Figure F26. Downhole variation of vein mineralogy plotted with running average of lithology. The overall downcore distribution of veins is relatively homogeneous. Except for a possible occurrence shallow in the hole (not confirmed by XRD or thin section), zeolites first appear near 700 mbsf and then increase regularly to the bottom of the hole. Secondary sulfide minerals are most common in the upper 400 m of Hole U1309D.