Figure F64. Close-up photographs of examples of alteration veins and their crosscutting relationships in troctolites from Hole 1275D. A. Light gray, altered, magmatic vein crosscutting troctolite. The vein exhibits orthogonal extension fractures filled with cream-colored picrolite serpentine that are in turn crosscut by a white carbonate-Fe oxyhydroxide vein that is parallel to the magmatic vein (interval 209-1275D-17R-2, 102–111 cm). B. Discrete green picrolite vein and a parallel-trending carbonate vein traversing a troctolite (interval 209-1275D-11R-2, 11–20 cm). C. Troctolite cut by gray, altered magmatic veins, showing crosscutting carbonate veins. Note that the carbonate vein in the bottom left-hand corner follows the trace of the magmatic vein (interval 209-1275D-10R-1, 34–49 cm). D. Altered, gray magmatic veins cutting a troctolite. The magmatic veins have been subsequently exploited by a later green picrolite vein and by an even later crosscutting carbonate vein (interval 209-1275D-10R-3, 98

Figure F64. Close-up photographs of examples of alteration veins and their crosscutting relationships in troctolites from Hole 1275D. A. Light gray, altered, magmatic vein crosscutting troctolite. The vein exhibits orthogonal extension fractures filled with cream-colored picrolite serpentine that are in turn crosscut by a white carbonate-Fe oxyhydroxide vein that is parallel to the magmatic vein (interval 209-1275D-17R-2, 102–111 cm). B. Discrete green picrolite vein and a parallel-trending carbonate vein traversing a troctolite (interval 209-1275D-11R-2, 11–20 cm). C. Troctolite cut by gray, altered magmatic veins, showing crosscutting carbonate veins. Note that the carbonate vein in the bottom left-hand corner follows the trace of the magmatic vein (interval 209-1275D-10R-1, 34–49 cm). D. Altered, gray magmatic veins cutting a troctolite. The magmatic veins have been subsequently exploited by a later green picrolite vein and by an even later crosscutting carbonate vein (interval 209-1275D-10R-3, 98–106 cm).