Fig. 23

Photomicrographs of veins from the Yuli Belt. White arrow shows the coordinate direction, and plunge and trend indicate the view direction and pole to the plane of the thin section. a, b (XPL)) Late-stage vein cross-cutting the S₄ fabric at a high angle. The vein features quartz, adularia, and ilmenite. Elongate grain morphologies are observable along the vein/wall rock contact, and blocky grains with slight undulose extinction are dominate in the center of the vein. c, d (XPL) Late-stage vein composed of quartz, albite, and uncommon chlorite cross-cutting S₄ characterized by ductile deformation along an S₄ cleavage domain. Elongate grain morphologies are observable along the vein/wall rock contact, and blocky grains with slight undulose extinction are dominant in the center of the vein. e, f (XPL) Thin vein with adjacent grains showing a grain preferred orientation indicating northeast-side-down normal offset