Figure F14. Photomicrographs of sparsely to highly plagioclase-olivine phyric basalt, Units 1 and 2. A. Plagioclase phenocryst in Unit 1 with hollow cores parallel to an elongated direction and filled with glass or cryptocrystalline groundmass material (Sample 336-U1383C-3R-1, 3–6 cm [Piece 2], Thin Section 30). B, C. Sample 336-U1383C-6R-1, 39–42 cm (Piece 7), Thin Section 35: (B) spherulites in glass matrix growing out from tiny acicular plagioclase, skeletal plagioclase laths, tabular plagioclase phenocrysts, and granular olivine microphenocrysts, (C) well-developed plagioclase fan-spherulites composed of plumose plagioclase-clinopyroxene intergrowth and interstitial titanomagnetite. D. Plagioclase phenocryst containing glass inclusions as blebs in the core (Sample 336-U1383C-9R-4, 78–80 cm [Piece 9], Thin Section 40). E. Plagioclase phenocryst showing sieve texture with irregularly shaped inclusions of groundmass or glass (Sample 336-U1383C-9R-4, 78–80 cm [Piece 9], Thin Section 40). F. Crystal edge of a plagioclase phenocryst exhibiting dendritic overgrowth in a sharply zoned rim (Sample 336-U1383C-9R-3, 77–80 cm [Piece 10], Thin Section 39).
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