Figure F38. Photomicrographs of harzburgite, orthopyroxene, dunite, and a chromitite layer from Hole 1271B. Ol = olivine, Opx = orthopyroxene, Sp = spinel, Tr = tremolite. A. Protointergranular orthopyroxene bastite in protointergranular harzburgite (Sample 209-1271B-6R-1 [Piece 2, 8–11 cm]) (cross-polarized light [XPL]: blue filter; field of view [FOV] = 5.5 mm; image 1271B_108). B. Talc-chlorite-tremolite-magnetite pseudomorph of a stretched orthopyroxene rimmed by vermicular spinel within a sample of orthopyroxene dunite. Red arrows show sense of rotation due to shear prior to spinel precipitation and indicate normal sense shear (Sample 209-1271B-17R-1 [Piece 10, 60–62 cm]) (plane-polarized light [PPL]; FOV = 5.5 mm; image 12741B_130). C. Talc-chlorite-tremolite-magnetite pseudomorph of a stretched orthopyroxene rimmed by vermicular spinel in orthopyroxene dunite. Red arrows show sense of rotation due to shear prior to spinel precipitation and indicate normal sense shear (Sample 209-1271B-17R-1 [Piece 10, 60–62 cm]) (PPL; FOV = 5.5 mm; image 1271B_129). D. Primary chrome spinel layer in massive tremolite replacing a contact between dunite and porphyroclastic gneissic gabbro (Sample 209-1271B-14R-1 [Piece 7, 32–35 cm]) (XPL: blue filter; FOV = 5.5 mm; image 1271B

Figure F38. Photomicrographs of harzburgite, orthopyroxene, dunite, and a chromitite layer from Hole 1271B. Ol = olivine, Opx = orthopyroxene, Sp = spinel, Tr = tremolite. A. Protointergranular orthopyroxene bastite in protointergranular harzburgite (Sample 209-1271B-6R-1 [Piece 2, 8–11 cm]) (cross-polarized light [XPL]: blue filter; field of view [FOV] = 5.5 mm; image 1271B_108). B. Talc-chlorite-tremolite-magnetite pseudomorph of a stretched orthopyroxene rimmed by vermicular spinel within a sample of orthopyroxene dunite. Red arrows show sense of rotation due to shear prior to spinel precipitation and indicate normal sense shear (Sample 209-1271B-17R-1 [Piece 10, 60–62 cm]) (plane-polarized light [PPL]; FOV = 5.5 mm; image 12741B_130). C. Talc-chlorite-tremolite-magnetite pseudomorph of a stretched orthopyroxene rimmed by vermicular spinel in orthopyroxene dunite. Red arrows show sense of rotation due to shear prior to spinel precipitation and indicate normal sense shear (Sample 209-1271B-17R-1 [Piece 10, 60–62 cm]) (PPL; FOV = 5.5 mm; image 1271B_129). D. Primary chrome spinel layer in massive tremolite replacing a contact between dunite and porphyroclastic gneissic gabbro (Sample 209-1271B-14R-1 [Piece 7, 32–35 cm]) (XPL: blue filter; FOV = 5.5 mm; image 1271B_117).