Figure F32. Photomicrographs of crystallization of titanomagnetite, Hole U1347A. Depths are at tops of thin section intervals. A, B. Different spherulitic portions of the pillow margin, both showing details of fibrous spherulites that nucleated on tabular and acicular plagioclase crystals (gray). Light-colored needles are clinopyroxene dendrites; darker curving or branching needles are plagioclase. Strongly reflective specks of titanomagnetite are visible in B, which has larger fibrous needles (further into flow interior) but not in A. Top of Flow 2; 174.93 mbsf (Thin Section 78; Sample 324-U1347A-13R-7, 69–72 cm). C. Very fine grained matrix, dotted with titanomagnetite. Orange-colored species are altered interstitial glass with no titanomagnetite. Bottom of Flow 1; 174.21 mbsf (Thin Section 75; Sample 324-U1347A-13R-6, 139–142 cm). D. Reflective titanomagnetite (white) in a segregation vesicle. Gray crystals are plagioclase. Dark area is altered and nonreflective. Lower pillow stack of Unit XIV; 281.25 mbsf (Thin Section 135; Sample 324-U1347A-25R-1, 5–9 cm). E. Elongate skeletal titanomagnetite (white) projecting from intergrown plagioclase and clinopyroxene (light gray), at upper left, toward intersertal patches (nonreflective, dark gray), at lower right. Flow 3; 197.3 mbsf (Thin Section 86; Sample 324-U1347A-16R-2, 100–104 cm). F. Skeletal titanomagnetite (white), mainly at edges of intergrowths of clinopyroxene (light gray) and acicular plagioclase (darker gray), next to altered intersertal patches (dark brown and black and nonreflective). Interior of Flow 1; 161.34 mbsf (Thin Section 71; Sample 324-U1347A-12R-2, 40–42 cm). G. High-magnification image of skeletal titanomagnetite, partly altered and pitted and intergrown with plagioclase. Interior of Flow 3; 200.57 mbsf (Thin Section 89; Sample 324-U1347A-16R-5, 99–108 cm). H. Thin lens of an unaltered glass inclusion dished out against plagioclase lying beneath and thinned to enable viewing of trellislike titanomagnetite (black) and dendritic clinopyroxene (sprays of smaller crystals). Top of Flow 1; 159.62 mbsf (Thin Section 69; Sample 324-U1347A-12R-1, 2–5 cm). C and H are under transmitted light; A, B, and D–G are under reflected light.
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