Figure F16. Typical pieces of rock recovered from Hole U1415J showing characteristic textural and modal differences between Unit II and III lithologies. A–C. Modal and grain size layering in Unit II (Oikocryst-Bearing Layered Gabbro Series) is parallel to foliation. D, E. In contrast, layering is very rare in Unit III (Troctolite Series), but foliation is still common although weaker compared to Unit II. Core image in E shows one of the rare examples of modal and grain size variation observed in the lower part of Unit III. Note the change of foliation dip between the different units (subvertical for the troctolites of Unit III). (A) Troctolite (Sample 345-U1415J-5R-2, 0–21.5 cm [Piece 1]; Interval 29; wet image). (B) Olivine-bearing gabbro (Sample 345-U1415J-8R-3, 30–42 cm [Piece 6]; Interval 48; wet image). (C) Clinopyroxene oikocryst-bearing troctolite. Note the centimeter-sized clinopyroxene oikocrysts wrapped by much finer grained, strongly foliated troctolitic matrix (Sample 345-U1415J-8R-3, 76–91 cm [Piece 9]; Interval 49; dry image). (D) Troctolite (Sample 345-U1415J-18R-1, 96–106 cm [Piece 14]; Interval 71; dry image). (E) Troctolite with modal boundary (Sample 345-U1415J-18R-1, 128–130 cm [Piece 17A]; Interval 72; dry image).
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