Figure F45. Hydrothermal brecciation has generated a clastic zone within an exceptionally large vein in coherent volcanic rock (Unit 26). The clasts are more intensely altered than the surrounding volcanic groundmass, and some have been moved relative to each other (Sample 193-1189B-16R-1, 7-15 cm).

Figure F45. Hydrothermal brecciation has generated a clastic zone within an exceptionally large vein in coherent volcanic rock (Unit 26). The clasts are more intensely altered than the surrounding volcanic groundmass, and some have been moved relative to each other (Sample 193-1189B-16R-1, 7-15 cm).