Figure F3. The groundmass of fresh rhyodacite in the uppermost part of Hole 1191A consists of about equal proportions of volcanic glass and fine microcrystalline plagioclase needles, which are generally aligned (Sample 193-1191A-1R-1 [Piece 2, 5-11 cm] in plane-polarized light; width of view = 1.38 mm. Photomicrograph ID# 1191A

Figure F3. The groundmass of fresh rhyodacite in the uppermost part of Hole 1191A consists of about equal proportions of volcanic glass and fine microcrystalline plagioclase needles, which are generally aligned (Sample 193-1191A-1R-1 [Piece 2, 5-11 cm] in plane-polarized light; width of view = 1.38 mm. Photomicrograph ID# 1191A_1; thin section 47).