluid controls the magnitude of the increase in excess modal orthopyroxene (garnet and phlogopite) and fluorine concentration. b Same as for (a) except the maximum value of the y-axis scale is increased to also include olivine, and the minimum value of the x-axis scale is increased so that only orthopyroxene-rich garnet harzburgites are shown. Data are from this work (Supplementary Data 1).
