Figure F1. Photomicrographs showing the primary minerals of basalts from Site 1201. A. Microphenocrysts and microlites of plagioclase, clinopyroxene, and magnetite in vesicular, altered basalt (Sample 195-1201D-46R-5, 8–11 cm; plane-polarized light). B. Microphenocryst of plagioclase showing the core replaced by green clay minerals and preserved Na-rich rims (Sample 195-1201D-48R-2, 74–76 cm; plane-polarized light). C. Microlites of clinopyroxene arranged in spherulitic texture within a vesicular, altered glassy groundmass (Sample 195-1201D-46R-5, 8–11 cm; cross-polarized light). D. Nearly fresh plagioclase, clinopyroxene, and Ti magnetite in sheet basalt with subophitic texture (Sample 195-1201D-55R-1, 103

Figure F1. Photomicrographs showing the primary minerals of basalts from Site 1201. A. Microphenocrysts and microlites of plagioclase, clinopyroxene, and magnetite in vesicular, altered basalt (Sample 195-1201D-46R-5, 8–11 cm; plane-polarized light). B. Microphenocryst of plagioclase showing the core replaced by green clay minerals and preserved Na-rich rims (Sample 195-1201D-48R-2, 74–76 cm; plane-polarized light). C. Microlites of clinopyroxene arranged in spherulitic texture within a vesicular, altered glassy groundmass (Sample 195-1201D-46R-5, 8–11 cm; cross-polarized light). D. Nearly fresh plagioclase, clinopyroxene, and Ti magnetite in sheet basalt with subophitic texture (Sample 195-1201D-55R-1, 103–106 cm; cross-polarized light).