Figure F44. Discordant intrusive contacts between relatively fine grained olivine gabbro and troctolite. A. Moderately well foliated olivine gabbro (Sample 345-U1415P-3R-1, 30–34 cm [Piece 7]). Red box (tick mark shows upward direction) indicates location of image in D. B. Intrusive contact between orthopyroxene-bearing olivine gabbro (top) and troctolite (bottom). The contact truncates both olivine grains in the troctolite and is discordant to the steeply dipping olivine foliation in the same unit (Sample 345-U1415P-18R-1, 78–83 cm [Piece 7]). Red box indicates location of image in E. C. Altered contact between olivine gabbro (bottom) and troctolite (top). The boundary between troctolite and olivine gabbro truncates steeply dipping olivine foliation and individual olivine grains in the troctolite (Sample 345-U1415P-22R-2, 103–112 cm [Piece 8]). Red box indicates location of image in F. D. Moderate magmatic foliation of olivine gabbro defined by a plagioclase shape-preferred orientation (SPO) that wraps locally around relatively large clinopyroxene crystals (Thin Section 96). Red boxes indicate location of Figures F45A–F45C. E. Moderate magmatic foliation defined by plagioclase SPO that parallels the contact between orthopyroxene-bearing olivine gabbro and troctolite (Thin Section 130). Red boxes indicate location of Figures F45E and F45F. F. Contact between olivine gabbro and troctolite shown in C (Thin Section 140). Red box (with tick mark showing up) indicates the location of image in Figure F45D. D–F are under crossed polars.
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