Fig. 3: Variations of hydrogen and halogen abundances in lunar silicate minerals.
From: Halogen abundance evidence for the formation and metasomatism of the primary lunar crust

a Variation of Cl and H concentrations in lunar silicate minerals. b Variation of F and Cl concentrations in lunar silicate minerals. F/Cl ratio fields of minerals (plagioclase and orthopyroxene) crystallized from magma with low F/Cl ratios (0.5-4.4, KREEP-like) and high F/Cl ratios (lunar mantle-like) are plotted. The hydrogen addition trend by asteroid or comet impacts comes from ref. 28. Literature data include Apollo materials28 and meteoritic plagioclases (NWA 5744 and 10140)29.