Figure F4. Orthopyroxene-bearing gabbro with two domains corresponding to different lithologies (Thin Section 1; Sample 345-U1415E-1R-1, 21–23 cm [Piece 3]; thin section length = 3.4 cm). A, B. Two domains (red lines) consisting of orthopyroxene-bearing gabbro and disseminated oxide gabbronorite: (A) under crossed polars; (B) plane-polarized light. Note the presence of large orthopyroxene (opx) and oxide minerals (black) in the disseminated oxide gabbronorite domain, whereas the orthopyroxene-bearing gabbro is characterized by clinopyroxene tending to form a subophitic network with more lath shaped plagioclase of smaller grain size. C, D. Plagioclase in disseminated oxide gabbronorite (yellow arrow) bears inclusions of oxide minerals; C is under crossed polars and D is under plane-polarized light.
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