Figure F3. Flow banding defined by light- and dark-colored groundmass can be observed in Unit 1 (Sample 193-1190C-3R-1 [Piece 3, 7-9 cm]. Photomicrograph ID# 1190C_1; thin section 46). A. In thin section, dark brown groundmass domains form lensoidal to wavy bands and are enriched in microvesicles. Width of view = 5.5 mm. B. Enlargement of white square shown in (A). Width of view = 0.7 mm × 0.55 mm. In detail, dark brown groundmass domains are enriched in plagioclase microcrysts, whereas light brown groundmass contains about equal proportions of volcanic glass and microcrysts. The contact between these groundmass domains is gradational (Photomicrograph ID# 1190C

Figure F3. Flow banding defined by light- and dark-colored groundmass can be observed in Unit 1 (Sample 193-1190C-3R-1 [Piece 3, 7-9 cm]. Photomicrograph ID# 1190C_1; thin section 46). A. In thin section, dark brown groundmass domains form lensoidal to wavy bands and are enriched in microvesicles. Width of view = 5.5 mm. B. Enlargement of white square shown in (A). Width of view = 0.7 mm × 0.55 mm. In detail, dark brown groundmass domains are enriched in plagioclase microcrysts, whereas light brown groundmass contains about equal proportions of volcanic glass and microcrysts. The contact between these groundmass domains is gradational (Photomicrograph ID# 1190C_2; thin section 46).