The famous "multi-colored outcrop" in northern Scotland. Behind the green grass and a gray road, this unusual outcrop of rock consists of ~3 billion year old Lewisian gneiss (light gray) cut diagonally by 2.4 billion year old amphibolite Scourie dikes (black) cut diagonally by 1.8 billion year old granite pegmatite dikes (pink-red). The Lewisian gneiss in the upper right is un-dissected by dikes. The thin, evenly-spaced, parallel, vertical lines are man-made marks made by the drills used when cutting this outcrop for the road.
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Jerry D. Harris 🦕👣
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