Plate P4. Photomicrographs of various vein minerals in Hole 735B. 1. Full thin section view of an amphibole + plagioclase vein cutting slightly foliated gabbro. Note the sharp but irregular vein margins (Sample 176-735B-19R-5, 62-73 cm). 2. Large, euhedra

Plate P4. 3. Narrow carbonate veins cutting olivine gabbro. Note the rather irregular vein margins and the orientation of crystals within the vein (Sample 176-735B-91R-5, 81-86 cm). All scale bars = 1 mm.