Figure F273. Vein trending from top left to bottom right is an actinolite-magnetite vein, whereas the vein trending from bottom left to top right is a chlorite-quartz-titanite vein (Thin Section 18; Sample 312-1256D-179R-1, 5–9 cm) (plane-polarized light; field of view = 14.5 mm). Crosscutting relationships indicate that the actinolite-magnetite vein predates the chlorite-quartz-titanite vein, consistent with the observation that the actinolite-magnetite vein has been faulted whereas the chlorite-quartz-titanite vein has not. Both veins cut across the dike margin in the right of the image and thus postdate the dike intrusion.
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