Figure F65. Gabbro and olivine gabbro (under crossed polars). A, B. Olivine gabbro (Sample 345-U1415J-3R-1, 22–24 cm [Piece 6]). A. Whole thin section image showing large (as long as 8 mm), high–aspect ratio (10:1) twinned clinopyroxene crystals that define very strong lineation (red arrow) within weak plagioclase foliation and more numerous smaller, equant clinopyroxene crystals. Red box (tick mark shows upward direction) indicates location of image in B. B. Margin of one of the large, elongate clinopyroxene crystals showing a seriate grain boundary with the adjacent annealed plagioclase crystals. C, D. Gabbro (Sample 345-U1415J-3R-1, 79–82 cm [Piece 16]). C. Large plagioclase crystals with significant deformation twinning and bending but weakly developed grain boundary annealing. D. Relatively coarse plagioclase grain size (2–5 mm) and moderate plagioclase foliation (red arrow). Red box indicates location and orientation of image in C.
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