Figure F21. Close-up photograph of aphyric volcanic rock representative of Unit 28. Siliceous banded alteration halos are related to anhydrite-pyrite veins and produce an apparent clastic texture (interval 193-1188F-1Z-4, 43-60 cm).

Figure F21. Close-up photograph of aphyric volcanic rock representative of Unit 28. Siliceous banded alteration halos are related to anhydrite-pyrite veins and produce an apparent clastic texture (interval 193-1188F-1Z-4, 43-60 cm).