Figure F99. A. Olivine gabbronorite (Sample 305-U1309D-161R-2, 50–53 cm) (plane-polarized light). Primary nonreactive olivine (right)/orthopyroxene contact (upper left). Olivine is partially replaced by tremolite-talc-oxide. B. Olivine-orthopyroxene-bearing gabbro (Sample 305-U1309D-166R-3, 55–57 cm) (cross-polarized light). A 200–300 µm thick orthopyroxene film rims olivine at the contact with plagioclase. A thinner discontinuous film is also visible between clinopyroxene and olivine (lower right olivine grain). C. Pigeonitic gabbronorite (Sample 305-U1309D-254R-2, 33–35 cm) (cross-polarized light). Two inverted pigeonites show a (001) primary exsolution pattern. A double (100) twinning in the larger central grain possibly reflects high-temperature kink banding.
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