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Figure F12. Boundary between olivine gabbro and orthopyroxene (Opx)-bearing troctolite interpreted as mafic enclave (red dashed lines). The olivine gabbro host rock is described as an “anorthosite domain” in thin section images because this part of the rock contains only plagioclase due to the heterogeneous distribution of large minerals in the olivine gabbro. Boundary type = grain size and modal; boundary definition = sharp and sutured. For details see “Descriptions of igneous boundaries.” A. Sample 345-U1415P-7R-2, 9.5–56 cm (Piece 2). Blue box indicates the position of thin section in B and C (Thin Section 114; Sample 345-U1415P-7R-2, 41–54 cm [Piece 2]). B. Plane-polarized light. Ol = olivine, Cpx = clinopyroxene, Pl = plagioclase. C. Under crossed polars.

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