Figure F2. Boundary between olivine gabbro (Interval 15) and olivine-bearing gabbronorite (Interval 16) (Thin Section 21; Sample 345-U1415I-4R-1, 31–40 cm [Piece 6]) in the layered series of lithologic Unit II. A. Core close-up. Red box indicates the position from which the thin section shown in B and C was cut. B. Note the sutured boundary (arrows) without any discontinuity between domains. A moderate to strong magmatic foliation is visible and mainly defined by subparallel alignment of tabular plagioclase and elongated anhedral olivine in olivine gabbro. Contact between the two lithologies is parallel to the foliation and sutured, implying the coexistence of two lithologically different crystal mushes in the hyper solidus regime. The type of the contact is modal, in combination with a slight change in average plagioclase grain size (2 mm in olivine-bearing gabbronorite; 2.5 mm in olivine gabbro. Plane-polarized light. C. Under crossed polars.
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