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Figure F220. Textural details from a complex zoned dike margin in Unit 1256D-71. A. Spherulitic texture in the outer parts of the chilled margin (left) grades into a variolitic texture toward the dike interior (right). Note the flow alignment (up and down page) of plagioclase microlites in a zone parallel to the chilled margin, to the right of the center line (Thin Section 13; Sample 312-1256D-176R-2, 0–2 cm) (field of view [FOV] = 1.2 mm; plane-polarized light). B. Spherulites are deformed and aligned by flow around the 90° corner in the intrusive contact. Spherulitic material to the right and top intrudes the more crystalline basalt in the lower left corner. Note the bright light-colored vein that follows the north–south part of the contact and extends to the top of the figure. Note also dull brownish former glass on east–west part of contact (Thin Section 13; Sample 312-1256D-176R-2, 0–2 cm) (FOV = 2.4 mm; plane-polarized light).

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