| Answer | Crossword Clue |
|---|---|
| UTWO | Spy plane or rock band |
| UTWO | Spy plane or Bono's band, spelled out |
| slickenside | A polished and striated rock surface that results from friction along a fault or bedding plane |
| slickensides | A polished and striated rock surface that results from friction along a fault or bedding plane |
| nappe | large mass of rock thrust a considerable distance along a nearly horizontal fault plane or in an overturned anticlinal fold |
| nappes | large mass of rock thrust a considerable distance along a nearly horizontal fault plane or in an overturned anticlinal fold |
