Figure F294. Magmatic flow structures in the sheeted dikes. A. Shape-preferred orientation of plagioclase laths, a trachytic texture, indicates flow (Thin Section 32; Sample 312-1256D-192R-1, 11–13 cm) (cross-polarized light; field of view [FOV] = 2.25 mm). B. Plagioclase laths oriented parallel to a dike margin (Thin Section 13; Sample 312-1256D-176R-2, 0–2 cm) (plane-polarized light; FOV = 2.25 mm). Undeformed spherulites are present on the left side of the image. C. Flow banding defined by imbricated oxide bands near a chilled margin (Thin Section 13; Sample 312-1256D-176R-2, 0–2 cm) (plane-polarized light; FOV = 2.25 mm). D. Flow banding defined by oxide bands with mutually crosscutting relationships with veins (Thin Section 13; Sample 312-1256D-176R-2, 0–2 cm) (plane-polarized light; FOV = 4.5 mm). E. Stretched spherulites adjacent to an irregularity in a chilled margin (Thin Section 13; Sample 312-1256D-176R-2, 0–2 cm) (plane-polarized light, FOV = 2.25 mm). F. Stretched spherulites and folded vein in a chilled margin (Thin Section 27; Sample 312-1256D-187R-1, 74–77 cm) (cross-polarized light; FOV = 2.25 mm).
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