Dextral Brittle-Ductile Shear Zone

Brittle-ductile shear zone marked by an en echelon quartz-filled veins in quartz-feldspar graywacke, Mullion, Cornwall, U.K. The aproximate boundaries of the shear zone are indicated by the yellow lines. The intersection of the vein tips and the shear zone boundary defines a "V" (red), which points in the opposite direction of the shear sense on the shear-zone boundary. The shear-sense on the shear zone is right-lateral. R&H photo.