Granitic Gneiss Rock Deposit with Joints

This granitic gneiss deposit displays large scale banding. The darker grained, more ferro-magnesian minerals weather more rapidly than the lighter colored more quartzitic mineral bands. Thus the darker bands form the topographic lows, which in this case display a plunging fold structure.

The arrow at 3 in the thumbnail points to joints that are oriented perpendicular to the foliation direction of the gneiss. Home