Figure F224. A. Hypocrystalline variolitic textures in cryptocrystalline basalt from Unit 1256D-75 (Thin Section 26; Sample 312-1256D-187R-1, 17–18 cm) (field of view [FOV] = 4.8 mm; plane-polarized light). B. Irregular banding in cryptocrystalline chilled margin of basalt dike, Unit 1256D-75b (Thin Section 25; Sample 312-1256D-186R-1, 48–53 cm) (FOV = 4.8 mm; plane-polarized light). Note the horizontal (in the image) intrusive contact into more crystalline basalt near the bottom of the image. C. Fragment of the basaltic host rock (Unit 75) in the chilled intrusive margin of Unit 75b (also Thin Section 25).
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