Figure F34. Photomicrographs of magnetite produced by exsolution from silicates in gabbros of Hole 735B. TiO2 amounts from XRF data and values for magnetic susceptibility below are from the site report (Shipboard Scientific Party, 1999b). Photomicrograph identifications in brackets giving role and photo number (e.g., 7-19) are from the photolog file in the supplemental material portion of the Leg 176 Initial Reports volume (Dick, Natland, Miller, et al., 1999). A. Sample 176-735B-155R-1 (Piece 2, 10-13 cm) in transmitted light (photo 7-19). Olivine gabbro, lithologic interval 731, TiO2 = 0.40%, magnetic susceptibility = 810 [10-13 cm. Exsolved oxides concentrated in cleavage adjacent to orthogonal cracks in clinopyroxene. B. Same view as A in reflected light (photo 7-20). C. Same sample as A exsolved oxides along cleavage in another clinopyroxene (photo 7-12). D. Same view as C in reflected light (photo 7-14). The arrow points from a swirl of tiny oxides in C toward the more magnified corresponding swirl in D. E. Sample 176-735B-158R-5 (Piece 4, 135-141 cm) in transmitted light (photo 7-25). Leucocratic disseminated oxide olivine gabbro, lithologic interval 769, TiO2 = 1.04%, magnetic susceptibility = 902 x 10-6 MU. Exsolved oxides in partings in olivine. The partings are oblique to the plane of the thin section. A train of secondary inclusions is oblique to the partings. F. Same view as E in reflected light (photo 7-26). The train of secondary inclusions consists of rows of tiny open pits without oxide minerals. The partings in E appear in this view as tiny rows of oxides where they intersect the polished surface of the mineral. G. Sample 176-735B-155R-4 (Piece 1, 1-4 cm) in reflected light (photo 7-23). Olivine gabbro, lithologic Interval 732, TiO2 = 0.28%, magnetic susceptibility = 659 x 10-6 MU. Oxide minerals are in partings in the olivine. H. Sample 176-735B-137R-3 (Piece 2A, 34-38 cm) in transmitted light (photo 8-08). Olivine gabbro, lithologic interval 679, TiO2 = 0.35%, magnetic susceptibility = 237 x 10-6 MU. Magnetite rods exsolved from plagioclase. Also shown in Shipboard Scientific Party, 1999b, figure 18.

Figure F34. Photomicrographs of magnetite produced by exsolution from silicates in gabbros of Hole 735B. TiO₂ amounts from XRF data and values for magnetic susceptibility below are from the site report (Shipboard Scientific Party, 1999b). Photomicrograph identifications in brackets giving role and photo number (e.g., 7-19) are from the photolog file in the supplemental material portion of the Leg 176 Initial Reports volume (Dick, Natland, Miller, et al., 1999). A. Sample 176-735B-155R-1 (Piece 2, 10-13 cm) in transmitted light (photo 7-19). Olivine gabbro, lithologic interval 731, TiO₂ = 0.40%, magnetic susceptibility = 810 [10-13 cm. Exsolved oxides concentrated in cleavage adjacent to orthogonal cracks in clinopyroxene. B. Same view as A in reflected light (photo 7-20). C. Same sample as A exsolved oxides along cleavage in another clinopyroxene (photo 7-12). D. Same view as C in reflected light (photo 7-14). The arrow points from a swirl of tiny oxides in C toward the more magnified corresponding swirl in D. E. Sample 176-735B-158R-5 (Piece 4, 135-141 cm) in transmitted light (photo 7-25). Leucocratic disseminated oxide olivine gabbro, lithologic interval 769, TiO₂ = 1.04%, magnetic susceptibility = 902 x 10^-6 MU. Exsolved oxides in partings in olivine. The partings are oblique to the plane of the thin section. A train of secondary inclusions is oblique to the partings. F. Same view as E in reflected light (photo 7-26). The train of secondary inclusions consists of rows of tiny open pits without oxide minerals. The partings in E appear in this view as tiny rows of oxides where they intersect the polished surface of the mineral. G. Sample 176-735B-155R-4 (Piece 1, 1-4 cm) in reflected light (photo 7-23). Olivine gabbro, lithologic Interval 732, TiO₂ = 0.28%, magnetic susceptibility = 659 x 10^-6 MU. Oxide minerals are in partings in the olivine. H. Sample 176-735B-137R-3 (Piece 2A, 34-38 cm) in transmitted light (photo 8-08). Olivine gabbro, lithologic interval 679, TiO₂ = 0.35%, magnetic susceptibility = 237 x 10^-6 MU. Magnetite rods exsolved from plagioclase. Also shown in Shipboard Scientific Party, 1999b, figure 18.