Figure F1. Microphotographs of typical rock textures of Gabbros 1 and 2 and lower dike screen. A. Boundary between subophitic and coarse-grained network domains in oxide-bearing gabbro (Gabbro 1) (Sample 312-1256D-214R-2, 78–81 cm; 1413.13 mbsf). Network domain has distinct exsolution lamellae. B. Same as A (cross-polarized light). Clinopyroxene with exsolution lamellae replaces poikilitic clinopyroxene in subophitic domain. Clinopyroxenes of both domains are igneous-type. Plagioclase in the coarse-grained network domain shows normal zoning. C. Disseminated oxide gabbronorite (Gabbro 2), which consists of Fe-Ti oxide, clinopyroxene, orthopyroxene, and plagioclase with cloudy core and clear rim due to numerous submicrometer opaque inclusions (Sample 312-1256D-232R-2, 10–14 cm; 1494.08 mbsf). Both orthopyroxene and clinopyroxene are recrystallized to green and brown amphibole. D. Disseminated oxide gabbronorite (Gabbro 2) (Sample 312-1256D-231R-2, 95–98 cm, 1490.14 mbsf). Amphibole intergrowth–type clinopyroxenes are partially replaced by green and brown amphibole and Fe-Ti oxides a few to a few tens of micrometers in diameter. E. Area adjacent to D, same thin section. Igneous type clinopyroxene characterized by exsolution lamellae with sub-micrometer-sized opaque minerals. F. Type 8 metabasalt (lower dike screen), showing granular texture like oxide gabbronorite (Sample 312-1256D-233R-1, 4–7 cm; 1497.50 mbsf). Secondary clinopyroxene with very low TiO2 forms a cluster or vein. Small cluster is visible at the center right. G. Type 8 metabasalt (lower dike screen) (Sample 312-1256D-234R-1, 1–2 cm; 1502.50 mbsf). 0.5 to 1.0 mm size euhedral plagioclase laths and relict clinopyroxene are embedded in the matrix of microgranular secondary clinopyroxene, orthopyroxene, plagioclase and Fe-Ti oxides. Plagioclase lath has granular opaque and transparent inclusions a few micrometers in diameter. H. Same as G (cross-polarized light). pl = plagioclase, cpx = clinopyroxene, amp = amphibole, ox = Fe-Ti oxide, opx = orthopyroxene.
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