Figure F6. A. Plagioclase shape-preferred orientation (SPO) defining magmatic foliation in orthopyroxene-bearing olivine gabbro (Sample 345-U1415G-1R-1, 21–26 cm [Piece 5]; under crossed polars). B–E. Sample 345-U1415G-1R-1, 10–16 cm (Piece 3). B. Moderate to strong plagioclase SPO and moderate olivine SPO defined by tabular, partially skeletal olivine crystals (clinopyroxene oikocryst-bearing troctolite; red arrow; plane-polarized light). Red box (tick mark shows upward direction) indicates location of image in C. C. Plagioclase SPO with equilibrated clusters of polygonal plagioclase with 120° grain junctions. D. Plagioclase SPO foliation wrapping around a 1.5 cm diameter clinopyroxene oikocryst. Plagioclase crystals within the oikocryst are smaller, more elongate, and relatively sparse compared to those outside the oikocryst; no olivine crystals are present within the oikocryst. Red box (tick mark shows upward direction) indicates location of image in E. E. Glomerocrystic arrangement of the plagioclase crystals within a large clinopyroxene oikocryst (under crossed polars).
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