Figure F20. Close-up photograph of Sample 183-1141A-22R-3 (Piece 2, 10-24 cm) showing megavesicle horizon marking the change from the more vesicular upper part of the lava to the more massive interior of basement Unit 6. Vesicles are filled with banded agate filling and have multiple generations of light brown carbonates along their margins. Also shown is a patch of basalt with a variolitic texture altered to light pink and green clay.