Plate P2. Photomicrographs of felsic and plagioclase-rich veins showing common presence of euhedral, strongly zoned plagioclase crystals. 1. Euhedral plagioclase crystals in vein center, showing minor zoning and presence of dark aphanitic material between the grains (Sample 176-735B-126R-5, 101-106 cm). 2. A large, nearly euhedral plagioclase crystal showing typically pitted and corroded core and clear rims. Note the rounded end of the pitted core in the upper left and the euhedral overgrowth of more sodic plagioclase (Sample 176-735B-153R-1, 33-39 cm). 3. Large euhedral to subhedral, strongly zoned plagioclase in center of vein. The cores of the plagioclase grains show little pitting or corrosion. The space between the plagioclase grains (blue) is filled with late-stage quartz in optical continuity (Sample 176-735B-130R-3, 52-58 cm). 4. Strongly corroded, subhedral plagioclase grains in felsic vein. Note the dark, pitted plagioclase cores and clear, white rims and overall porous nature of the vein (Sample 176-735B-157R-7, 1-5 cm). All scale bars = 1 mm.

Plate P2. Photomicrographs of felsic and plagioclase-rich veins showing common presence of euhedral, strongly zoned plagioclase crystals. 1. Euhedral plagioclase crystals in vein center, showing minor zoning and presence of dark aphanitic material between the grains (Sample 176-735B-126R-5, 101-106 cm). 2. A large, nearly euhedral plagioclase crystal showing typically pitted and corroded core and clear rims. Note the rounded end of the pitted core in the upper left and the euhedral overgrowth of more sodic plagioclase (Sample 176-735B-153R-1, 33-39 cm). 3. Large euhedral to subhedral, strongly zoned plagioclase in center of vein. The cores of the plagioclase grains show little pitting or corrosion. The space between the plagioclase grains (blue) is filled with late-stage quartz in optical continuity (Sample 176-735B-130R-3, 52-58 cm). 4. Strongly corroded, subhedral plagioclase grains in felsic vein. Note the dark, pitted plagioclase cores and clear, white rims and overall porous nature of the vein (Sample 176-735B-157R-7, 1-5 cm). All scale bars = 1 mm. Click on image or highlighted number to see enlargement.