Figure F157. Microstructural characters of magmatic and plastic foliations. A. Magmatic foliation with no crystal-plastic overprint (Sample 305-U1309D-189R-3, 103–105 cm) (cross-polarized light; field of view [FOV] = ~2 cm). See also Figure F24. B. High-temperature/low-stress crystal-plastic foliation (Sample 305-U1309D-212R-1, 111–113 cm) (cross-polarized light; FOV = ~2 cm). Note dynamic recrystallization of plagioclase and olivine. Crystal-plastic strain probably overprints a preexisting magmatic foliation. See also Figure F25. C. Mylonitic foliation (low temperature/high stress) with relict plagioclase and clinopyroxene porphyroclasts (Sample 305-U1309D-137R-2, 96–98 cm) (cross-polarized light; FOV = ~2 cm). Note dextral sense of shear. D. Olivine-rich troctolite with alignment, probably magmatic, of weakly elongated olivines (Sample 305-U1309D-248R-2, 107–110 cm) (cross-polarized light; FOV = ~2 cm). Note that poikilitic plagioclase and clinopyroxene grains are not elongated parallel to the foliation.
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