Figure F24. Variability of olivine and plagioclase replacement across different lithologies, Site U1415. Cpx = clinopyroxene, Chl = chlorite, Ol = olivine, Pl = plagioclase, Pr = prehnite, Serp = serpentine. A. Olivine gabbro showing radial cracks in plagioclase interpreted as resulting from the apparent volume increase associated with serpentinization of olivine (Thin Section 21; Sample 345-U1415I-4R-1, 35–38 cm [Piece 6]) B. Similar olivine alteration in olivine gabbro in the Multitextured Layered Gabbro Series (Unit II), Hole U1415P. Coronitic textures are moderately well developed, but clinopyroxene and plagioclase are nearly fresh (Thin Section 96; Sample 345-U1415P-3R-1, 113–115 cm [Piece 7]). C. Complete pseudomorphic replacement of plagioclase in association with strongly serpentinized olivine and prehnite veins in the Troctolitic Series (Unit III), Hole U1415P. Coronitic textures are absent from these relict olivine grains. (Thin Section 140; Sample 345 U1415P-22R-1, 113–115 cm [Piece 7]).
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