Figure F5. Chilled-margin alteration. A. Chlorite (Chl) vugs and veins (Sample 309-1256D-149R-1, 8–10 cm). B. Chlorite-quartz (Qtz) filled vug surrounded by chilled margin consisting of mixed anorthite-albite (An-Ab) and clinopyroxene (CPX) (Sample 309-1256D-143R-1, 34–38 cm). C. Clasts of quartz in a chilled margin (Sample 309-1256D-143R-1, 34–38 cm). Note fine, light gray banding in quartz grains is compositionally indistinguishable from the surrounding quartz in electron dispersive spectroscopy. D. Pyrite grains (FeS) mixed with anorthite and quartz (Sample 309-1256D-149R-1, 76–79 cm). E. Vein of anhydrite, actinolite (Act), and chlorite (Sample 309-1256D-161R-2, 6–8 cm). F. Anhydrite surrounded by blades of iron oxide (Sample 309-1256D-149R-1, 76–79 cm).
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