Plate 1. 1. SEM photomicrograph of vesicle filling within the oxidation halo (enlarged area on the right side). Within vesicle, light gray = iddingsite and dark gray = celadonite; white bar = 50 µm. Sample 168-1026C-17R-1, 13-17 cm (Piece 4). 2. SEM photomicrograph of vesicles filling within the oxidation halo (enlarged area on the right side). Within vesicles, light gray = iddingsite and dark gray = celadonite; white bar = 50 µm. Sample 168-1026C-17R-1, 13-17 cm (Piece 4). 3. Photomicrograph of simple vein in glassy margin of Sample 168-1027C-1R-6, 67-70 cm (Piece 2). The layering within the vein is described in the text and sketched in Figure 9A (vein width = 0.5 mm; plane-polarized light). 4. SEM photomicrograph of pseudomorphic replacement of carbonate (light gray) and Fe-rich saponite (dark gray) after olivine. Saponite fills olivine fractures and is also associated with carbonate in the outer rim of the carbonate clasts. White bar = 100 µm. Sample 168-1027C-5R-5, 22-27 cm (Piece 2).

Plate 1. 1. SEM photomicrograph of vesicle filling within the oxidation halo (enlarged area on the right side). Within vesicle, light gray = iddingsite and dark gray = celadonite; white bar = 50 µm. Sample 168-1026C-17R-1, 13-17 cm (Piece 4). 2. SEM photomicrograph of vesicles filling within the oxidation halo (enlarged area on the right side). Within vesicles, light gray = iddingsite and dark gray = celadonite; white bar = 50 µm. Sample 168-1026C-17R-1, 13-17 cm (Piece 4). 3. Photomicrograph of simple vein in glassy margin of Sample 168-1027C-1R-6, 67-70 cm (Piece 2). The layering within the vein is described in the text and sketched in Figure 9A (vein width = 0.5 mm; plane-polarized light). 4. SEM photomicrograph of pseudomorphic replacement of carbonate (light gray) and Fe-rich saponite (dark gray) after olivine. Saponite fills olivine fractures and is also associated with carbonate in the outer rim of the carbonate clasts. White bar = 100 µm. Sample 168-1027C-5R-5, 22-27 cm (Piece 2).