Fig. 38. Supposed replacement veins of quartz, K-feldspar, and oligoclase in metavolcanic rocks, 16 meters from the contact of the Glen Alpine granodiorite. The veinlets are elongated perpendicular to the contact; the magma compressed the walls in the direction of the hammer head and the veinlets grew in the plane of possible extension fractures. Photo by Alden Loomis.